PEI Bed Surface

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kazolar
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Joined: Wed May 13, 2015 4:39 pm

PEI Bed Surface

Post by kazolar » Tue May 26, 2015 5:56 pm

Since no one has mentioned it (at least not that I can find), I thought to start a topic on PEI print bed surface.
I've been using PEI virtually the entire time I've had the M2, and I simply wouldn't go back to bare glass, tape, glue stick or anything else.
I'm using a 0.06 thick piece of PEI laminated onto a piece of Boro glass with 3M 486MP tape. I used 2 inch wide tape, as it makes application a bit easier. I laminated the 12x12 piece of PEI onto Boro, then used an exacto knife to carefully trim it -- run the knife along the PEI a bunch of times until it's almost all the way through and then carefully snap.

If you get the bed leveled out -- I'm not sure you can beat it for adhesion.

So far, I've printed PLA -- perfect at about 55-60C bed temp, smaller prints in the middle I can get away with 50, for a print using 30+% of the bed, go to 55, for 50% or more go to 60. Anything above that is diminishing results as it makes the print harder to remove and is not necessary. I've printed large objects, using virtually the entire bed with no warping, or peeling or any adhesion problems at all.

ABS -- I've settled on 95C -- again, smaller prints in the middle can get away with 90 or maybe 85, but with ABS it's much easier, go at 95, and then wait for the bed to cool and the print just sorta falls of the bed with a light push.

PETG works super well, I've used 50C and have really excellent adhesion, no problems.

If I print ABS, after the print I clean the BORO with acetone, then 99% isopropyl. For anything else just isopropyl is enough.
I've sanded my PEI with 1000 grit sand paper a few times to get the shine out of the prints and to make the adhesion a bit more uniform. For a piece of the thickness I have, it will take a good long while for me to need a replacement.

Other tricks is a can of compressed air, works really well to spray a bit on the bed near the edges of the print when I'm in a hurry and can't wait for the bed to cool down on it's own.

I haven't tried any flexible stuff yet, that's next -- my understanding is that it adheres to well and the option there is to simply flip the bed boro side up, alternatively is to use some oil on the PEI to help it release, not sure yet.

If anyone is interested or has tried PEI. I'm curious to know your experience.

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PcS
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Location: Michigan

Re: PEI Bed Surface

Post by PcS » Tue May 26, 2015 6:17 pm

I tried twice to stick it to the boro....first time failed miserably ....had to remove and redo....second time went well but it is not flat enough...apparently still some unwanted air bubbles. I gave up for a while on it. When my sanity returns....if it does....I will give it another shot !

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Jules
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Re: PEI Bed Surface

Post by Jules » Tue May 26, 2015 6:24 pm

Bought a piece to try and cut it to size, but haven't applied it yet. :D

kazolar
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Joined: Wed May 13, 2015 4:39 pm

Re: PEI Bed Surface

Post by kazolar » Tue May 26, 2015 6:25 pm

My first 2 attempts were not good either. Make sure you apply the tape evenly. If you see bubbles under the tape, try to pop them with a knife before apply the PEI. If that doesn't work -- start from scratch. Took me about an hour or so to get a good lamination. I didn't want to go with the thinnest piece available (0.03) -- I went with the next one up, it has a bit more substance/rigidity in it. Mine is flat, I have noticed a slight bow in the middle, but I've seen that with regular Boro as well, but that can be corrected with clip placement.

For a good lamination its very important to get rid of the air bubbles under the tape so apply it carefully, I used a credit card to apply the tape, then remove the protective film from the tape and popped a few bubbles and then just drop the PEI sheet straight down and press (sit on it or whatever)

Good luck.

kazolar
Posts: 43
Joined: Wed May 13, 2015 4:39 pm

Re: PEI Bed Surface

Post by kazolar » Tue May 26, 2015 6:27 pm

Jules wrote:Bought a piece to try and cut it to size, but haven't applied it yet. :D
I recommend to laminate first, then cut with an exacto knife after it's on the boro and you have it laminated well. It's really to hard to get the corners lined up perfectly, so just drop piece down, and then take your time to trim by running the exacto knife on along the boro edge about a hundred times (good forearm workout).

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Jules
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Re: PEI Bed Surface

Post by Jules » Tue May 26, 2015 6:44 pm

[/quote]...... running the exacto knife on along the boro edge about a hundred times (good forearm workout).[/quote]

:lol: :lol: :lol:
Amen! After 20 minutes or so of fruitless forearm workout I threw in the towel, scored it with a plastic cutter and snapped it. (Perfect results.)

So, since I've already cut this to size, do you think floating it on with the slighty soapy water will be the best application method to try?

One of the reasons that I hadn't put it on yet is that the plastic had warped visibly from transport through the heat. (Or something.) I've had it sitting under a pile of books to flatten it out a bit before putting it on. It's better now, but I'll leave it under there for a while longer....putting the whole pile out on the driveway one afternoon would work faster, but it's been raining cats and dogs here for about a month now. (sigh!)

kazolar
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Re: PEI Bed Surface

Post by kazolar » Tue May 26, 2015 6:56 pm

I tried with soapy water by floating my first attempt. I was hoping to only need to cut 2 sides, didn't work for me. At least not that way, it stuck on wrong and it was a pain to remove the adhesive from the boro. That's why I went with the drop and cut approach.
PEI should not be warped that bad. Mine was basically flat. I bought it of amazon. I recall for about $30. If you lay a piece of 12x12 PEI on a table it should look flat, if it doesn't, I wouldn't use it. It may warp prints or pull on the boro too much. Figure with abs you are applying 100c to it or more for many hours. I've done several long prints 30 hours being the longest (PLA) followed by several 16 and 17 hour prints, with the bed cooling down just enough to remove the print. So the initial application needs to be spot on, or it will lead to more frustration.

If you get a good application, I have it now calibrated where my wife can just go to the basement, pop the print off wipe the bed with alcohol, and I can start the next print remotely. Mind you might wife is a stay at home mom with a 20 month old toddler, so when I say it makes it easy, I mean it makes printing easy.

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PcS
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Location: Michigan

Re: PEI Bed Surface

Post by PcS » Tue May 26, 2015 7:39 pm

Float method will not work !!!! That was my first attempt !!!! Not even close !!!! Lol :D

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Jules
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Re: PEI Bed Surface

Post by Jules » Tue May 26, 2015 8:19 pm

Okay, so no float and the sheet might not even be any good.

This does not look promising. :geek:

kazolar
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Joined: Wed May 13, 2015 4:39 pm

Re: PEI Bed Surface

Post by kazolar » Fri May 29, 2015 4:40 am

You can make a jig to help lineup the boro and a piece of PEI. Basically corners extended, and just lineup and drop the PEI onto the boro.

I tried Saisnsmart TPU today -- took a risk with a 20x20x10mm calibration block, bed heat turned off. Peeled off without any problems, stayed put during print. I know it's a small sample, but so far PEI has worked well for everything I've tried. I know it wears out so ordered 2 more sheets to have as backups.

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