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What is this called and where can I buy a replacement?
In the image, there is an object circled in blue on the anet a8 printer that I need to buy a replacement of, however, I can not find it online, please help.

This is the throat block for direct drive extrusion, Anet8 is a cheap clone of Prusa printers, so it's easy to find parts for Anet printers.
This is one extruder kit that may help your needs, 1 Unidades Impresora 3D makerbot MK8 Extrusora De extrusión de Aluminio Bloque de DIY Kit para Reprap i3. This is a link for Aliexpress - of course there are other dealers.

Note that "throat" is Chinglish for "heatbreak".

@TomvanderZanden That could be because the Chinese do not know whether to use heat break or heat brake. Neither do I.

This is part of filament drive. Anets do not sell it separately, only as a part of extruder assembly, but other manufacturers may make incompatible parts: of different size (not fitting into bracket), filament channel position, etc.

Like @ZuOverture said the name of this component is the filament drive. Most of the manufactures sell the whole extrusion device already assembled, to avoid mismatches between the components of the extrusion device. If your device is somehow damaged, and without possibilities to be used in the printer the easiest solution would be to buy a new extrusion device. If financially is unfeasible for you, you may have the option to generate the 3D model of this piece and share the file to someone who could print this component for you.

I don't think this is a printable component. It looks like it needs to be made of metal, because the heatbreak screws into it. Plastic would melt.

Can you check the material? For my 3D printer, most of the filament drive is made of ABS. The heating system on the extruder is made of Alu and brass. In the photo you have showed it looks like that is just a component to give support and stability, the heating system is below near to the extruder. I have a question for you, what is the problem with your component? You have said that you need a replacement , but did not explain why... Did you brake it during the assembling of your printer? Or did arrived to you already broken? What is the problem?

I agree with @TomvanderZanden. It needs to be made of metal since it is acting as a heat sink as part of the cold end.

Hello @Mick, could be made of metal yes. Anyway, Tom could easily check which material is made the component. And still, the important question is what happened with the original piece. If it is made of metal is difficult to damage, maybe is possible to reuse it. And most likely he will need to buy the whole extrusion device as a replacement for the piece. I am curios to know what has happened to this component. Cheers!


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What is the meaning of extruder's knocking sound?
I have a Prusa i3 printer with mk8 extruder. I am using PETG with (200-240/75-85) degrees recommended temp on it's box. but when I do printing i hear some knocking sound that means there is a problem in extrusion. last time I did increase my temp up to 270 degrees!! maybe this sound solved! but it damaged my extruder's screw's inner Teflon and I forced to change it!
Now I have a new nozzle and extruder's screw, but again I can hear this sound during the printing! I thought maybe it's because of very close distance between the nozzle and the bed, but when I increase the distance, the filament starts to warping!
My nozzle is new and it can't be for clogging. so I decreased the print speed from it's default 60mm(in Cura software) to 50, but didn't solve this sound. Also when I use pronterface and do extrusion manually, it works nice with 200 degrees! but I can hear the sound in 190 degrees. But when I do printing I hear the sound even in 200 degrees! Is this mean I must increase the temperature for printing? how much?
By knocking sound I mean the sound you can hear when you have a clogged nozzle and the extruder's stepper motor can't push the filament into it and rotates with knocking sound!

The extruder motor may be skipping steps because of insufficient current. Typically, the stepper driver will have a small potentiometer that lets you increase or decrease the current. Increasing the current will give the motor more torque/force, but also cause it (and the driver) to heat up more.

It sounds like your filament is not hot enough to be extruded, which will cause the stepper motor to 'skip' (and produce a knocking or clicking sound). 200°C sounds rather low for PETG, and I do not get good extrusion below 215°C. I normally print at 225°C, with the first layer at 235°C. I also print slower than I do for PLA -- 40mm/s and 30mm/s for the first layer.
Note that thermistors can be inaccurate, and may report temperatures several degrees lower or higher than are actually being achieved.

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FEA in 3d printed solids
I would like to get a pretty accurate method to do finite element analysis (FEA) on my 3d designs considering the infill. I use Autodesk Inventor to design parts but the FEA can only be applied to a solid body (100% infill). Does anyone know software that can convert a 3d design to another but considering the infill so I can use FEA more accurately?

You're essentially simulating a honeycomb. I don't know how inventor works, but I imagine that in order to do this, you'd need to create 2 parts. One for the walls and one for the infill.

Check out Hypermesh Optistruct, which lets you perform topology optimization to identify the optimal distribution of material within any matrix in order to satisfy desired performance criteria.
https://altairhyperworks.com/solution/Additive-Manufacturing
Similarly Scott Hollister's work describes the procedure to design a porous scaffold to meet conflicting requirements such as mechanical properties for strength and porosity % for material diffusion etc.
https://www.ncbi.nlm.nih.gov/pubmed/16003400

Rhino will let you create a custom lattice structure inside the solid object, this can in turn be used to create infill using grasshopper (an inbuilt scripting tool):

create a standard cell size and apply the lattice,
convert the whole thing to solid,
reimport into inventor

In Tymrak, B. M., M. Kreiger, and Joshua M. Pearce. "Mechanical properties of components fabricated with open-source 3-D printers under realistic environmental conditions." Materials & Design 58 (2014): 242-246., the authors suggest that one of the strongest factors influencing simple tensile strength of a 3D printed part was the ratio of its measured mass compared to its expected mass calculated by the slicer. Given that many printers under-extrude (especially when used with manufacturer's calibration settings) the accuracy of your model may be moot if your model isn't as solid as you'd expect it to be. The authors also suggest that the presence of fillers and pigments affected overall part strength.
The researchers at the not-for-profit Nia Technologies develop technologies for 3D-printed prostheses. They have some published research, but I'm not aware if it includes their FEA technique or tools. From an informal discussion with one of their staff, it seems that material variability and even environmental conditions while printing have measurable effects on final strength.

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Knocking/Clicking sound when Y-Carriage passas trough the middle of rods
Here is a video about 30MB, that shows my printer and it's sound during printing: https://drive.google.com/file/d/1wj5_Uwv4X8SoLaouxBi1FHFi4x4Uoegd/view?usp=drivesdk
I guess the reason of this sound is the bed. Because I couldn't level my bed with screws and upper=left and bottom-right corners of the bed were about 1.5mm lower than the opposite sides. So I added two nuts behind the springs of these two sides! I don't know really if it could help but know I can print almost good.

So i think the knocking sound is because of these nuts and my bed carriage is not 100% flat(although it seems flat by eyes). Or maybe my rods aren't parallel(although they seems parallel by simple ruler measurement).
By the way, I like to know does anyone experimented same problem? or can guess the real problem or suggest a way to solve it?
And IMPORTANT question: May this problem break my heated-bed? Or causes new problems in future?

I don't think the sound is coming from nuts and springs.
I can think of 3 possible sources.
Y axis rod bearings
Those four bearings that are mounted onto your bed frame may be binding through rough spots on the smooth rods. Usually printer kits don't give you the best quality stuff and those rods may not be perfectly the same diameter throughout its length or may be bent so slightly. Your best bet to test if this is the problem is to remove the belt from your bed and slide the bed back and forth and see if you can recreate the sound trying different speeds and pressure while doing so.
Y axis pulley/idler
I think it's probably this because I have heard a similar noise and this part has failed on me. Usually these are either a plastic pulley, two bearings, two bearings inserted into a plastic pulley, or one larger bearing inserted into a plastic pulley. If your printer uses a bearing here, I recommend taking that part off and inspecting that bearing. I've had mine destroyed and the little balls went everywhere. You can test this by just trying to hear for it. Turn off the printer motors and move the bed manually, see if it sounds like it is coming from the idler.
Nozzle hitting print
I doubt this but sometimes when prints are over extruded or curl up, the nozzle hits the print as it passes over so maybe your hearing individual collisions clicking. Again I really doubt this.

Will this break your heated bed? Probably not. Will it cause problems in the future? If it is a fault with the bearings, most likely they will fail eventually but nothing else should get damaged in the process. But no worries, parts are cheap and readily available online or even at some hardware stores.

Note : My mechanic taught me this when trying to figure out which bearing was making noise in a car. Take a long screw driver, preferably with a wooden handle, and place the tip on the part you think is making noise and place the handle to your ear. Usually this amplifies the noise when your making contact with the faulty part. Using this I was able to figure out which bearing was squeaking among the half dozen points where the belt would spin. Not sure how well this works for a printer and be careful not to have the mechanical moving parts(such as your printer bed) hit the screwdriver into your face.


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Why some corners aren't sticked well?
Is this a leveling problem? or it's because the bed temperature isn't equal in everywhere?
If it's because of leveling, it means the distance between nozzle and bed in this not-sticked corners are lot and should be decrease?
EDIT: material is ABS, and it's recommended temp is 190-230/80-100. But I use Cura high quality ABS default settings with 225/80. (But I had this problem with PLA with 190/60 degrees too)

EDIT2: I have a cooling fan for my Arduino/ramps board. But there was a wire between it's blades and it didn't work. today I saw it and tried to fix but it's plastic duct broke. So I tried to put it by hand as how it's air can cool both the Electronics boars and the bed(you can see my fan in one of the pics in left side). And I got a nice printing results for the same part printing:

So the cooling fan for printing part is very important to stick print to bed and I will print a duct for extra fan very soon!

What material please? I had PLA unstick because my heat bed was too warm. 60°C was too much, 50°C first layer then 30°C works perfectly well (for me).

