Problems with PEI

[nitewatchman]

I moved my printer to a PEI for a build surface 4 or 5 months ago to solve the problem I had with ABS lifting, warping and curling corners. It has worked very well without the mess of using Glue, Hair Spray or ABS Juice until recently.

Now I have a problem that is the reverse of my initial difficulty. My ABS parts are adhering to the PEI to the point that they cannot be removed without damage. PLA is still working as before and snaps right off. There has been a LOT of material across the plate and it is showing wear in the center. Additionally when parts are removed from the PEI, the surface that was in contact has a chalky appearance. I now run the plate at about 60-65C for PLA and 80-95C for ABS.

I routinely sand the surface (2000G Wet or Dry Paper) and wipe down with Acetone to remove any ABS residue and oils from fingers, etc. I have a second spare plate that I think I will now put in service but has anyone else experienced this.

The warpage control is great but can use the print if I can't get it off the bed intact.

[Holy1]

I have had a huge problem recently too with ABS welding itself to the PEI. I have had to flip the plate and go back to glue on glass for the prints that I cant get a good grip on to pry off. Often the the model tears off leaving the first layer still there.

PLA is still stable and comes off easily. I use the glossy side so I have never sanded it. I wonder if I could polish it?

[Nylocke]

Maybe try prying it off with a razor blade? Thats what I do with any of my larger prints that I dont want to risk breaking. Slide a razor blade under the part (I do it while hot, you may not want to (the blade gets toasty fast)) and get it as far as you can by hand. If the part is big enough you may need to slide a putty knife under the newly separated bit of the part to get it all off. I havent had any parts break with this method.

[nitewatchman]

I generally use a 1" very sharp Butt Chisel. Before I could just lever it slightly and the part would pop off. Now not so much.

[teoman]

Lowering the heat?

I am still having the opposite problem i am able to heat it to a max of 88 degrees. I am looking at upgrading the power supply and the associated wires.

So if you tried a lower temperature maybe you would not get such complete adhesion.

[critical_limit]

@Teoman:

My PEI Sheet is very good at a starting point of 95°C. At 100°C it is good and I have to wait to complete cooldown that the part will pop off. At 110°C and above my part is sticking like hell and I have to use a lot of force to get it loose.

So, if your heatbed is only going to 88°C, you will be suprised after upgrading to 24V......

[Fiddler2070]

I run at 110. When the print is finished, I wait till bed hits 100 and just pull the print off with my hands. Some stick harder than others but they all come off fine.

[nitewatchman]

Problem with PEI resolved itself last night. After returning home from work, I started to remove the day's print form the bed. Bed temperature was about 23C. When I levered up on the part the PEI in the center of the bed failed and broken out a section about 1-1/2" in diameter. Bummer.

I removed the rest of the PEI. Cleaned of the tape residue (what a chore) and mounted a fresh PEI sheet. Printed another part over night and it was tight but released cleanly from the bed without a lot of effort this morning.

This is just like color television. I don't understand how it works but I watch it anyway.

No idea what was wrong but a new one fixed it.

nitewatchman

[teoman]

4-5 months...

how many hours of printing did you get out of it? i.e when should we schedule a redo of PEI surface?

Initially in this thread it was considered as a wear item.


Ah man, seemecnc should really sell aluminum disk coated with PEI...

[nitewatchman]

Meter says about 35 days. Who knows if that is even close?

[bvandiepenbos]

I have noticed my PEI print surface adhesion with ABS changes with temperature.
90c is not reliable, 100c is good, 110c sticks like crazy. But I have not had prints damaged when removing. I use a fairly stiff 2" wide putty knife with edge ground to a sharp knife edge. Bed is usually cold, but sometimes 80-90c, either works.
Just pry print off and go again. nice!

I have only ever carefully scraped surface clean and occasionally wiped with alcohol or window cleaner.
Never have sanded it, I wonder if sanding could make it stick to much?

[Holy1]

Problem with PEI resolved itself last night. After returning home from work, I started to remove the day's print form the bed. Bed temperature was about 23C. When I levered up on the part the PEI in the center of the bed failed and broken out a section about 1-1/2" in diameter. Bummer.

I removed the rest of the PEI. Cleaned of the tape residue (what a chore) and mounted a fresh PEI sheet. Printed another part over night and it was tight but released cleanly from the bed without a lot of effort this morning.

This is just like color television. I don't understand how it works but I watch it anyway.

