Hi all,
I’m using Sunlu High Speed Matte PETG. Everything was fine with the supports and then this started happening on the first layer after the supports. Does anyone know what this and why it might be happening? Any advice would be welcome….
Hi,
So, what’s under the main body of that piece? I only see some starts of supports around the edges (I think that’s what they are). It looks like most of that piece is extruding over thin air… ?
And no idea what’s going on with the back half… is it supposed to have a fine grid like that, or whatever that is? Or is that part of the issue?
You’ll need/want to provide more information to get any proper advice.
Cheers,
-Max
So I’m making a magnetic printing jig for a flatbed UV printer. That is layer 22 of 101
There is a lip that runs along the bottom and right hand side only that’s 3mm. The lip hooks onto the bottom right hand corner of the print bed.
As a result of that 3mm lip that runs along the bottom and right side, it’s filled the whole bottom with supports. So that is all support that’s supposed to be sat under the body of what will be the jig. Because the top side is the side where I will place objects, flipping it would reduce the amount of support required but not by much.
Not really sure how that matters as I thought the whole point of support was so it wasn’t printing into thin air? So surely the mesh is enough as it’s printed on plenty supports before?
Its not clear what the goal is from that pic, can you share the 3mf and/or screenshots of the slicer of the intended object?
1 Like
I couldnt put the 3mf here so ive saved it to my google drive for you.
I hope this helps.
For more context, I think that is layer 23. So everything was fine and Layer 23 was a complete flop. It could be Z offset? PETG prefers less bed squish than PLA. My PLA works perfectly, so do you think PETG potentially needs a Z offset?
Ah, it’s so much clearer to look at the actual model.
Yea… that’s a doozy… that whole large area suspended just for a few protrusions at the (current) bottom. You say that prints “perfectly” with PLA? Just as configured here? And the supports come off? Not doubting, just surprised/impressed it would work.
My guess offhand is that the .2mm Z distance between the support interface and the first large layer of filament (where you say it fails) is just too great to make a decent first layer for that large flat area. Maybe the PLA is better tuned or something… but that’s a lot of area to bridge, essentially.
Oh and the eternal question… is it dry? PETG has to be dried. And some more.
I’d want to print something like that with a separate (non-sticking) support filament and zero top Z an a fine interface spacing (maybe 100%). Like using the PLA as support for the PETG.
Also I’d probably flip it over because that side looks simpler to support and remove (smaller large areas and fewer small noooks).
HTH,
-Max
whew, a sea of support
and the one layer above this pictured takes over 1 hour while the rest are generally 5mins ish. So there’s some minor cooling time differentials.
I think you’ll have better luck tuning the support like this:
A smidgen less gap for good luck, and if you put the top interface spacing at 0 - it tightens up that mesh that the huge overhang has to lay on.
I dont run HS PETG so I cant really give much advice on the filament but I would try to do a very small overhang test and/or temp tower, and try to get your bridges as good as you can.
The sheer amount of flat overhang here also might be interesting to experiment with a different support material and 0 gap.
Are you using a 0.6 nozzle? PETG is not the filament for printing quickly so I would slow it down. Make sure that your infill is high enough, and your flow ratio is correct and calibrated.