@Valmond: I edited my question.

You can clearly print but there are also some problems it seems.
To see if you're about okay when it comes to leveling, I recommend to activate the 'skirt' in your slicer soft. Slic3r has it and I think most others too, it just makes the printer do a big one-layer all-around 'perimeter' around what is going to be printed before starting. You'll see quickly if there is not enough or too much space between the bed and the nozzle. You might catch other problems too (I love it because when the hotend drips a bit when leveling it get's smeared out far away from where the print is going to happen).
Your print looks like it is not optimal (overextrusion? no print-cooling? ...) so start with slowing down, first layer 20-25mm/s (Look at it when it's printed, it's very telling!). Then for the following ones, don't go over 40-50mm/s for starters.
Last but not least, you are printing ABS (but you said you had the problem with PLA too, hence my post), I have never printed ABS but for what I have read, you'll need a heatbed and a heated chamber(enclosed printer) to not have this kind of problems.
But for PLA especially; If you have a heat bed, don't put on too much heat when printing, I went from 60°C to 50°C, first layer, 30° then, and my prints now stick like they are melded onto my plate instead of skidding around.

For ABS, I use kapton tape, 90 degrees for the bed. You can also try acetone/ABS mixture (can be very thin). If you haven't got acetone, clean or new tape so there is no grease on it.
You can also try a higher nozzle temp for the first layer, sometimes that helps.
You can also try lowerimg the nozzle slightly, but it doesn't look bad. Increase flow rate to 110% probably wont do any harm - basically focus on the details before trying to print complicated parts.


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Printing starts well but then it breaks down, Anet A8
I'm printing a cylindrical piece but at any moment it breaks down. I tried it two times, both have break down in different place. I'm using a 1.75 mm PLA filament in my Anet A8. I'm using Cura 2.6.2 to export to a .gcode file.
This is the original model:

And this is the result:

Here is the G-code file.

What temperature are you using? Seems the temp is way to high, so either cool better or lower the print temp (if that's possible).

The first thought that pops into my mind is insufficient cooling. Consider to either slow down the nozzle speed or to construct a toss-away model nearby. I prefer the toss-away or duplicate model method. It allows the material printed on the first column to cool more effectively while the material on the second column is being deposited.
If the problem persists, add a third column or slow the print speed about 10 mm / second

I have the speed in 30mm/second, is it too fast?

@legomolina You can't solve this problem just by reducing the speed. Keep in mind the nozzle radiates heat, so if it always stays within the same, small, area, that area will never get a chance to cool down. You should really consider printing two copies of this model at once, so the extruder will go back and forth between printing the copies and give the layers some time to cool down.

Ok, ok. I'll give it a try

@legomolina The stock A8 fan is useless. Set fan to 100%, and print this (if you can) https://www.thingiverse.com/thing:2121279

@tom, I have never reduced speed, only used the additional column method. Perhaps that qualifier means I should have left out that option. Thanks for the clarification.

The answer by fred_dot_u is fine for small prints with relative low cost or batch producing, where a single part is needed several times. But if you print something big or unique it's not cost effective. Slowing down the complete print is also not very time efficient.
In Cura there an option called Mininum layer time, which addresses this problem:
Cooling -> Minimum Layer Time / Minimum Speed

This means that it will only slow down when the print distance for a particular layer is short. Giving the material some extra time to harden. Other layers will be printed at normal speed. Increased print time will be limited this way.
For your situation I would advise you to increase the part cooling, if possible, in conjunction with configuring the Minimum Layer Time option mentioned above.

Hi Shwans and welcome to Stack Exchange! :-) It is better to reference the answer to which you refer by either the URL, as I have done, or the poster's name. Saying answer one will be of no use when/if the voting changes the order.

A side note: this feature was introduced in CURA 2.4, June 2017.

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How do you assure that you print layers that bond correctly?
I'm fairly new to 3D printing but I'm getting the steam up and I chug out pieces without much hassle. One thing though is that I have the impression that sometimes, parts are easily broken, and I suspect bad adhesion between layers.
I'm printing eSun PLA at 208 °C (212 °C first layer), bed at 50 °C first layer then 30 °C.
When I print the Benchy boat, it feels extremely sturdy (even the small chimney is unbreakable by hand), but if I make, say, a 50 mm diameter cylinder with 4 mm wall thickness, It breaks fairly easy along some layer. I don't see any specific error, it "looks" okay.
So my question is:
How do you assure that you print layers that bond enough?
[Edit] I already know that might actually cause bad bonding (low heat, underextrusion, ...) but I'm looking for a way to see when it happens.
Here is an image from when I stopped mid print (you can see the little ooze string just at the start at the crack) for checking dimensions. The next layer didn't bond well because, I guess, the already printed part had cooled down when I un-paused the print (say 1 minute later) or maybe the z-axis went off a bit when I touched the build plate.

Is the only way of knowing layers bonded correctly, to try to break the part apart?

You should get good adhesion at those temperatures. What speeds and layer height are you using. Also, what is the nozzle diameter (if not 0.4mm)?

@Mick 0.4nozzle and 0.3mm layers, low speeds (50-60mm/s max, around half for any tricky details).

Although it is possible to print at 75% of the nozzle width, I would suggest that you try a 0.2mm layer height.

@Mick Will try!

I think the reason why the large cylinder is breaking much easier than the smokestack would is because of leverage. If you print the same cylinder at a much smaller scale it might be more difficult to break it. Think of taking a wooden stick, if you try to snap it by holding both hands near the center, it would be difficult but if you push on the very ends, the leverage will make it easier to snap. I have the tug boat on my desk right now and I was unable to snap it, instead I broke the cabin section just right above the steering wheel.
Now to answer your question. One of the faults in larger prints having weak layer adhesion could be a number of things. I think a common fault is under extrusion. If the nozzle has a high enough gap from the previous layer and it extrudes just enough filament to touch the layer but not necessarily push it snug, it could be a weak bond. This is like tape, usually when you want to make sure it will stay stuck, you press hard and rub it in. So I imagine filament shouldn't loosely flow onto layers but instead be pressed hard against the previous layers. Visually this is hard to judge but I noticed getting my first layer very close to the print bed makes every other layer stick very stronger on the previous one. You get a small skirt on the first layer but it does tend to give me a stronger bond between layers. You can easily slice off the skirt with a blade. Increasing the extrusion multiplier could give the same affect without needing to adjust bed height/leveling, but this can end up giving you some nasty walls.
Another thing I recommend is to check your Z-axis. This is difficult to measure and best to find out by print quality on tall structures. On my first printer I had the issue where my threaded Z-rods would bind and cause one of the two rods to get a slight bit ahead. This caused a layer split focused on the side opposite of the faulty rod. This made many prints very prone to breaking at that point. I had to rebuild my Z-axis assembly to correct this.
Print temperature can help, try raising it up by 5 to see if this improves the bonding.
Lastly, try another filament. Filament tends to go bad due to moisture exposure, that is why usually you receive it airtight with a small bag of silica to absorb moisture. If I use filament which has been sitting out for months, just squeezing my part separates the layers in almost a slinky kind of way.

Thank you for the lengthy and well informed post, but I still don't know How I'll assess that the layers actually stick well together, without destructive testing...

@Valmond Oh sorry I completely missed the question. I took it as "What can I do to increase layer bonding". To answer your question, You can't unless you measure the amount of force needed to destroy the print or by visually inspecting it. By the picture you provided I see many small gaps every 5-15 layers and I can assess that those are your weak points. Your best bet is to fine tune your printer and/or settings and test the parts destruction. If your confident in their strength, using PETG and other stronger filaments should give you a clear head on how strong your prints will come out.

I think it's not possible and just overextruding (a little bit), squash that first layer correctly and bomp the temp are the things to actually do to make the best out of it. My PLA is now unbreakable ^^

I bought a used Monoprice 15710 yesterday. First thing out I went for, the little whistle. The layers would fall apart while printing. I could see by everything you wrote I was OK, but maybe for the head temperature. I raised it from 200 to 220. The whistle came out strong and about as perfect as it gets, and it works! Thanks.

No matter what you do, the adhesion between layers will never be as strong as the adhesion in the direction of layer application.  It's analogous to a wooden baseball bat (for those old enough to remember them :-) ).  If you apply force perpendicular to the "grain," i.e. growth layers, it's strong.  If you apply force along the grain, it'll snap pretty easily.
Now, if you print a cylinder vertically, it snaps between layers.  If you print it horizontally, the layers run along the cylinder axis and it won't break. That's of course a much more difficult print with extrusion systems, and cosmetically less desirable as well.

Yes but the Benchy boats smoke stack is literally unbreakable by hand, and it's printed as a cylinder too. And it's smaller.
Love woodworking (and remember old wooden bats, both the flat and the round ones :-) and orientation strength works for paper too, much easier to rip in one way than the other.

@Valmond  Are you sure the smokestack is printed exactly vertically?  Did you check the wall thickness, infill, etc?

@Valmond Are you using a part-cooling fan? If so, try turning it off.

@CarlWitthoft I think so, and I use the same parameters for all my prints.

