Make Your Prints Stick to Your Build Surface!

When I built my printer, I was so excited to get printing! I knew that 99 times out of 100, the filament doesn't stick well to the glass that you put on your heated bed. There are a lot of ways around this, including (but not limited to) blue painters tape, kapton tape, hairspray, and even a ABS/Acetone slurry. While getting started I purchased some blue painters tape, which worked decently well, but not consistently. I never seemed to know when a print was going to pull form the bed, and soon it seemed like I had to babysit my printer for fear that prints wouldn't stick and I would loose hours of progress. I quickly moved to the ABS/Acetone slurry, which worked a little bit better, but I was tired of constantly applying the substance to my print bed, and cleaning up after it. I also went through a lot of acetone. It was time to look for something more permanent.

Then, my friend (AndJoeG on instructables!) suggested that I try PEI. PEI (Polyetherimide) is a thermoplastic that does a great job of holding a print when heated, and releasing it when cooled! Sounds perfect! The best part? You don't need to constantly change it. Just wipe it down with acetone every now and then and you are good to go! This will save you loads on materials you would have otherwise put on your printerbed, and instead you just get to sit back, relax, and print away!

Step 1: Materials

Here's what you need to make your prints stick like a dream!

PEI
- It needs to be the same size as your print bed, I found a 12"x12"x.03" sheet off of amazon for about $17
Cutting tool
- Your PEI shouldn't be too difficult to cut, but I would recommend a box knife, or x-acto knife before scissors.
Acetone
- It's always handy to have a bit lying around to clean off your build surface every now and then when it starts to get dirty. I had a bunch leftover from my failed ABS slurry attempt.
- side note: if you do use acetone, make sure it is NOT nail polish remover. That is actually a mixture of acetone and other oils and minerals which will do nothing to help your print stick!!

A quick note: this instructable assumes that the maker already has a glass print surface and heated bed on their printer, if not, shoot me a message in the comments and I can help you with your printing problems!

Step 2: Cut the PEI

The first thing you need to do, once you have your supplies, is to cut your PEI to size. I laid out my sheet of PEI and placed my glass print bed on top. Then, using an x-acto knife, I traced the outside of my glass print bed onto the sheet of PEI.

I then made lots of passes until I had a deep score, and finished it off by using sharp scissors to cut my 8" x 8" square of PEI! Remember to always take caution when using sharp tools, x-acto knives may seem harmless but they can be extremely sharp.

I checked the fit on top of the glass print bed and it was perfect!

Step 3: Prepare Your Build Surface

Now that your PEI is cut to size, you're going to want to choose which side you want. If you look closely, you'll see that there is a matte side, and a glossy side. Here's the difference between the two:

The matte side is going to give a really good stick but lesser quality bottom of print (as in, the base of your print won't look as pretty). This side requires a bit less care than the other, just clean it up with some acetone to get rid of any oils from your hands, and it's good to go!

The glossy side is going to give you a really great quality bottom of print. The base of your print will look very nice and smooth. This side requires more care, as it isn't as easy for the print to stick here. You will probably have to clean it with acetone or isopropyl alcohol between each print just to keep it pristine.

I chose to use the matte side to print on because i didn't want to have to clean my surface after every print, and didn't care so much about the quality of the bottom of my print.

Peel away the plastic on the opposite side (for me, the glossy side), and place your PEI on top of the glass print bed (be sure that the glass is cleaned and free of debris) such that the desired side is on top. Then gently peel away the plastic on that side.

Now, use binder clips to secure your glass print surface to your heated bed. Try not to touch the PEI as much as possible so it stays clean, but once it's secure go ahead and gently wipe it down with acetone (or isopropyl) anyways to get rid of any oily residue from your hands.

Be extra careful to NOT SCRATCH THE SURFACE OF YOUR PEI, scratches are your worst enemy here, so take caution!

Step 4: Start Printing!

Now you can start printing!

BEFORE YOU PRINT BE SURE TO LEVEL YOUR PRINT BED! IT IS NOW .03" HIGHER THAN IT WAS BEFORE! Don't let your nozzle ruin your brand new PEI by dragging across it first thing!\

Keeping this in mind, go forth and print! You still need to heat up your bed as usual, but watch in amazement as the prints stick right to the PEI! When you have finished your print, let your bed cool down to about 60C or 70C until you try to take your parts off, I generally can just pop them right off without any issues, but if they are particularly sticky wait until your bed cools further. If it is at room temperature and your print is still stuck, cool it down further by sticking the PEI (and print) into the fridge! You really shouldn't get to that point though, I have yet to have issues getting my prints off the bed.

For my first test print, I downloaded http://www.thingiverse.com/thing:761744 from thingiverse user amaochan. It's an awesome moveable rhino! I had had trouble getting it to stick to my print bed previously but I had no problems with the help of PEI.

This was actually one of the greatest improvements that I made to my printer thus far. I no longer have to worry about anything sticking to my print bed! I highly recommend this upgrade!

Thanks for reading, and a huge thanks to AndJoeG for this life changing recommendation!