PLA on Textured
This is only to demonstrate that PLA really does print well on a textured sheet.
This is a Raspberry Pi 4 case with Buck converter (Thingiverse) printed in Prusa Black PLA.
Note the square openings - no supports - and no stringing. Always seems like magic to me.
OK - I used a brim. I am super cautious...
RE: PLA on Textured
[...] OK - I used a brim. I am super cautious...
You can make stuff print on the textured sheet. It's just that some of the sheets have far worse adhesion with PLA than others. The fact that you pulled off a print (using a brim no less) changes nothing.
RE: PLA on Textured
PLA will print on textured, but I find, that it ends up leaving a microscopic layer behind on the textured PEI which makes adhesion a problem for subsequent prints. It is possible to get rid of this coating, but getting it out of all the nooks and crannies on some textured sheets is almost impossible. Larger prints can be more problematic especially with curling.
Other stickier materials like PETG work better because they are so sticky, they stay stuck to themselves, so when removed, then all the PETG comes off leaving a clean surface with nothing required except an alcohol wipe, no need for washing or anything stronger.
I found printing a single layer PETG print over a previous PLA print, would manage to remove most of the PLA residue from the textured PEI.
I nowadays have one textured sheet which I keep just for PETG, it always sticks quite well and never needs any glue, washing scrubbing or any further work except a misting with IPA and wipe with a clean paper towel, and often I don't even bother to give it an IPA clean between prints if the parts are smaller than 1/4 the build plate, and have never had a PETG print come away fully. I only had prints come away back in the early days of my ownership when I did not know any better and mixed PLA and PETG prints on the textured surface, but I still have never washed this textured sheet or scrubbed it or used acetone and still have PETG prints stick and pop off cleanly when cold. It just works.
I would not say the adhesion is exceptional because for larger prints I have to watch draughts, as this can cause localised cooling which can result in edges curling up with PETG, but this rarely happens, but can catch me out as well. I try to print PETG with a bed temperature of 90 Deg, but would not even bother to try to continue to print after a power cut because if the bed temperature drops to below 65, the PETG part will have already popped off. You can hear it detaching without having to do any flexing of the bed, just leave it to cool slightly, if I'm in a hurry, I just take the still hot steel sheet off the printer and place it on the table, the print just pops off within a minute.
For PLA I have a smooth PEI sheet which works well and cleans easily, again using nothing more than IPA and a wipe, but I don't print much in PLA. I guess it works better because there are no nooks and crannies to trap material.
Normal people believe that if it ain’t broke, don’t fix it. Engineers believe that if it ain’t broke, it doesn’t have enough features yet.
RE: PLA on Textured
[...] OK - I used a brim. I am super cautious...
You can make stuff print on the textured sheet. It's just that some of the sheets have far worse adhesion with PLA than others. The fact that you pulled off a print (using a brim no less) changes nothing.
I find it hard to believe that there are textured sheets out there worse than mine. PLA would simply not stick. I spent two weeks fighting with it before I broke down and ordered a smooth sheet from Prusa. About the time that arrived - I discovered Dawn detergent, vigorous scrubbing, and fresh paper towel drying. That made me a believer. Now I choose the sheet for PLA based on the surface texture I want, which is as it should be. For this box a textured surface was the right choice.
RE: PLA on Textured
I find it hard to believe that there are textured sheets out there worse than mine. PLA would simply not stick. I spent two weeks fighting with it before I broke down and ordered a smooth sheet from Prusa. About the time that arrived - I discovered Dawn detergent, vigorous scrubbing, and fresh paper towel drying. That made me a believer. Now I choose the sheet for PLA based on the surface texture I want, which is as it should be. For this box a textured surface was the right choice.
I have no way of saying whether mine is better or worse, but I spent a lot of time trying to get it to work using Prusa's instructions. I finally gave it a dunk under hot water with an intense scrub with Dawn. This seems to have removed some manufacturing residue and improved adhesion slightly. Knowing that Prusa's warranty is non-existent on these things, I decided to treat it like my other PEI surfaces and gave it a deep wash with acetone to remove any oxidation or other crud, followed by another wash with Dawn. It improved. It's "OK" now, but nowhere near as reliable as the smooth sheet. I find every print a bit of a gamble.
This wouldn't bother me so much except Prusa's otherwise-excellent customer support has really gone AWOL on this. They're clearly aware of the issue as they have made ninja edits to their cleaning instructions, even going so far as to note that the sheet is not good for small PLA parts in the manual. All done without notifying those of us who purchased the PC sheet previously. They know something is amiss, but aren't talking about it. Almost like the corporate lawyers have taken over. In my mind, this is a dip in Prusa's historical level of integrity. The product page for these sheets now states (after I purchased mine):
Consumable parts, such as PEI sheets (smooth, textured, etc.) are not covered by warranty as the coatings are designed to diminish over time unless failure has occurred due to a defect in materials or workmanship. Cosmetic damage, including but not limited to scratches, dents, cracks or other cosmetic damage is also not covered by the warranty. Only defective sheets on arrival are covered by warranty.
Lawyers at work. In my mind, a sheet that won't adhere is a defective sheet, but support claims different. I do wish somebody in the EU would take Prusa to task for this as their consumer protection laws tend to frown on this sort of dishonesty.
RE: PLA on Textured
Yeah - this is one of my grievances against Prusa - I received a PEI sheet with my printer that appeared to have been used as an abrasion test subject. One side had gouges, scratches, and other "more than cosmetic" damage. The one usable side has scratches too, but in places that didn't affect every printed part. To this day I've never used the back side of that original sheet.
When I contacted support, before I had even built the kit, they were like "So, what do you want us to do about it?" Their tone was rather condescending, and were implying I had damaged the sheet removing it from the bubble wrap.
Makes me wonder why I spend so much time doing their Tech Support, for free.
RE: PLA on Textured
So I started on a powder coated sheet and got a couple of other aftermarket versions and Prusa versions of the powder coated sheets before finally getting a PEI sheet. I have printed all kinds of PLA stuff on the powder coated sheets and without any unusual issues, but you do have to watch out for drafts and lifting. Getting the sheet clean is important as is a good Live Z.
I guess it was a case of "you don't know what you don't know" or what, but yeah the Prusa PEI sheet is the bomb when it comes to PLA. It sticks like no other and is very easy to get it to work compared to the powder coated version. I tend to use the PEI for new prints I am doing in PLA because I have had zero issues with adhesion with that thing. I am a bit scared to try PETG on it, so it is PLA only for me and I do have plenty of PC sheets for PETG and other filaments.
Strange women, laying in ponds, distributing swords, is hardly a basis for a system of governance!
RE: PLA on Textured
Ditto, I've been using my PC sheet for everything as of late. No issues with PLA or PETG, both stick like there's no tomorrow until cooled down.
RE: PLA on Textured
@robert-rmm200
Great reply!
I've learned a lot about 3d printing and the MK3, and solved some tough (to me) problems by reading these forum discussions. The advice from all you experienced folks is very valuable and much appreciated by those of us who are still learning!