@Mick Not yet a cooling fan on my build :-)

(Note: I realize this question is old, but I came across it looking for information on related topics and it didn't seem to have any sufficiently good answers yet.)
To me, this looks exactly like what I'd expect printing with layers almost as thick as the nozzle diameter and insufficient hotend temperature or excessive speed. I've had problems like this at sizes 0.3 to 1/3 mm using an 0.4 mm nozzle even at my usual PLA temperature of 210, and can imagine it would be much worse at lower temperatures. If you didn't see the problem on benchy with a smaller cylinder, it's probably either because acceleration limits (which will be dominant on small details) prevented reaching high speeds, or (less likely in my opinion) because the deposited material had not had as much time to cool before the next layer was reached.
In order for layers to bond the newly deposited material needs to be pressed against the material already present, while melted, with sufficient heat transferred into the already-deposited material to make it amenable to bonding (naively I would guess this means it needs to reach around the glass transition temp, but that may be wrong). With layer thickness near the nozzle diameter, the nozzle will be putting less pressure on the existing material, making this harder. Also, if there has been underextrusion anywhere in the supporting wall below, the already-deposited material can simply compress downward into the gaps when new material is extruded against it, rather than them getting pressed together.
For 0.3 mm layers, I'd go with the highest temperature the filament manufacturer rates it for, or even slightly higher if you have reason to believe the material is okay at higher temperatures. Some people say lowering the fan speed or turning it off is an option, but I've had really bad results with precision and/or stringing whenever I try that.
Significantly lowering the print speed is also an option. That will greatly reduce the chance of underextrusion, and results in more heat transfer from the nozzle into already-deposited material. However lowering the speed generally defeats the purpose of 0.3 mm layers; you could instead just drop down to 0.25 mm or 0.2 mm and get much better quality at the same total print time.

Thanks! I actually "solved" the issue (not the issue knowing if there is layer adhesion, but it now sticks well) by upping the temp to 220°. Slight over extrusion also helps but it messes with the dimensions of the items so I'm 'sticking' with he high temp fix.

@Valmond: Thanks for replying. Nice to know my suggestions roughly matched what worked for you.

@Valmond upvotes for terrible puns!

From my experience the most profound difference is in the material. Especially with eSun PLA that I have used over 10 spools I have found huge inconsistencies. In one spool the printing adhesion was fine on other spools it was very very bad. My first advise is try another branded filament, I would recomend Colorfabb, Polymaker and Formfutura for PLAs. Secondly if you want to use the eSUN try higher temperatures, go above 210 or even 220.

Thanks, I did exactly that (and I use eSun), starting off at 214 then 212 works great. I also extrude slightly more and the extruder was a 0.05mm to high...


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What is PLA+? How is it different from PLA?
Question
What is PLA+? How is it different than PLA?  I'm looking for science, composition, formula, safety concerns (or lack thereof), etc.
Background
I picked up a roll of PLA+ at Microcenter (their in-house Inland brand) because it was on clearance.  I didn't even notice the "+" until I decided to try that color, and then I noticed it on the sticker.  It prints well, feels like ABS, smells like PLA when printing, and I can use PLA temps on my printer.  It sands better than PLA, and if I I hadn't noticed the PLA+ sticker, and the smell, I would think it was ABS.  It will break its line into my printer like PLA does; ABS doesn't break if left alone.  However, PLA+ lasts longer than regular PLA before breaking.
Getting info from the Internet
Aside from a few discussions on reddit (review, commercial introduction), I can't find anything about it.
Getting info from the Manufacturer
I went back to Microcenter and the guy that was there working the 3d printing section did not know what I was talking about.
I went to Microcenter another time and the guy in the filament area said that all of their PLA filament was now PLA+, and that the + meant it was to be used at a higher temperature.  The boxes are labeled with 205 - 225°C.  It seems that all the inland brand PLA I have is PLA+, save for the first roll I bought.  It does not have any kind of temperature markings on it.
Flash forward 1.5+ years from the original question
This question got some recent attention, so I looked to find the answer again.  I found this article, which is a hot pile of !usefulness, giving no data, lots of opinion, and probably some direct insights from someone's marketing department.
These guys say it's good stuff, but nothing about the chemical or compositional difference between the two.  When I find people talking about the difference (like on reddit), those are the details usually mentioned, which are vague, anecdotal, and opinionated, and could be clever marketing (could be, not guaranteed to be).  One man's shiny is another man's matte for example.
Monoprice confirmed what I already did by reading the label and printing with it, but does mention TPU, which might be Thermoplastic polyurethane.  No quantity or proportion or anything, and since they're the only manufacturer/reseller to officially say this, I consider it unconfirmed. One of the answers below says that PLA+ probably includes TPU or something like it, but that's conjecture or opinion by their own admission.

PLA+ is a variation of PLA that has added material in order to make
  the filament less brittle, have a smoother surface finish, and less
  likely to absorb moisture. Typically, TPU is added into the filament
  in order to achieve this property. PLA+ will have the feel and
  functionality of ABS without the smell. If you didn’t know better, you
  would think it was ABS. We suggest printing with PLA+ at 205 to 210
  degrees Celsius and with a bed temperature of 45 degrees Celsius. PLA+
  responds very well to blue painter’s tape and a glue stick to hold
  properly and not peel up when printing.

These people also ask what it is, but they're doing science about it circa 2014 to try to figure it out.
I'm not sure what to think of this manufacturer/seller's description.  It sounds like they are implying that PLA has a branding problem, so they added a plus to it for a new formula to fix their branding.

PLA Plus is an enhanced version of our PLA that's less brittle and
  more durable. ‘Enhanced’ PLAs have a bad reputation, some are no
  better than PLA, some perform worse in some conditions. We’ve taken a
  different approach: our ‘regular’ PLA is regarded as the strongest
  pure PLA in the industry, it’s hard to improve on the best. But
  sometimes you need something a little more durable. Enter our
  specially formulated PLA Plus. Prints like PLA, but with better
  durability. Its available with their brighter color options!

Final thoughts
I find a lot of articles/posts talking about "eSun PLA+" specifically.  I'm starting to think that this might be the OEM and that other companies are selling it with their own branding, but that all PLA+ comes from the same place.  I found their product page, and it says this, which mentions nothing about the formula:

Characteristics：

extracted and purified from corn grain;
high rigidity, good glossiness and transparency;
suitable for printing larger models;
toughness is 2 times more than the PLA on the market;
no wiredrawing problems, the surface of the printouts will be smoother and more delicate;
no cracking problem.

I don't think there is any standard formulation. Different manufacturers add their own modifiers (and usually stay tight-lipped about what they are).

Disclaimer: I am not affiliated with any linked brand or company, I just link to them for reference of the suggested print settings.
What is PLA?
PLA is, by its definition PolyLacticAcid, a polymer of entwined lactic acids. It is commonly made from fermenting starch - not via Type I (alcohol) but Type II (lactic acid) fermentationuser77232, Wikipedia. Chemically it looks like this:

It's relevant physical data for the pure material are a density of 1.210–1.430 g·cm−3 and a melting point of 150 to 160 °C.Wikipedia.
Usually, PLA sold under just the name PLA contains, besides PLA, additives to change the color from transparent to whatever color one is printing at. This can change the standard printing temperature depending on the amount, size and shape of the pigments embedded (see below).
Common Printing temperatures are listed by the manufacturers in the range of 185 to 210 °C. The color can have an influence on the printing temperature, especially for the difference between transparent and opaque filaments. While a heated bed is not strictly necessary, the bed temperature is usually quoted with 60 °C.
I myself print most PLA filaments at 200 °C and 60 °C bed, but for noncolored transparent filament, I had better results using 190 °C.
Note that not all PLA is just PLA! It is very likely that some PLA brands contain fillers and additives from the house without claiming to be a +-filament, indeed, additives precede the idea of PLA+, as the case with Tiertime PP3DP filaments will show.
The special Tiertime mixture
Since back in 2012 or earlier, ABS made by Tiertime includes some unknown compound (possibly PC) that alters the best-result print temperature from the "normal" 220 - 240 °C to the much higher but narrower 260 - 270 °C band. Why this is done is a mystery among 3d-printing enthusiasts, but it might be either to get rid of any color-dependency of the print results or to make it harder to use generic ABS. Fact is, that this temperature was matching what was set as the (then unchangeable) standard temperature in the Up 1.1.7 software of that time.Angus aka MakersMuse & Tiertime Forums. The higher temperature hasn't changed over the yearsTiertime ABS. Indeed, the Tiertime PLA introduced in March 2014Tiertime is also quoted to print at higher temperatures than generic PLA, and had similarly a higher default temperature in the then updated UP-spftwareTiertime Forums, though I found listings from 200here & here to 215 °Chere under Technische Daten.
The modern UP-Studio software allows setting the temperature freelyAngus aka MakersMuse.
What is PLA+?
Now, what differs PLA from PLA+? Well, PLA+ is a modified PLA, which means that it has additives in it to alter its properties. What exactly is added depends extremely on the manufacturer, and no two PLA+ are the same.all3dp.
What is the difference?
PLA+ has - but for a few degrees - the same printing temperature as standard PLA. In fact, the printing temperature difference between standard PLA from different brands is often larger than the difference between PLA and PLA+.
All3dp claims, that most PLA+ would have a better surface finish than the PLA from the same brand. Because of the additives, they also usually print best at elevated temperature compared to PLA. Among various manufacturers, I saw 210–240 °CKodak PLA+, 190-220 °CSUNLU PLA+ and 190-210 °CeSun PLA+.
However, there is no uniformity in other effects on the filament. Some filaments would have less moisture absorption, a different stiffness or compressibility while others might have a higher tensile strength and feature an extremely glossy surface.
Most commonly, the claimed benefits lie in the fields of the filament's strength, surface texture and glossiness, the printability of overhangs.
Conclusion
PLA+ is not one product per se but a family of modified PLA. While you can print PLA+ with the same settings as normal PLA, the resulting benefits between different brands are much more diverse than with normal PLA.

