Gluing PEI to Borosilicate Glass / 3D Print Bed Surface

Ok here goes round two. Ok so this is round two. I managed to ruin a piece of borosilicate glass and PEI plastic the first time around.

The adhesive which came with the PEI is called 3m 468mp – and it was supplied cut to size with the plastic which I bought mine from Ebay. Ispopronal. It has a jelly like consistency – so it’s quite easy to rip if you’re not careful.

It’s also very tacky, and will stick to anything, so once it’s down, don’t try and peel it off.

PEI is also known as polyetherimide. I’ve noticed it on oyster card readers while going around the transport system in London. It has a distinctive greenish colour and is UV and heat resistant.

From the reading I’ve done, this seems like the best stuff to use as a print bed, but I have to stick it on a piece of 3mm borosilicate glass.

Borosilicate is a thermal resistant glass – and notably the vessel for hot cup of earl-grey drank by captain Picard in Star Trek the next generation.

It goes without saying if you are going to build a replicator, you need borosilicate, hot.

It is also flat and will resist warping unlike the aluminium heat-bed.

So, a little earlier I applied some isopropanol on a cloth to the surface of the glass, to clean it before carefully applying the adhesive – a few cm at a time, using a clean metal painters scraper to push air bubbles out as I went along.

Meh that’s not bad.

I then cut the excess off – which left some little bits of adhesive on my blade and on the cutting mat.

I peel the protective layer off the PEI, and clean that with some isopropanol. I then repeat the process.

To help me line up the pieces I use my engineers straight edge as a starting line. That is about 6mm thick so I have plenty of height to rest the PEI against it.

Once the first section has stuck on, I get my painters scrapper and use it again to pull any air bubbles out.

So some advice before trying to do something similar, avoid drinking too much coffee so your hands are not shaking. Do this while you are awake and not at the end of the day when you’ve been concentrating on lots of other things. Be patient. Clean your surfaces before you join them. Use something like the straight edge to help you line up your pieces. And maybe don’t work on a glass chopping board because everything was sliding around.

If you want to watch my assembly and review of the Anet A8 3D printer I’ll link to that at the end of this video, and don’t forget to check out other videos on my channel which are CNC related at the moment.

Thanks again for watching.

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