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3D-Print wrote:Awesome thread!

I wanted to make sure I'm pulling this all together correctly. In summary, adding PEI is as follows... Correct?

PEI from amazon is: PEI (Polyetherimide) Sheet, Opaque Natural, Standard Tolerance, ASTM D5205 PEI0113, 0.03" Thickness, 12" Width, 12" Length

1) Triple-washed the glass, after scraping it down with a razor blade, a cleaner, then Windex, then isopropyl alcohol
2) Place the 3M tape
a. TapeCase 468MP
b. TapeCase 468MP 12in X 12in
3) Isopropyl EtoH clean the PEI, let it dry, then laid it down with a minimum of curling of the plastic.
4) Weight it down

Is that correct?

Thanks,

Dan

I do this a little differently.

After doing the cleanliness next to Godliness thing, I apply the tape to the PEI first.

I pull the first inch of the cover sheet loose from the first side of the tape and carefully fold it back. This leaves an inch of sticky exposed across the full width of the tape (1"x12"). I position this carefully on the PEI sheet and stick it down. I then lift the free end of the tape sheet, grab the folded over cover sheet and start peeling it off while sticking the tape down to the PEI. This allows you to work the sticky edge down progressively and not get big bubbles or wrinkles. If the tape ever touches itself just get another piece because things will not improve with effort. After making it all the way across, I have a sheet of PEI with the tape on one side. Decided what side you want up before you start this drill, VERY IMPORTANT.

I repeat the operation to attach the PEI/Tape assemble to the glass. Again folding back about an inch of the second side cover sheet and I carefully align the PEI to the glass without letting the sticky touch. When it is in position push the sticky edge down and squeegee the tape down for the full inch width. Now the PEI can be flexed up off of the glass and the cover sheet again pulled from between the PEI and the glass by tugging on the loose end of the folded over cover sheet. Again work the PEI down onto the glass as the cover sheet is peeled to minimize bubbles. After making it all the way across you should have a tightly stuck PEI sheet with no large bubbles (lots of tiny ones) and NO TAPE WRINKLES.

I then lay the PEI/tape/glass sandwich PEI side down on a towel and using a sharp machinist scribe, score around the PEI using the glass edge as a guide. I really bear down on this and score about half way through (takes several passes), then break the corners off by flexing the PEI away from the glass side. Any sharp corners, edges or rough spots are cleaned up using a file. The plate is now ready to go, no cure time, weighting down time - just clip it, heat it, print it.

I have done four glass plates so far and used five tape sheets. It is really not as bad as it sounds and takes less time to do than it took me to type this diatribe.

Good Luck! The results are worth the effort.

I took this photo a few minutes ago for a gent on another thread. But I realized you can see the PEI surface quite clearly (click the photo to see the high res version).

Thanks for the tips on how to place the tape, PEI and glass. That was nice and clear and makes sense. Will let you know how it goes.

Love all the pics and help. Is great to benefit from all your efforts (year long). Much appreciated.

Dan

techstorage wrote:I am running out of glue sticks, so time to install this update.

I have a thin copper sheet .032", ULTEM PEI sheet .003" and 3m tape to make the sandwich on my Max v2 with an extra glass plate I purchased from Seemecnc.
...

I installed the PEI on my Glass Plate and added the copper plate. Installed my E3Dv6 and re-calibrated the printer. The PEI print bed surface is great!

After reading mhachney's other post about starting on the first layer over and over till you get it right, it is very helpful, also. I can take up the first or first and 1/2 the second layers to see how things are going and I don't have to reapply glue or ABS Juice.

I just ordered an aluminum sheet to put under my glass. I got one that's painted on one side, that can go down for insulation from the heater but would look better up. Maybe I'll just Kapton the bottom of it.

I threw my sheet of aluminum directly on the bed. Didn't really think about it at the time but I haven't had any issues.

so i cut a small piece and put it on my flashforge creator pro and its sticking great... now to test a large print

How do you clamp down the aluminium, glass pei combo to the onyx.

On my last few prints it has shifted rather badly...

I use the industry standard 3-D Certified Paper Clips (5).

The ones that came with my kit dont fit anymore.

So i attached my piece today, with 3m sticky (which is awesome, perfect)... but my first long print and visually (its still going) at least one corner is still peeling up...
230 c
100c bed.
lightly sanded the rough side.

should i run the bed at 110? maybe so.