Changing between different brands of similar quality normal PLA has usually little to no effect on the print's general properties.
Changing between different brands of similar quality PLA+ can alter the print's properties immensely

Because of the fact that no two brands of PLA+ are the same (and the manufacturers are silent on what additives they use to change the properties), one should not rely on the same effects when switching between brands.

"It is commonly made from fermented starch." - specifically type II, lactic acid fermentation. Not type I - alcoholic fermentation :)

There’s no huge difference between both. The printing settings like temperature and printing speed are practically the same. But the PLA+ have a much better surface quality and it’s slightly more bright than normal PLA. Another difference is that the PLA+ it's more effective in bridges than PLA.
If you want to the comparison between PLA and PLA+ go right here, PLA vs PLA+ (short review). This post is an awesome experiment with both materials.

That's the first link I link to in my question.

Some of these questions could be answered by asking manufacturers for MSDS (Material Safety Data Sheets), aka. SDS (Safety Data Sheets).
Under EU laws in place since 2008 any substance shipped into the EEA (European Economic Area) in quantities of more than 1 tonne/year, whose composition contains more than 0.1% by weight of a compound identified in the Article 57 database, must provide an MSDS on request that includes a breakdown of its content.
If you look at the SDS for eSUN's PLA+, for example you see:
╔═══════════════════╦═══════════╦═══════════╦═════════════╗
║ Ingredient Name   ║   CAS No. ║    EC No. ║ Content (%) ║
╠═══════════════════╬═══════════╬═══════════╬═════════════╣
║ Polylactide resin ║ 9051-89-2 ║ 618-575-7 ║          98 ║
║ Calcium carbonate ║  471-34-1 ║ 207-439-9 ║           2 ║
╚═══════════════════╩═══════════╩═══════════╩═════════════╝

Hi, welcome to 3DPrinting.SE! If you look up the MSDS for PLA you will see that the content base material is also > 98 % Polyactide resin. The rest is probably coloring die. What is the difference?

Rather than guessing ask for an MSDS. There's probably no reasonable difference at all, and that's kind of the point. It's like paying a car dealership 2600 dollars for a replacement windscreen or paying Windscreens O'Brien 397 dollars - there's no difference between the two, the car dealership is just the charging more for no good technical reason.

That seems like a good lead.  But then I suspect a lot of retailers won't know what an MSDS is, and Microcenter might tell me to talk to the Microsoft Office guy.

PLA+, depending on the brand, is probably a mixture of other plastics (things like TPU1) to help improve upon the weaknesses of regular PLA like brittleness and moisture absorbing. Or they simply used a higher quality PLA blend to create the filament.
I do not have a specific source except from collaborating with different materials experts such as Essentium Materials. TPU is a flexible plastic that can have different "hardness" levels.

1 Thermoplastic Polyurethane. It's a flexible thermoplastic.

PLA+ is a marketing term. Where PLA and ABS have specific chemical meanings (more or less... manufacturers already will have different additives or processes), the only real requirement for PLA+ is using some unknown quantity of PLA as a base.
Look at coffee beans as an example: we have Arabica vs Robusta. Arabica is usually considered better, for some definition of "better". (BTW: Starbucks serves cheaper Robusta). The relevant thing here is in many places you only need 10% Arabica content to label and market a coffee as Arabica coffee. The rest of the product could be... well, anything the maker wants to include.
PLA+ is similar. There's no real definitive meaning to it, beyond some measure of original PLA content and the hope you'll believe it's "better", and therefore maybe pay a little more.
The good news is, usually PLA+ really is better... at least so far. But as more people start viewing it as a real step up from regular PLA, it's likely we'll also start to see some shady business people pass off inferior product at PLA+. It's likely this is already happening.
Moral of the story: read the label carefully. And unlike coffee, which is a food and therefore better regulated, filaments have hardly any rules about labeling; there may not be a label to read at all, so be extra careful what you buy.

Brands are brand names like Kleenex, Scotch Tape, and Duck Tape, not tissue paper, clear tap, or duct tape.  I think I get what you mean with the analogy, but that isn't a brand.  If you're saying that PLA+ has some other material besides PLA in it, where did you find that information?

I know this is an old question, but CNC Kitchen just recently did a review of PLA+ and the mechanical properties of one brand, and found it far weaker than plain PLA, but with failure modes that might be mord graceful/preferable for some applications. In short, it stretched and tore rather than snapping.

Adding this as a new answer since it doesn't seem to be covered in existing ones:
Despite "PLA+" being a marketing term without a specific definition, I've found that many (most?) filament vendors don't seem to be doing their own secret-sauce blending to make it, and most premium filament vendors who do document the source polymers they use are using roughly the same thing - most often one of the Natureworks Ingeo 3D series of polymers, obtained in pellet source form, often 3D850 or 3D870. As such, if you can verify that this is what you filament marketed as "PLA+" is made from (or just search out one that's well-documented) you can use the data sheets for the polymer to find out more about how it's formulated.


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Where is the "slice" button in Cura?
I'm relatively new to Cura, having just installed it a few weeks ago.  I have 3.0.3 and I'm running on Windows 7 64 bit.  I noticed the auto slicing setting while poking around the settings.  Auto slice almost always works.
A couple times now, Cura won't auto slice. I can't seem to find the slice button.  How do I manually slice?  I found an article on how to disable auto slicing, but it doesn't show how to manually slice.
Where the button "save to file" is is greyed out and just says "Print with Octoprint".
Closing Cura and re-opening it will fix the issue.

Probably an example of this bug. https://github.com/Ultimaker/Cura/issues/2693 Can you reliably reproduce it?

Maybe do a reinstall? I dont know if you messed with the settings?

If auto-slicing is disabled, the button in the bottom-right corner of the window toggles between "Prepare" and "Save to File" depending on whether the model needs to be re-sliced or not. While slicing is in progress, it changes to "Cancel".
If auto-slicing is enabled, the button always reads "Save to File", and is greyed-out when slicing is being performed (it does not change to "Cancel").

Does that button show up when auto slicing is enabled?

Yes, Answer edited.


text:
I am looking for STL files of my Prusa i3 printer?
This is my 3D-printer, and I am looking for it's .stl parts to print. Also I don't know which kind of Prusa is it?

There are a thousand-and-one Prusa i3 variations. Without some more information, it is impossible to identify this specific part.

@TomvanderZanden: The problem is here that I don't know what name do my model have?

So, add a photo of your printer so that we can identify it.

@MickL I added some photos

I would try Googling your specific make of the i3. For example if you have a Geeetech Prusa i3. I would type in Google "Geeetech prusa i3 stl parts" and I'm sure you should fine plenty of things.
If that is unsuccessfull. I guess try this one. It looks similar but it lacks that hole on the bottom middle to the right of the motor holes. So if its not important, I would look at this. https://www.thingiverse.com/thing:1103976. Might be a good idea to replace the entire X axis system with a new printed one to make sure it all fits and works.
@Tom van der Zanden is correct that without your specific version it is impossible to find the same part since small variations such as the distance between the two X axis smooth rods may differ between parts. While it is almost standard for the i3 design, you will find minor changes between variations.
I would also try scrolling through here. https://www.thingiverse.com/groups/prusa-i3/things


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Oven/Food safe Filament?
I just backed a 3d printer on kickstarter, called "Mooz", and I was wondering about some of the possible applications of it. I realized it would be cool/helpful to be make cookie models, and bake cookies to that shape. The cookies can be baked as low as around 250 °F, So is there any food-safe and heat resistant filament that can withstand those temperatures? (I know many filaments are printed above those temps anyways, but in my case I don't want them to even warp.) Google has failed me on this one, so I hope someone here can answer it for me!
-Thanks in advance :)
P.S. My 3d printer will have a heated bed, so it can print more types of filaments. The highest bed temp is 100 °C, and the highest hot end temp is 250 °C. I don't really mind using some sealant, but I'd rather not use something toxic like ABS.
P.P.S I'm a newbie to this stuff, so I apologize in advance if I asked a really stupid question.

You could possibly use printing, lost-wax casting, and silicone to make the mold. https://en.wikipedia.org/wiki/Lost-wax_casting

Don't try to bake cookies inside a plastic mold; the plastic will smoke even if not melt. If you need to bake cookies use a cookie cutter made of plastic (your own design or copy) obviously printed on your new printer then bake normally. here is a link from thingeverse to get a cookie cutter .stl file
:) enjoy cutting cookies these holidays
Here is another link from hacks from one person is making the same to show his idea.

I was thinking of more about PC, which has a http://https://en.wikipedia.org/wiki/Polycarbonate glass transition temperature of around 147 °C according to Wikipedia. The oven would be around 50 °F cooler than that temp, would it still smolder?

Sorry- I forgot to add that I could technically bake the cookies at as low as 250 °F, so would there be a filament for that temperature?

@Rafael No my friend, never try to use plastics for molding cookies or cook. Plastics are only used for storage and can be harmful if the plastic gets hot for long periods due chemicals (odor or smoke). Plastics becomes soft at lower temperatures of melting, so in this lapse the plastics release the odor that can be mixed with your food contaminating every thing. The kind of plastics for molding is silicon with food grade (clean of toxines).

There's obviously some 'safe' range of temperatures for 3d filaments. Baking aside, what's a general safest, hottest temperature for a plastic filament? The bed temp?

@Rafael Oh, this is another kind of question and I have the answer for each plastic. Please open that as new question.

