powder coated PEI steel sheet - less sticky than PEI sticker build plate  

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

Posted by: rmm200

[...] Any chance any of the really bad sheets come from a supplier other than Prusa? It would be a ripe product for a knock-off.

I ordered mine as part of my original Mk3 order in Jan 2018. I dealt directly with Prusa for all transactions, including completing the survey selecting the textured sheet and waiting over 14 months for it. I think it would be highly unlikely any sort of swap occurred. I suspect there are just variances in each batch. Some may be great, others -- may be the end of the run -- seem to suffer inconsistencies.

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

I got my PC sheet with my new printer.

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

I ordered mine a couple of months ago, after they were generally available. And I suffer the same issues when printing PLA. Not sure if it's a particular batch, or just the way it is with powder coated sheets.

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

Mine is labeled also BH-25.
I don't see any coloration difference.
Yesterday I turned the sheet and now I'm printing on the other side. So far, is better than the other side. PLA sticks slightly better.

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

Hello everyone. I made some progress on this matter and now I'm printing pla without warping at all.
On my others (non prusa) printers I have a flexible steel sheet with PEI on some, and buildtak on others.
From time to time the PEI become less adherent and the IPA is not able to recover it. In my country acetone is a controled chemical, you can't buy it and is not an option.
So, in those cases, what I do is take a sandpaper with fine grane, like 3000 or more, and (very, very) gently pass it on the PEI surface.
After that I clean the surface with IPA as usual and it is ready to print like new.
I did this on the less sticky side of my PCS and now, it works perfectly.
I have been printing pla with very low contact area and it stick well until the sheet cools down. Then the prints just release themselves from the sheet as expected.
I know it sound a little bit dramatic, but It works on the first try and have been working for my on the others sheets for years.
Hope to help somebody.

I forgot to add. Now I printing with Bed at 60c and tool 215c. There is no need to overheat the bed like before.

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

So - maybe - Scotch Guard is not as dangerous as it sounds.

I wish Prusa would do a little research and see if they should be abrading PC sheets before shipping them out.

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

Posted by: rmm200

So - maybe - Scotch Guard is not as dangerous as it sounds.

I assume you mean the Scotch-Brite pads, not the waterproofing spray. The pads vary in abrasiveness, so verify which Scotch-Brite pad before using. I use the 7445 (least abrasive) pads on my smooth PEI sheets, but only infrequently. Other types are as abrasive as coarse sandpaper. 

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

Posted by: rmm200

So - maybe - Scotch Guard is not as dangerous as it sounds.

I wish Prusa would do a little research and see if they should be abrading PC sheets before shipping them out.

If 3000 or finer grit sandpaper is required, I don't think there is any Scotch-Brite pad I'd use.  But I suppose you could be gentle.

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

I use 3000 because is easy to find. Sometimes use finer. Is very important be gentle, very gentle with the sheet. Don't make force against the sandpaper and the sheet.
I don't know how many print it will last until I have to do it again. I do it on my others PEI Sheet like twice a year.

I printed these today. 

and this extruder rotation with a very small contact area. 

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

Hi,

I've the same problem with my new pei powder sheet, low adhesion with pla and petg , very disappointed.

I wish to ask to the community which is the difference of z heigth you find using the powder pei instead the pei sheet, just to be sure I lowered the nozzle enough.

Regards

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

Posted by: stefano.p2

I've the same problem with my new pei powder sheet, low adhesion with pla and petg , very disappointed.

I wish to ask to the community which is the difference of z heigth you find using the powder pei instead the pei sheet, just to be sure I lowered the nozzle enough.

Search for Jeff Jordan's "Life Adjust" thread and use that procedure to calibrate your Live-Z. It's much easier to use and understand than the on-board Live-Z routine.

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

Here's Jeff Jordan's "Life Adjust" thread.

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

Thanks for the advice. This is the procedure I usually follow. For me the first layer is correctly configured, but I red a lot of post talking to squish the first layer to have more adhesion, and  l'm try to understand if I'm doing something wrong or the bed don't work  as I expected ( or don't work at all) 

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

first layer squish is a thing for non-heated bed machines - the mk3 should not need it

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

Posted by: david.a66

first layer squish is a thing for non-heated bed machines - the mk3 should not need it

So sayeth Prusa...

The aim is to continue decreasing the value until the extruded plastic is sticking nicely to the heated bed. Extruded plastic should be slightly squished. 

Or as I like to put it, you sure as hell don't want cylindrical extrusions if you want adhesion!

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

Also on video.

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

Hello everyone.

Just want to update, have been 4 weeks and I'm still printing without any problems after the sweet sanding treatment.. 

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

I never argue with success. That is a thing of beauty.

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

Posted by: @stefano-p2

Thanks for the advice. This is the procedure I usually follow. For me the first layer is correctly configured, but I red a lot of post talking to squish the first layer to have more adhesion, and  l'm try to understand if I'm doing something wrong or the bed don't work  as I expected ( or don't work at all) 

Just to update , I lowered a the z axis more than I usually did with the other bed and more than I thought was the correct layer and now I have good adhesion , at least with petg. 

I usually lower the z axis until I have a good layer , now I followed another guide that tell to lower the z axis until the nozzle start to interfere with the layer and then raise a little bit until the nozzle  stop to leave sign on the layer ( a sort of maximum squeeze ) ( sorry for the explanation, but it's difficult for my level of english 🙂 ).

RE: powder coated PEI steel sheet - less sticky than PEI sticker build plate

For adjusting Z, it is hard to beat:

https://forum.prusa3d.com/forum/original-prusa-i3-mk3s-mk3-assembly-and-first-prints-troubleshooting/life-adjust-z-my-way/