Tips on better first layer adhesion specifically on the XL?
I've got the 2 head XL and overall things are going pretty well. One thing I haven't been able to sort out though is why I'm not getting expected bed adhesion like I do with my Prusa MK3s and Vorons. I keep getting corner lifting on parts I've never had a problem with on the MK3s. On the MK3s, I use a quick circular swipe of purple glue stick which I rub in with 99% IPA. It's a solution that's worked for years where even lifting on challenging parts is extremely rare. MK3s are arguably the best for adhesion. On my Vorons I'll occasionally get lifting. On the XL though it's often. I'm using same bed temps (verified with an IR gun) though I have tried hotter with similar results. I've cleaned the build plate with soap/water, wiped with acetone and then applied my glue + alcohol method. Doesn't seem to work as well. Using (a lot) more glue seems to help but still getting corner lifting.
I don't think the corners are particularly challenging either. They're rounded (I've even increased the fillet on these parts more than I was I using on my MK3s). I did notice using a combination of PLA as a base followed by a TPU top (I'm using that as a sort of anti-slip mat for the part) seems to increase the change of corner lifting though I get it in straight PLA parts too.
First layers look good to me, though one of the things I was pondering is lowering the first layer height. I can't figure out where that setting might be and only recall hearing mention of that in the original announcement video for the XL?
Any thoughts would be much appreciated!
RE: Tips on better first layer adhesion specifically on the XL?
I've had the same with rPLA using input shaper (IS). Turned out the was no IS profile for rPLA, so the nozzle temps were way to low.
I've also had no luck with PVA, but I think the discount eSun roll need a month drying in the Sahara.
RE: Tips on better first layer adhesion specifically on the XL?
For the bed temps at least I've tried a pretty wide range, settling on around 62C as that's what my MK3's seem to end up being. On my Vorons I go a bit hotter (closer to 70C). All measured with the same IR temp gun. Seems like on the XL the corner lifting happens at low or higher temps. Good point on IS. I'm using the non-IS profiles at present. The first layer in particular I print rather slowly (10-15mm/s) to help with the lifting and to make sure I get a good first layer since the most functional part of these parts is the side facing the bed.
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I have the 5 head. I was having some 1st layer adhesion issues as well. Researching it I found lots of comments regarding cleaning your steel sheet with hot soapy water to resolve sticking issues. Ive been doing this every few rounds of printing and have had no issues since. I would have never thought that would be the fix because I always clean the build sheet with IPA between every single print run as well. Also dont touch the build sheet with your hands and fingers, even if you think you hands are clean there is always oil from you skin.
RE: Tips on better first layer adhesion specifically on the XL?
Yep that's the first thing I do with a new sheet. Usually a few times. Once I find it's been "seasoned" I haven't had to do that after. One thing I didn't think about though is a wash and then an application of acetone. I generally haven't had to do that to MK3 sheets in a long while but I've had to do that with some of my Voron build plates. So I may try that to see if that improves things.
It still does feel like there's something different from my MK3 sheets/setup vs the XL and I haven't figured out what it is. The times I've had bed lifting on my MK3s in the past several years I can probably count on one hand.
RE: Tips on better first layer adhesion specifically on the XL?
I've had the exact opposite problem, the prints stick too good on mine. I've been raising the Live Z sometimes if it's a large print. I have to use a razor sometimes to get the prints off, particularly on thinner flexible parts.
While the first layer is printing if you push and hold the knob it'll bring up live Z adjustment. The change you make is not permanent though. It resets every print.
You didn't mention but which sheet are you using? I've had the best luck with the PEI sheet for PLA and the Satin for PETG and TPU
RE: Tips on better first layer adhesion specifically on the XL?
I'm using smooth PEI with PLA yep.
Live Z for the XL? If so can you let me know where that setting is and if it persists? That is one thing I'm wondering might be the cause - that the default Z height on the XL is higher than I set on my MK3s and Vorons and that is impacting adhesion. I just did a print today after doing the soap/water scrub and acetone wipe noted above (followed by purple glue stick and alcohol right before I started the print). With all that I still had minor lifting on 2 of the corners. It's not much but on my MK3's it's none.
My next thought was to try 1000 grit sandpaper. I have done that one my Voron PEI sheets and it did work rather well so I'm hoping that might help without impacting the finish too much. Part of the reason I like the smooth PEI is my applications related to film photography where the first layer is often touching film.
RE: Tips on better first layer adhesion specifically on the XL?
I'm using smooth PEI with PLA yep.
Live Z for the XL? If so can you let me know where that setting is and if it persists? That is one thing I'm wondering might be the cause - that the default Z height on the XL is higher than I set on my MK3s and Vorons and that is impacting adhesion. I just did a print today after doing the soap/water scrub and acetone wipe noted above (followed by purple glue stick and alcohol right before I started the print). With all that I still had minor lifting on 2 of the corners. It's not much but on my MK3's it's none.
My next thought was to try 1000 grit sandpaper. I have done that one my Voron PEI sheets and it did work rather well so I'm hoping that might help without impacting the finish too much. Part of the reason I like the smooth PEI is my applications related to film photography where the first layer is often touching film.
See my post above for the live Z.
RE: Tips on better first layer adhesion specifically on the XL?
Oh thanks! Don't know how I missed that but yep that answered my Q! A shame it doesn't save the setting.