I opened a new question here: https://3dprinting.stackexchange.com/questions/5013/what-are-the-safest-temperatures-to-heat-different-filaments-to


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What type of fire alarm/smoke alarm should my printer have?
I know you should, like an infant, never leave your printer without surveillance.
But sometimes we all do, trusting our double thermistors and heat runaway configurations. But electronics fry and who says there is no danger even after the print job has finished and it's cooling down, still hooked up?
I have searched but smoke/fire detectors come in a wide range of varieties:
They can be battery powered or hardwired, they detect different things: carbon monoxide, heat, smoke..., they thus also have different detectors like photoelectric sensors, ionization sensors or both. We also print with different materials...
So what's the best safeguard for my 2 year old (CoreXY ^^)?

The best safeguard is to use high-quality components, and to separately fuse every item that is connected to the power supply.

Since some prints can take literally days, I would use a combination of techniques if you're worried about a fire.  According to The Internets, firefighters are willing to inspect your stuff to see if they pose fire hazards.  You could ask your local firefighters what they think of your risk with yoru 3D printer.
Keep your workplace free of dangers
Don't keep flammables, explosives, or similar stuff near your printer.  If it does catch fire, these kinds of things will make it worse.  There are plenty of valid 3D printer supplies that fall in this category: alcohol, alcohol pads, acetone, acetone pads, various glues, various cleaners, hairspray, etc.
Periodically inspect the high amperage parts of the system
Inspect crimps, but splices, solder joints, relays, etc for burn marks, loose connections, or other problems.  Solve the problems before they catch fire.
Alarm
One or more smoke alarms should detect a fire.  However, they may give false positives for ABS, because ABS gives off that burning plastic smell.  I would experiment with the super-cheap ones and one or two more expensive models to see what kinds of false positives you get.  You'll probably want to put at least one of them directly above the printer.  If your printer is enclosed, put a sensor in the enclosed area.
I think smoke alarms should be sufficient, but I'm not an expert (or even hobbyist) on fire alarms.  I have not come across any information that states Carbon Monoxide or Radon are a worries with 3D printers.  Area-affect heat sensors may give many false alarms because of how hot printer stuff gets.  However, you could use contact heat sensors for parts that should not get too hot and monitor them with a microcontroller or Raspberry Pi.  Reading this article, it seems you may want some ionization sensors for the printer, and not photoelectric.  My WAG (link) is that the plastic (or electronics) would smolder long before catching fire, so you want sensors that would detect the smoldering.
Camera
OctoPrint/OctoPi make it easy to use a webcam to monitor your printer.  However, if your printer is on fire and you're remote, it may or may not be able to shut the printer down.  Even if successful, you still have a fire to deal with.
Fire extinguisher
You should have a fire extinguisher available to someone to put out your printer should it catch fire.  Printers will need at least an extuingsher of Class C rating, and since we're working with plastics, you probably want Class B as well.  Most of the fire extinguishers you can find in consumer stores are going to be ABC rated, and powder based.  The powder will make a mess and wreak havoc on electronics.  CO2 or Halon will not themselves damage the electronics, but are substantially more expensive than their powder based brethren.  For example, I get 5lb Fire Extinguishers for ~$30 at Costco, but an equivalent in CO2 would be several hundred.
Automatic suppression system
As a maker, you could build a reactionary fire suppression system.  I imagine it would be cost prohibitive to hire someone to do it for you.  Basically, you would use the alarms or special sensors to activate one or more fire extinguishers.  You should over-engineer this so that your fire suppression system completely overwhelms any fire that occurs.  According to The Internets, firefighters are willing to inspect your stuff to see if they pose fire hazards.  You could ask your local firefighters what they think of your risk and suppression system.
Firefighting Robot
You could build a robot to detect fires about put them out, as sort of an advanced automatic suppression system.  Something like Tony Stark's robot, or something emulating what is actually in service (US Navy (CNN), Australia tracked firefighter).

According to http://www.fireservice.co.uk/safety/smoke-alarms/ you have these two choices:

Ionisation: These are the cheapest and cost very little to purchase.
  They are very sensitive to small particles of smoke produced by fast
  flaming fires, such as paper and wood, and will detect this type of
  fire before the smoke gets too thick. They are marginally less
  sensitive to slow burning and smouldering fires which give off larger
  quantities of smoke before flaming occurs. They can also be too
  over-sensitive near kitchens.
Optical: These are more expensive but more effective at detecting
  larger particles of smoke produced by slow-burning fires, such as
  smouldering foam-filled upholstery and overheated PVC wiring. They are
  marginally less sensitive to fast flaming fires. Optical alarms can be
  installed near (not in) kitchens, as they are less likely than
  ionisation alarms to go off when toast is burned.

Although 'overheated PVC' might tend to point to the optical sensor being best, any fault on a printer is likely to be quite different to a domestic installation fault (I think you're less likely to detect the early warning from a damaged connector since the fault will be physically small).
I have an ionisation sensor next to/above the printer, and the only time I had a false-alarm was when I temporarily placed it on the desk.


text:
Z Steppers just hum, vibrate and don't move at all
As I said in the title there is some issue with my z axis steppers. They will make a humming sound and vibrate a little but won't actually spin. I'm fairly sure this is an issue with the firmware (but I might be totally wrong) since they turn when the wires are switched with the ones for the Y axis and swapping the driver board for a spare had no impact on them. Any help would be appreciated. I am using RAMPs 1.4 and marlin firmware.

It sounds like a bad connection on one of the wires, or switched wires. Try substituting a different cable.

try to switch 2 the wires; don't forget to turn off your shield.

sounds like stepper current issue

Try connecting Y-motor to your Z ports. If Y-motor will behave like Z-motors, then there's problem with your Z ports, be it hardware or software. I'm not a RAMPS user, but have heard that there is voltage regulator for every motor port. Sounds like your motors may be underpowered.

By "voltage regulator" you probably meant to refer to the potentiometer that lets you adjust the current limit.

@TomvanderZanden, could have been any. But even better this way, potentiometer is more newbie-friendly than programmable DC regulator of some sort.

Let's tick off the factors you have already checked for.
It isn't the driver board, because the Z driver board drives the Y motors.  It could be the Z motor itself (or the cable), which you could test by plugging the Z motor into the Y driver board.  If only one of the two motor coils were being energized, it would cause vibration but generate no motion.
@ZuOverture suggests it could be the drive current setting on the motor driver board.  Possible, especially if the Z motor requires more current.
It is also possible that the output pin from the Arduino Mega board may be bad, or not connecting well.
To investigate, find the step and direction inputs to the stepper driver board.  Use a voltmeter, logic probe, or oscilloscope to verify the signal levels.  If the signals don't jiggle when moving the motor, then follow the wires and check at each point along the way.
You could also plug in a replacement Arduino, which you have programmed with the firmware, and check if that works.
If the Arduino pin is bad, you can keep it in your junk box for future projects.
Looking at the firmware angle, one would check the speed and acceleration settings for the Z axis.  When in doubt, try slower speed and lower acceleration.  Z-axis performance doesn't make much difference in the printing speed.

Hello it's seems to be the voltage regutaltor on the steppers drivers for the nema motors. Check to adjust the voltage with a multimeter connecting the red pin from the multimeter on the voltage regulator on the driver and the black pin on the GND pin on the ramps 12v connector.
Also make sure that you have connected the jumpers to setup the microstep resolution:
Full step,Half step,Quarter step,Eighth step,Sixteenth step
Best regards.
Rodrigo


text:
ANet A8 Pre-Heat PLA Issue
When I go to Quick Settings/Pre-heat PLA, the computer dies the LCD screen goes blank the power supply makes weird noises and then about 2 minutes later, the LCD Screen goes back to the Printer Ready Main screen but there is no temperature change.

Does it happen when you issue other tasks, that can overload your power supply? For example, go to extruder menu and set extruder temperature to 200. Will it die? Home all axes from quick settings. Will it die? Set hotbed temperature from extruder menu to 80-100. Will it die? If the answer is yes for at least one question, you may have faulty power supply. You can check whether it continues to produce correct DC voltage when screen is blank if you have multimeter.

@kymber-nichols Change your power supply.

I agree with @FernandoBaltazar. This sounds like a power supply problem (or maybe a loose connection).

@kymber-nichols Yes, maybe a loose wire, try to touch the power wire to sense if not overheating, this indicates a faulty connection.

Unfortunately, up to now, no answers are given on your question! Have you found an answer yourself? If so, you may add your own solution and accept that after 48 hours. If you have not been able to address the problem please update your question so other people may help you find an answer. You can even decide to delete the question. We need to reduce the unanswered questions list to graduate from the Beta stage.


text:
I am looking for laser cut cads for my prusa i3?
I have this prusa i3 printer(I don't know what model is it):

My bed part is broken. And I am looking for the cads to laser cut them! this is my bed pic:

Information about the printer maker/model is crucial. Yours looks like Hephestos 2, so you can try looking here.

The easiest solution would be to have a copy made from the original part using a router. Any woodworking shop would be able to do that.

Your plate support is easy to draw; take a picture from above 90°, and redraw in your favorite cad program. This could be drawn in 30 minutes maximum.

Drawing things using photo alone usually has side effects like millimeter-range projection offsets of the features. Tiny offset of a screw hole - and you will not be able to mount your plate without frustrating adaptations. If you have a part at hand, then better do precise measurements using calipers, it will pay off during assembly stage.