No idea what was wrong but a new one fixed it.

nitewatchman

Hmmm. Maybe it's time to replace mine then . I have been using it since Febuary. I tried again with abs on a small model at 80c. It broke at the first layer trying to remove it. If I print lower than 80 c then the edges curl. Go figure.

[nitewatchman]

similar to what I was seeing.

[teoman]

It was too good to be true.

But printing for 35 days for 20 usd worth of PEI is a pretty good deal most of us would gladly pay not to mess with glue, spray, tape, removing and washing the glass.
I think that i am at 1 day with the PEI. Once i get my power supply (tomorrow) i should go a lot quicker.

[Nylocke]

My wondering is how is Michael's PEI holding up? He was one of the first of us to start using it. Has he had any issues with his (I'm betting he has around 1000+ hours of printing on it) ?

[teoman]

That would make 42 days worth of printing.

[Eaglezsoar]

I doubt if Michael has had any problems with his PEI, he would have said something.

[nitewatchman]

It was too good to be true.

But printing for 35 days for 20 usd worth of PEI is a pretty good deal most of us would gladly pay not to mess with glue, spray, tape, removing and washing the glass.
I think that i am at 1 day with the PEI. Once i get my power supply (tomorrow) i should go a lot quicker.

Not complaining! I totally agree the cost per time and not having to deal with tapes and sprays and glues.

Ordered two more sheets from McMaster-Carr last night.

[nitewatchman]

I doubt if Michael has had any problems with his PEI, he would have said something.

I suspect that mine was somehow damaged in my handling of it. The center was starting to show noticeable wear and roughness and every print coming off was pulling a white residue with it, like the surface was chalking away. Maybe this piece was just the "runt of the litter". Additionally almost all of the printing was done with ABS at 100C to 105C. After the sticking became too good, I backed down to 85C to 95C but all that did was increase the tendency of the corners to curl.

At any rate, don't take my whining the wrong way. I am sold on the idea and a confirmed fan of the method.

PEI IS THE WAY TO GO.

[Generic Default]

I just ran into a new problem. My glass cracked (it's actually a mirror). The glass costs $6, the 468 tape costs around $5 but the PEI costs $18.

Does anyone know how I can get the glass and double sided adhesive off of the PEI without destroying it? It would be much easier to re-tape to a new mirror than buying and cutting new PEI.

[nitewatchman]

When I changed my PEI sheet, I was able to lift it on the edge and slowly peel it off by pulling it up from the lifted edge, it came off in one piece. Of course I was trying to save the glass.

Most of the tape stayed on the glass and was difficult to remove. Of course that is not your problem since your glass is broken. To remove the tape I washed quite a bit off with acetone and a lot of elbow grease (wax on - wax off type duty). There was some very stubborn residue left and I attacked it with a scrubbing sponge and dishwashing soap. This seemed to remove it better than the acetone.

nitewatchman

[Eaglezsoar]

When I changed my PEI sheet, I was able to lift it on the edge and slowly peel it off by pulling it up from the lifted edge, it came off in one piece. Of course I was trying to save the glass.

Most of the tape stayed on the glass and was difficult to remove. Of course that is not your problem since your glass is broken. To remove the tape I washed quite a bit off with acetone and a lot of elbow grease (wax on - wax off type duty). There was some very stubborn residue left and I attacked it with a scrubbing sponge and dishwashing soap. This seemed to remove it better than the acetone.

nitewatchman

I haven't tried it but I wonder how a single edge razor blade in an appropriate holder would have done?

[teoman]

What if you just put it in a dishwasher?

[Eaglezsoar]

What if you just put it in a dishwasher?

The dishwasher you mentioned might be a good idea. Who is going to be the first to test it?

[nitewatchman]

When I changed my PEI sheet, I was able to lift it on the edge and slowly peel it off by pulling it up from the lifted edge, it came off in one piece. Of course I was trying to save the glass.

Most of the tape stayed on the glass and was difficult to remove. Of course that is not your problem since your glass is broken. To remove the tape I washed quite a bit off with acetone and a lot of elbow grease (wax on - wax off type duty). There was some very stubborn residue left and I attacked it with a scrubbing sponge and dishwashing soap. This seemed to remove it better than the acetone.

nitewatchman

I haven't tried it but I wonder how a single edge razor blade in an appropriate holder would have done?

Not well at all, turns into a ball of gum. Guess how I may know this?