ABS I presume? Before ramping up the temp, make sure the PEI is COMPLETELY degreased and clean. I suspect they use some sort of release agent when they manufacture PEI and that seems to cause initial problems until the stuff is thoroughly clean. Also make sure your 1st layer thickness and calibration are good. PEI is not a silver bullet for improper machine setup.

Yes ABS... I used a .2 first layer thickness, so perhaps that could be fixed by a .35 or something first layer.
calibration is tight.. very good... .
I do like the stuff... seems easy to use and quick nice. just hoping i can get it working 100%

so i just aborted a print (for other reasons) and tried to peel the first 3-4 layers off the bed and it was REALLY hard...
so here is what i inadvertently ended up doing.

1. Alcohol rubdown
2. ABS glue (too thick)
3. Scrape ABS glue off.
4. Acetone and scrape til it was clear.
5. Alcohol rundown.
6. Light sand.


Seems to be working. ill let you know in the morning after i kick off this last big print.

PEI Is in place, I purchased from McMaster Carr the 12x24 sheet and it is thin. The z adjustment made a small dimple and there is an air bubble by an edge. I looked at the order form and it is .003" not the .03" on Amazon.

Prints stay down well, but I don't know how long the thin sheet will last. Ordered the .03" on Amazon with more tape to be ready for replacement when needed.

You should always have a sheet of paper under the nozzle when adjusting Z with the hotend hot. PEI WILL melt and dimple if you are not careful. My first piece of PEI had 100s of Z adjustments done with it and no dimples, you just need to go slow and use paper and don't ram the nozzle into the PEI.

You might be able to sand the dimple out - or at least any raised edges around it. Once you have some experience on the PEI, remove it and flip it over to get a fresh surface. I recently did that without needing to retake. With the thinner material, it would be a lot easier.

The thickness of the sheet has NO EFFECT on its longevity. If you are scraping, melting and/or gouging a .003" thick sheet, you will do the same to a .03" thick sheet. I'd actually prefer the .003" and will use that the next print surface I make. It will transfer heat faster.

Dugginhawk, not sure why you put ABS glue on the PEI? In any event, it probably had the effect, along with the acetone rinse, of thoroughly cleaning the surface.

i did it because im still having major curling.. even after ALL of those steps, im curling...
I even did a brim this last print and there was just enough gap between the plastic brim and the print and it curled up...
im running 110c on my print bed... im so frustrated

any chance 110 for the bed is just too hot? should i back it down to 90 ?

I have to ask... Did you or are you running canola oil in your Bowden tube? You really should not have any issues printing ABS or PLA on good, can PEI. It really sounds like you have a contamination problem - ESPECIALLY if you abraded the PEI with some very fine sandpaper.

BTW, where are you located? Are you one of the guys up here in NE?

It is possible that too hot could be a contributor. I print ABS at about 80-85°C on PEI.

I also have to ask...

Are you using a fan? If so, when do you turn it on? Did the part start to curl before the fan came on? Are you running the fan at low speed for low airflow? Maybe take a look at strategy #12 in my guide (See signature).

No canola. No fan. No contamination.. pretty controlled environment.
I am actually In Des MOines IA, but work in Omaha, Lincoln weekly. (traveling IT sales).
Are you in omaha? next time im over that way id love to meet for a coffee or something.

No, I'm in Boston, MA - I thought you were from the NE.

Ok, that is just plain odd! We need to identify the variables. The 0.003" PEI is one. Can you send a link to where you got it? Perhaps it is a co-polymer or something and not the same material the rest of us are using.

Have you been able to print this part on other surfaces without curling? Did you post a photo or STL of the part?

This is the one i bought

http://www.amazonsupply.com/dp/B0013HKZTA

No. i havent been able to get it not to curl with anything ive tried. glass with hair spray, glue stick, glue stick liquid.

I cant share the STL file because its a customers. it is about 8x4x1.5 in inches... 20-25 infill,

Sorry duginhawk, I confused you with techstorage for a minute (he has the 0.003" PEI) - you have the same material the rest of us have used. Do you have shiny side up or matte side up?

Can you describe the print process...

does the first layer go down nicely and stay put when the 2nd and 3rd layers are printed?

At what point does the part curl?

Does it curl in the same place all the time?

Have you tried rotating the part in the slicer to see if the part peals at the same spot on the part or the same spot on the PEI?

Have you shifted the part along X or Y to move it off center to print at a different spot on the PEI?