Which hotend does not clog and is good to use with a Bowden 1.75 mm setup? I'm building my own 3D printer (custom design, made by me and cut using a water cutting machine) but I have always had problems with the hotend clogging.

I have had four hotends:


a J-Head;
a full metal;
a full metal made by me and;
my current hotend which is just a block of aluminium with a plaster cold-end 100% homemade with no precision at all.


Believe it or not, this hotend is the only one that has finished a whole print (about 40 minutes), all of the others, with or without fans, haven't managed to finish one!

Well... this hotend has a 1.5mm hole so I guess that that's why it can print.

The problem with all of the others was that the 1.75mm PLA that I'm using clogged the hotend after two minutes.

Now I would like to buy a new, more precise, hotend. I'm using a Bowden extruder, can you suggest a good hotend?

This is my printer:
To make the suggestion of Martin Carney a real answer and shift things away from comments:

Yes, moisture and dust can be a problem. Find elaborations on the moisture here:
Does filament have to be stored in an airtight environment.

Also, dust getting into the hot end won't make extrusion easier. (link with suitable information needed). There are filament cleaning 'devices' for print on thingiverse, have a look at things with the tag: filament cleaner.

There are some other things that are mostly discussed in relation to hot-end clogging, which are printing speed, retract setting and what I would call hot-end resistance. For all of those, read through this thread and refine your question according to what you tried and what the results were:
Repeatedly Clogged Printrbot Simple Extruder.