Nothing sticks.... to PEI!

[Cyber Akuma]

I have a Wanhao Duplicator I3, spent months performing modifications and improvements to it, one of the big ones being putting glass and PEI on the build plate. Everyone went on and on about how PEI is some wonder-material.... though I hear that while I was working on it something called Print Bite came out that's better but anyway...

So I finally used it for the first time yesterday.... and the only thing I have been able to successfully print are 20mm cubes.

I am using hatchbox PLA, not exactly an advanced or difficult material to print with, and from my understanding PLA doesn't even really require a heated bed, but I set mine to 45C anyway. I also reduced my acceleration to 800 and jerk to 3 as many people recommended to reduce ringing, and print at a fairly conservative speed of 50, with 45 for the outer/inner shell and 60 for the infill.

The Printer came with a OK-hand model used to test that the printer is working, and it never gets more than about 25 to 50% complete before it comes off the bed, and I even tried printing a 7 inch turntable.... basically a flat circle that takes up nearly the entire build plate... and not even THAT had enough surface area to stick to the PEI. I kept checking on it every few minutes and it was going fine... then I come back an hour later and it had completely come off the bed and was lying on the table.

Any suggestions what could be going wrong?

[ssayer]

For PLA, I use Elmer's Purple Glue Stick on glass @ 60°c and never have a problem. It sticks like mad until the bed cools down, and comes off as soon as the bed has cooled off. So... my suggestion? If you're only set up for PEI, put the Glue Stick on it for PLA...

[adrianq]

That is surprising. I too am using PEI with Hatchbox (black & red) and PEI has been a miracle surface for me. My set up is as follows:
- Maghold aluminum Build plate. This shouldn't matter, just needs to be flat. I usually have it set to 60c
- PEI with 3M adhesive attached to build plate
- Hatchbox PLA. I use 190-200 to print.

I will say that you should make sure you are properly trammed, but it sounds like you are if you are successfully printing 20mm cubes.

Have you tried upping your bed temp a bit? I haven't had luck with anything lower than 50c on my CTC printer.

On a side note, I would love to try printbite. I currently can't justify it since my PEI is working so well, but it really sounds awesome from all the reviews.

[curious aardvark]

best results i got with pei was when i coated it with pva gluestick :-)

It sort of works by itself, but i found it unreliable.

Printbite is amazing for pla. Thoroughlt recomnended.
See my printbite thread for results with other materials.

[adrianq]

C.A.,

How is your Printbite holding up? Are you still using the same one?

My PEI has been very reliable, but Printbite looks very interesting.

best results i got with pei was when i coated it with pva gluestick :-)

It sort of works by itself, but i found it unreliable.

Printbite is amazing for pla. Thoroughlt recomnended.
See my printbite thread for results with other materials.

[dunginhawk]

You dont need gluestick on pei, at all...
1. Make sure you sand it down with 1500 grit sandpaper (every 20 prints or so). keeps it working well.
2. Use IPA to clean it off once in a while due to finger prints etc.

[curious aardvark]

You dont need gluestick on pei, at all...
1. Make sure you sand it down with 1500 grit sandpaper (every 20 prints or so). keeps it working well.
2. Use IPA to clean it off once in a while due to finger prints etc.

Glue stick is quicker and easier :-)

The printbite is pretty much a lifetime investment.

the sheet is 1mm thick and very rigid and extremely hard.

Given the hasssle I had getting flexismart off it and the hitting with hammers and smalller sheet of printbite to remove the mini-gears. It's still completely unmarked.
Some judicious fine tuning in the calibration got that down to a very light tap.

A project I've added to my list is to copy the magnet and thin steel sheet approach used by geckotek.

Simply because it'd cool down a lot quicker and largeish pla parts do not come unstuck from printbite untill it drops below 29c.
If I had two swappable plates, I could carry on printing a lot quicker rather than sit there playing with the infra red thermometer gun :-)

But the durability of printbite is pretty damn good. I honestly don't think it'll ever need replacing.

In normal use there is no physical wear and tear.

Just be careful what make of tpu you use :-)