@ZuOverture: I found a part with exectly that size(although design is a little difference), but the holes are same. I will put it's photo.

This is not exactly my part, but the holes place are true. I think if someone measures the bed dimensions( for me it's 21.9mm * 21.9mm) and orders a plate in this size, he can also make holes later with drill(I did it before for another part of my plexi to attach the power supply).
https://www.thingiverse.com/thing:1310778


text:
What are the safest temperatures to heat different filaments to?
I recently backed a 3D printer on Kickstarter, and I would like to 3D print parts for high-temperature applications. So I have two questions;

What's the highest temperature polycarbonate can be safely heated to without warping or releasing toxins?
If there's a filament with better temp-resistance I can print could you tell me? (If you know the highest temperature it could reach safely, that would be helpful too.)

My 3D printer will have a heated bed up to 100°C, and an extruder temp of up to 250°C.

Polycarbonate is heat-resistant up to ~120C. Above this temperature it will gradually become flexible and may irreversibly bend. It will not generate any toxic fumes all the way up to ignition temperature (630C), because it's fumes are not considered harmful. Note though, that with your temperature limit you may not be able to print with polycarbonate, or only do so at a very low speed.
According to the sheets of commercially available printable plastics, PC has the highest printing temperature and heat resistance among them, seconded by nylon. This refers to the FDM printers only. SLS printers may be able to use other materials, even metals like aluminum or titanium, so if you really wish to get temperature-resistant prints, you may look for workshops that have SLS printers and ask them.

Thanks! But can polycarbonate resist constant temperatures of ~ 120 °C, or if exposed for long periods of time will it eventually degrade?

I've never used polycarbonate under permanently elevated temperatures. It will be able to withstand 100C for a long time, because PC coffee cups do exist. As you approach glass transition though, you may expect it to eventually degrade.

PLA coffee cups exist as well. I don't think you can draw any conclusions about the properties of 3D printed materials from the properties of specifically-engineered mass-produced products made from that same material. There's a lot more to it than "it's X plastic, therefore it melts at Y temperature".

@TomvanderZanden, the fact that coffee cups exist proves the plastic is able to withstand that temperature at least. I don't see where I was wrong saying this. 3D printing does not alter material properties to any significant extent.

@ZuOverture No, my point is that it doesn't. There exist PLA coffee cups. Standard 3D printed PLA would not withstand boiling water (but it can be annealed after printing to make it withstand higher temperatures). I'm not sure what the deal with PC is, but just the fact they make coffee cups out of it does not mean a 3D printed object will withstand the same level of heat (and indeed, in the case of PLA, it doesn't).

@TomvanderZanden, if you read your own link carefully, you'll see that those cups aren't made with normal PLA.

Is a greater infill better for high-temp prints?

@Rafael, should be somewhat better. Greater infill will postpone the moment when heated print will collapse inside. Empty print with thin walls will do it very fast.

All plastics have two temperatures to consider for operation and evaluation:

Melting point = the temperature that plastics starts to get soft; this can be considered for maximum temperature operation.
Flow temperature = normally used for molding process and this have a wide range of temperatures depending on PPM´s and mixtures to meet a purpose like coffee cups. Here a link for filament temperature guides

Polycarbonates are the most plastic used for industrial and kitchen appliances. Due higher temperatures support and hardness, so I think is not possible to use polycarbonates in 3D printers due its temperatures are from 250°C to 320°C.

PC can be printed at 260℃ and a bed temperature of 110℃. It can be printed perfectly on 3D printers, you may consider using an all metal hot end though.


text:
Where is .dxf file of this frame(Prusa i3)?
I am looking for this fram, but in github there is no download option for it!
So I did copy the code and paste it, but in result when I measure the big frame's edges it shows bigger 9100mm !! but I think the frame's maximum edge size should be under 45cm?
May someone put's the .dxf file instead of referencing to github page?

There are many variations of the i3, you need to include more information like the github you are trying to get this from.

@tjb1: https://github.com/josefprusa/Prusa3/blob/master/old_single_plate/src/frame/6mm/Prusa3ALU-FREZOVANY-v4.dxf-old

@user145959, press the "Raw" button and save page as dxf. But your description of measurements and photo of your printer from previous question suggests it's not the right part. It's for original Prusa i3, while you own a variation of it.

@ZuOverture: you can write it as an answer!


text:
Prusa I3x and repetier host heat problems
I've saved settings in the slicer for pla and abs, set the default bed temp to 90 and extruder to 185. No matter what settings I select to print with, the bed temp sets to 110 and the extruder to 230 when I send a job to print which I don't want. If I then control the heat manually, repetier or the printer  seems to ignore my requests.
If I try to kill the job I keep getting a box coming up asking me to switch the heats off; I select yes and nothing happens.
If I use the emergency stop the heats switch off.

Can you please include the slicer that you are using, and also the g-code start sequenced (that gets prepended to each print job)?

@james all slicers control your temperatures, set and verify your parameters on each gcode to validate everything is right. Try to send a print that you want not the ones that you don't want to avoid motor and heating stops.

also, there are paramters that slicer includes to "optimize the prints" but these lines need to be changed or removed from extra settings.

What slicer are you using?

You may set the temp in Repetier but when you run the gcode it will send any of the temp settings in the file. So you may set 210 °C first but if 200 °C is in the G-code the printer will take that (as the gcode is sent one instruction at a time). However I also noticed that after the automatic bed leveling any manual settings on the printer are reset to the G-code (I assume the file is re-stating the temp after bed leveling) So I have to override the file temp after the bed leveling is complete.
I now use OctoPrint and it has a cool feature : temp offsetting, you can specify an offset for every temperature the OctoPrint server sends to printer; e.g. in your file it is set to bed: 110 °C and extruder: 230 °C you can tell OctoPrint to take 20 °C off all bed temps sent and 45 °C off any extruder tempperatures sent. It's great for tweaking the temperatures of your G-code without editing or re slicing, just change the temperature offset and reprint.
I noticed on a previous firmware version for the I3 mk2s Repetier did not connect properly to the printer this problem disappeared in the latest Prusa firmware (v3.1).  One of the symptoms I noticed was the temperature settings were not taken by the printer.
Some slicers have a setting to have sticky parameters, i.e. set temperature once don't bother re-sending. However if this was turned off, it is possible that the generated G-code repeatedly send the temperature settings with every instruction, continuously resetting and overriding these values. (OctoPrint temperature offsets would correct this)


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I am looking for the aluminum profile parts specs for this prusa i3 printer?
I have seen some photos of aluminum based Prusa i3 printers, and I like to know the numbers and the specs of the profiles? Also I want to know Is the first pic strong enough for reliable printer or I must use the second(respect to profiles I mean).

A printer design like this would benefit a lot from a diagonal bracket to stiffen up the vertical part.

They are 2020 (20mm x 20mm) T-slot extrusions. They should not be confused with V-slot extrusions, which are similar to T-slot, but have a 45-degree slot profile to accommodate V-slot wheels.
If you are contemplating a new build, I would recommend using V-slot. Note that T-slot and V-slot come in a number of sizes (in multiples of 20mm). A 2040 profile is 20mm x 40mm, and will have two slots on the wider sides. Other sizes are available, such as 2060, 2080, 4040, and even C-shaped profiles.
You may want to use 2040 profiles for greater rigidity, especially if you are contemplating a large build volume.
Note that there are imperial as well as metric T-slot profiles. RepRap uses metric profiles.
ReRap Wiki: T-slot
OpenBuilds: V-slot

The specs for 2020 aluminum profile is here.
https://8020.net/20-2020-black-fb.html
This site even has the cad profile files for download.
I have noticed that some people have suggested using V-Slot from
open builds... however, V-Slot has a V for the V groove wheels which this design is not using so in my opinion there is absolutely no reason to pay a lot more for V-Slot when your not even using V groove wheels.
I have also noticed that some people have suggested using 2040 T-Slot and the
link above has a search and you can find the profile for 2040 T-Slot.
I agree that T-Slot could be better; however, I would build first
with 2020 T-Slot to see for yourself and then report your findings after
upgrading to 2040 T-Slot. My guess is that you will find that 2020 T-Slot is enough if you use the recommend corner brackets... if your planning on using 3D printed corner brackets... then it might be necessary to use 2040 T-Slot.

It can really depend on where you are in the world. A few years ago, I was unable to obtain standard V-slot (& T-nut) 2020 extrusion, at a reasonable price, and so I ended up using an extrusion from a local supplier instead, and managed to obtain 6 m of extrusion for only $15!
My aluminium extrusion has this profile, which has V-Slot style grooves.

Also, it uses simple, and cheap, M5 nuts, rather than T-nuts, which are much more expensive (comparatively)
Please see Will standard M5 T-slot nuts fit these different 2020 aluminium extrusions?, for more information.
You can also use 1515, depending on the size of the printer... if you have a larger printer design then you can always double up and use two adjacent lengths of 1515 to effectively have 3015 (or 2040 - if using two pieces of 2020). Basically use whatever is available and cheap, it isn't necessary to pay a lot of money, just to have the perfect extrusion profile. Remember that you are designing/building the printer yourself, so you will have some leeway. Other sizes that may be available to use are 2525, 2040, 3030, 3060, etc..
However, if you are using 3D printed parts for the frame (such as the end or corner pieces), then you may be restricted in what type of extrusion that you can use, by the printed parts themselves and what type of extrusion they will fit. However, if you are only using aluminium parts for the frame (including aluminium corner brackets/braces) then you should be OK.


