Troubleshooting poor adhesion at the edge of the bed I've been printing for a week now on my new printer and have been getting great results, including great adhesion. However, most of my prints have had a fairly small footprint.

Now, I'm stepping up the types of items I'm printing, and I've started to run into a problem. Long, thin parts are starting to lift off the bed, especially at the edges of the bed.

I've read the question dealing with this issue with ABS and realize some (most) could apply to me. However, I'm printing entirely in PLA on a non-heated bed.

My question is: What is the best way to go about troubleshooting this problem? In which order should I attempt fixes to narrow down the problem most quickly?

Printer: Monoprice Maker Architect 3D (Very similar to Makerbot)

Material: PLA

Heated Bed: No

Bed Material: Something similar to BuildTak on top of an acrylic bed. (The sheet of material came unlabeled with the printer and I haven't been able to track down exactly what it is.)
There are several things you could try without spending much but even PLA will warp on an unheated bed.  I had a Legacy Kossel that I switched to an acrylic bed and had many issues with warping and prints pulling off the bed.  

Some cheap things to try would be...


Adding a brim to the print.
Blue painters tape on the acrylic, remove the other material if doing this.
Place cheap piece of glass/mirror on bed and use hairspray/gluestick.
Use hairspray/gluestick directly on acrylic.  You must be careful here because first layer height is very critical to prevent damage to the acrylic from the plastic welding.  A layer of hairspray or glue should prevent it but dial in your height before printing.
If you aren't currently using a fan, you could try sealing the sides to prevent drafts.  I doubt this would change much since you are using PLA but it's an option.
If these are your designs, there are steps you can take to reduce warping as seen here.


Also many other suggestions here.