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Project help, printing a Neopixel enclosure to secure to a car rear windscreen
I haven't purchased a 3D printer yet, I've been working on the software and electronics for my project and now I'm about ready to get a printer, haven't decide on which yet.
Recommendations welcome.
My project will put 3 rows of Neopixels on the windscreen of my car, attached to the top inside.  I intend to print the container in sections that will slow together.
I want to allow for the curvature of the windscreen in the design of the container and this is my question, I want to design a container that will hold 3 rows of Neopixel strips, thats the easy part, I want the container to fit neatly against the windscreen with no gaps, how do I work out the curve of the windscreen so I can put this onto the enclosure ready for printing?
The enclose will be as wide as the read windscreen and split into printable sections that will slot together for installation.
The car this is going into is an Audi A5 2012.

I'm not entirely sure what your question is. How big are the pieces that you want to print?

There are 3 rows of NeoPixel strips arranged one over the other with a gap between each row of approximaltely 2 mm.  Each row contains 62 pixels.  The entire strip will be large enough to span the rear windscreen, I plan to print segments of the entire enclose the size of each will depend on the printer chosen and what size it supports.

I know this is an old post, however since creating the post I've progressed a lot and in the end the solution was quite simple....Using a peace of wood which I position across the back of the windscreen, I measured at regular intervals the distance from the wood to the screen.  I then plotted this in Autodesk Fusion 360 and produced an accurate curve of the windscreen, then then split this into printable sections and it fits perfectly.

There's a handy tool for replicating curves that use a series of plastic or metal fingers in a sliding mount. One presses all the fingers to one side, then presses the bracket to the desired surface until all fingers are in contact. The opposite side now represents the measured curve and can be traced into a modeling program.
For your purposes, that is unlikely to work, as the tool is perhaps six inches long, far too short to span your windscreen.
Consider the following:
Attach a string to each edge of the windscreen or wedge a thin rod from one side to the other. This provides you with a straight line reference. Measure as nearly as possible to perpendicular from the reference string to the windscreen surface. I have a laser measuring device that has 1/16" or 1 mm accuracy above certain distance, which would not work well in this case as you approach zero at the edges.
Start in the center, record your measurement, and move an appropriate distance outward. I suggest you need only approximately 20-30 mm spacing as you are collecting points on a curve, which are likely to be relatively uniform and easily reproduced in software.
Your graph now has zero, zero on the left, and say 750 mm, 40 mm on the right, with matching numbers in the middle. On real paper, turn it into a graph, or use a suitable vector editing software such as Inkscape and duplicate it there.
Depending on the shape of your window, you may have to replicate the process at different heights in order to get a proper representation of the curve of the glass.
Once you have the dots, run a Bezier curve through the dots. The resulting like can be extruded or otherwise converted into the segments necessary for your 3D printing project.

Thank you, was you laser measurement tool expensive?  Sounds like a good plan.

I found lots of laser measurement devices on Amazon, thanks.

Be sure to check the specifications for minimum distance with the laser. I don't recall what limits are on my Bosch version, but it's not practical to measure near zero. For your requirements, a mechanical device like calipers may be better suited. The depth measurement feature of an inexpensive set of Harbor Freight calipers would give you suitable accuracy as well.

I was thinking of making up something simple using one of these: HC-SR04 as it will be very short range, 30mm max.  I could rig up a bar with the range finder taped to a bit of tube that slides along in front of the rear windscreen.

Just ordered this: https://www.amazon.co.uk/gp/product/B01CU2MCM4/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

I don't think that will help with taking the measurements, but it certainly will help with producing the parts. Your choices for software are many. You'll be able to use (free) Fusion 360 or similar. I'm fond of OpenSCAD, but with the complexity of the shape you'll have, any program may be a challenge. Aim for a parametric software, as you'll want to be able to enter your data, not drag and draw, so to speak.

I'm quite familiar with Autodesk 123D, lots to lean now, will use the printer to make up a tool to help me mount the HC-SR04 on a rail and slide across to take measurements.  The tool will create an ASCII file of measurements which I will import into 123D to make a polyline.

I've not used Autodesk 123D and from this link https://www.autodesk.com/solutions/123d-apps, I understand why not. "Autodesk is no longer offering Autodesk 123D" and the first suggested replacement if Fusion 360! I expect you'll find Fusion 360 to be similar in many ways, reducing the workload of your learning curve. Tutorial videos abound.


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My 3D printing part starts to bending after about 1 cm height and blue tape separates from bed
I use a Prusa i3, and this is ABS printed part with 225/90°C. Why did this happen?

I tried to print this part again with new settings on Slic3r (I used Cura for previous print), but I got the same result. I found that the problem is because the model starts to bend after about 1 cm height. Also the blue tape starts to separate from the bed.
I don't use the fan for printing part (although the MK8 extruder's fan works all the time), and the temperature for the new part was (225/85°C first layer and 220/80°C for other layers). Also I must say that the adhesion of the model sticks to the bed is very good and strong, but it is bent!

ABS is a royal pain to work with.  About all I can suggest is to build an enclosure and try to keep the entire workspace (air volume) as warm as possible

Enclosing Prusa i3 completely puts mainboard and PSU at the risk of overheating. Don't do it before you ensure proper cooling for your electronics.

@user145959 tapes unstick after long periods of heating. High temperatures are good only for first layer to get adhesion.

Multiple problems here. Let's try to isolate them.

Blue tape. Good for PLA, not suitable for ABS. ABS works fine with kapton tape, glue stick, hair spray, ABS juice over glass, aluminum or PCB epoxy composite board.
Always use at least brim feature to ensure good adhesion along the edges (your last photos have none). For parts with small hotbed contact area use raft.
Hotbed temperature should be 100°C+, because at 80°C adhesion is weaker. If you can't raise hotbed temperature to 100°C, think about thermal insulation.
Layers of plastic don't stick to each other. Either plastic comes from extruder being already cold (check that there are no draughts of cold air nearby), or you're printing too fast (50 mm/s should generally work, if not try 30 mm/s).
No infill between walls. Either it is set to 0 or optimized out by some option.
Round walls aren't round. Either printing speed problem, or your belts are loose.
Underextrusion. Bottom of your first print looks like mesh rather than solid surface. Check that plastic flow is around 100%.

Also check that your thermoresistor measures the actual temperature of the extruder (i.e. is in direct contact with it). Otherwise you will get overheated plastic extrusion, which looks like your first photos.
Also, print a 1 cm cube first. Don't do anything complex, just cube.

My best results with ABS have been with a hot bed (100 degrees C), and using the "acetone/ABS slurry" to stick the print to the bed.
I was not able to get ABS to stick well enough to blue tape at low bed temperatures, and at high bed temperatures the blue tape would sometimes separate from the bed.
The ABS slurry is applied to the cold bed, and gives you an ABS film intimately attached to the bed.  It will be a thick enough film to carry the color, so it is best to make the slurry with the same color as you will be printing with.
There is no absolute ration of acetone to ABS that should be used for the mixture.  In service, the acetone evaporates.  A thicker slurry will leave a thicker coating.
I use flux brushes (sometimes called acid brushes) to apply the slurry, although one can also use a watercolor brush, or just pour a small puddle on a bed if it is level enough to not run off the edge.

Try putting your printer into a heated chamber, and when the print is finished, slowly decrease the temperature of the chamber. I would also recommend using putting something like buildtak or printbite onto your buildplate. If you are not able to do that I would recommend putting some purple gluestick onto the bed, or a few spritz of hairspray should do the trick.


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Should I be doing PID auto-tuning with my fan at 100% (Anet A8)
I'm using an Anet A8 with Marlin 1.1.6.
I've read countless guides on PID auto-tuning and never saw that the fan needed to be on, but when I look at the Marlin source code's ANet A8 configuration (here: example_configurations\ANet\A8\Configuration.h) it states:
  ...

  // ANET A8 Standard Extruder at 210 Degree Celsius and 100% Fan
  //(measured after M106 S255 with M303 E0 S210 C8)
  #define  DEFAULT_Kp 21.0
  #define  DEFAULT_Ki 1.25
  #define  DEFAULT_Kd 86.0

#endif // PIDTEMP

So, should activate the fan before running the auto-test if I wish to update the PID values in Marlin for my Anet A8?

You should run the fan at what you expect it to be at the majority of the time it is printing.  If you tune at 100% fan and never use a fan then it will be too aggressive, if you tune at 0% fan and use the fan then you will struggle to maintain/reach temperature.

Thank you, that completely makes sense and I think is an important tidbit that all bazillion of these guides should mention.

One last (possibly stupid) question: does it matter if there is filament in the printer when Auto-Tuning?

Ideally I'd think you should extrude when you tune but I'm not sure if that is possible.  Having filament in might help but most of it is going to ooze out as it heats up anyway.


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How to remove internal part of a hex grid
I am modelling a few cut templates to be used on an hexagonal grid (honeycomb) material using OpenSCAD.  Basically, from a reference cell, I need to select all cells that are within a given range and given angle.
I implemented this by creating an in memory grid that covers an area larger than what I need (extra range, 360 degrees), and then testing each cell for both the distance and angle requirements, extruding only those that test positive for both conditions.
Everything works as expected...

...but now I would also like to add the possibility to have the outer contour of the template without having each individual cell within it (so, a single thin line going around the whole "pizza slice" above).
I'm pretty new to OpenSCAD: what would be the best approach here?
(I'm happy even with a solution that requires to re-implement what done until now).

Are you looking to generate a convex hull, or do you just want to remove all the internal edges?

If you are unable to find a solution here, consider to join the openSCAD mailing list/forum as there are some quite skilled and talented brains who are really on top of things.

@Mick - I'm not sure I am knowledgeable enough to understand your question (I lack the terminology), but I already tried the hull() function (if that is what you were going for), and it does not do what I want, as it doesn't contour my shape, it "wraps" it by making a straight line between the most protruding points of each side of it...

I ended up finding a reasonable solution myself:

Basically, I diffed two identical, non-hollow geometries, in which the first one had the cells larger than they needed to be (so overlapping with others), and the second one had them exactly of the right dimension:
difference() {
  base_geometry(range, angle, infill, extra_padding = 2);
  base_geometry(range, angle, infill, extra_padding = 0);
}

This way the only portion of the solid remaining was the extra_padding on the outer edges of the geometry.

Now I understand what you were after. I was going to ask you to provide a drawing, but you've done a lot better than that.

Unfortunately, OpenSCAD does not have a 2D hull() transformation, although it has been requested. You might be able to find a pre-written package that implements a 2D hull. However, if all you want is a hexagonal grid with a border of some arbitrary shape, could you not cheat, and get your slicer to generate the grid for you? All you would need to do is generate the envelope, and then slice with a hexagonal grid as in-fill, and request no top or bottom layers. Most slicers will do hexagonal in-fill.
If you want to do it all in OpenSCAD, then I would go about it like this:

Create a 2D grid, similar to what you have now.
Create a 2D outline of the shape you want, undersized so that you can add a manifold (as a perimeter).
Duplicate this shape.
Add a manifold to the first copy.
Create an intersection of the second copy and the grid.
Create a union of the two copies.
Extrude the union.

I believe I failed at being clear enough on what I want to achieve (sorry, I lack the proper terminology from CAD and/or mathematics): I don't want the internal grid at all.  I want only the perimeter of the shape I generated, as in: the external, non-adjacent-to-another-hex, sides of the hexagons at the edge of my surface... There is something interesting about your proposal though, maybe part of the solution I am looking for... and that is: adding manifolds.  How can I do that, having an existing geometry?


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Adding points to a point cloud
I made a scan and got a cloud point file, but the cloud point is not that good, but I need to print it in a 3d printer as soon as possible, just to see how it would look.
Basically it's missing some points that were not scanned properly due to it being transparent at those points. I'd like to add those points manually (using meshlab preferably) and create a surface with them .. something that makes this file printable.
I know I could edit this file manually since it is an ascii file with the values of xyz .. but that is a lot of trouble and certainly there is a faster way to do this with a free tool.

A good free tool for editing meshes would be Blender. Linux, Windows, Mac are supported. It has a serious learning curve, and is somewhat counter-intuitive in use (right click object to select) unless you customize it.
Plenty of online video tutorials to learn the basics, though, and if you have a membership for Lynda.com, those videos are the best (opinion).
I've used it to pull edges and vertices together, to chop out pieces that weren't supposed to be there, etc. The flexibility and power of the program is amazing, considering the price.
Many artists use the program for creating 3D animations and full length movies. Amazing talent, well beyond my capabilities, but it shows what the software can do.
The website also has links to tutorials and the manual, which is also a work of art.

If you can devote the time to learn the program, anything 3D modeling related will be within reach.

yeah ,,, pretty steep learning curve. I started meddling with it and was able to do something ... but it was so bad I wouldn't dare continue


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How can I prevent my nozzle catching on my print?
I have created a budget 3d printer using parts of old computers, specifically I used the CD drive mechanisms for the x,y and z axis. This printer is similar to the curiosity E-Waste printer, as seen here: Link
After quite a bit of time working on it I have got to the point where my printer should be able to print, but unfortunately, I have encountered an issue.
The layers in which the printer prints fluctuate in height, and so when the nozzle travels over the lower layers to do the next layer, it hits a bump, misses some steps and becomes mis-aligned. I have never owned a 3d printer before, but I think that it is likely that the problem I have which causes the prints to not be flat is likely a common 3d printer problem. However, with  commercial 3D printers, these bumps would probably only cause a drop in the quality of the print and not a complete fail; it is only due to how weak my motors are that the nozzle will miss a step with even the slightest force against it.
I have thought about why the layers may not be flat and I have come up with a few possibilities that I think are the problem. I do not know if these are in fact the source of the issue, but these are the things that I have considered so far.

The nozzle height when starting the print. If I lower it then the layer height will be smaller, and so there is less chance for it to be higher in different places. However upon testing this I found that, due to the reduced height upon the first layer the nozzle would get stuck.
When the nozzle changes direction, for example at the edges of the print, there is significant vibration and it is possible that this cause the filament to overlap and not be flat. The vibration is due to the nature of my printer and would be very hard to reduce. A solution could be some kind of software fix, but I do not know enough about this to do so.
Maybe the speed at which I am printing is not good. I'm printing currently at an incredibly slow 40mm/s.I have tried different speeds but at low speeds there is over extrusion and at high speeds, the vibration is too much.
I have tried experimenting with flow rate (100%,75%,and 50%) and at the moment I am using 50%. This is because my extruder motor is a bit weak and often misses steps, also the filament requires considerable force to push it through. Is this normal?. My idea is that maybe there is too much filament being extruded and so if I lower the flow rate the print will not create bumps.
The filament curls slightly when it comes out of the nozzle and I have tried to fix this by cleaning it and printing faster but it is only reduced. I'm printing at 200° currently; Will higher or lower print temperatures cause the filament to curl less and be more easy to push through the hot end?

As you can see there are a lot of factors in which I need to consider if I want my printer to be able to print correctly. And unfortunately, with my printer it is either perfect or a failed print; there is no in between. Due to the weak motors everything has to be exactly right, or the nozzle will get stuck.
I am not sure how to add videos here so I will instead. add some photos of the prints, and three photos detailing how the prints fail.
Below is an image containing the 6 most recent prints in which I played around with the different factors mentioned above. The top middle one is the most recent one. The object i am trying to print is a simple cuboid.

This is what the first layer of my most recent print looked like. There is some kind of gap in the middle for some reason, but I don't think that is the source of the error. The print appears to have adhered well, at this point and it is relatively flat.

This is what the second layer of the print looked like, notice how the lines are wobbly and not very neat. There is also a small area of higher height in the bottom left corner which inevitably causes the nozzle to get stuck.

This is the print after the nozzle hit the now cooled down blob, missed some steps and then was misaligned. It then goes on to print the next layer in the wrong place and gets stuck very badly.

Thank you, for reading this. Any help would be much appreciated

A printer must be working very well to not have the problem with the head hitting against small verticle protuberances and losing control of the X and Y positions.
Some factors I've found that make bigger bumps.  If you have any of these, fixing them will make the problem better.  From observation, it is ultimately the power of the motors, the ability fo the nozzle to melt through small bumps and the resilience of the mechanism (not something that is otherwise helpful) that let decent prints proceed.

The first layer may not be the height you expect.  First layers are
typically 100% filled.  If you are extruding too much plastic for
the layer height, it has to go into a bump.  To fix this, check your
vertical height.  Measure with calipers the height of the flat
portions of a 1-layer print, and compare that with your slicer
expectation.  Adjust the vertical offset to make the actual meet the
intended.
You may be extruding too much plastic.  Depending on your
slicer, you can adjust this by tweaking.  I user slic3r, and can
adjust the filament diameter.  Overstating the diameter causes
under-extrusion.  Understating the diameter will cause over
extrusion.
Sometimes the bumps come mostly at changes of direction.
This is possibly caused by several things, but I'd look first for
backlash.  The mechanism should be tight, and not move under
moderate side-to-side or front-to-back force.  If it jiggles, it
will can cause problems.  Wiggle it.  Look at what moves.  Should it
move?  If belt driven, the belts should be tight.  If driven with a
lead screw, the nut should not move and the screw should not move.
If they do, fix it somehow.
If you are running the motors near the maximum speed and/or
acceleration, their torque will be lower than if they are running
slower.  Try slowing everything down by a factor of two and see how
the problem changes.
It might help to print at a higher temperature, so the nozzle can
melt through the bumps with less force.  This could cause other
problems, but if you are marginally cool now, warmer might work
better.

In slic3r you have a specific parameter for under/over extrusion. Also, it seems like there is way overextrusion going on.

Is your hotend attached at all? It looks like it's just clipped onto the fan, that can't be good in the long run (IMO).


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Printing a part from two materials
I am trying to print a large part from PolyPro but can't get it to stop warping when I remove it. It also doesn't stick well. I have tried playing with printing speeds, temps, extrusion % etc. Even tried putting packing tape on the bed (which helped it stick but didn't prevent the warping).
I thought I might try printing a base layer (2 mm) of PLA, the print the rest of the the part in PP right on top of it. The PLA hopefully will stick and keep the walls of the part straight. My question is how to do this. Is it as easy as cutting off the bottom 2 mm of the part and telling the design software that the part rests 2 mm above the bed, then tell Cura not to print a support?

Why not only pause your print after 2mm, change the filament and resume your print to be completed?

If your part warps after you remove it, then it might be a part design problem. Please attach links to the photos which show how it warps.
Also, your method with 2mm offset will result in a mid-air first layer, which never ends well. Follow Fernando's advice here.

You could just let it print the 2mm you want for the base, then pause the print and change the filament to PP and then resuming the print after you change the filament.

If PP prints at a different temperature than PLA, you would want to adjust the temperature while you are changing the filament.