TPU on PETG Supports not a good idea..  

RE: TPU on PETG Supports not a good idea..

Yes. These materials really like each other. Same with tpu and pla. However, this also means that you can use tpu as a hinge for things made with pla or PETG. Works great since tpu is sooo strong!

RE: TPU on PETG Supports not a good idea..

I managed a couple pretty decent TPU prints with PLA supports. The support interface used the default settings and the separation went just fine. Still sorting out the ideal TPU settings but that is a different issue. 

RE: TPU on PETG Supports not a good idea..

Can you post a picture of the support Settings here? Theese were 0.2 (detachable)? Did you use organic supports?

RE: TPU on PETG Supports not a good idea..

TPU + bvoh interfaces + PLA supports kind of works.  I'm still not thrilled with soluble profiles on the XL right now.   It's the main thing I wanted the XL for.   BVOH and aquasys 120, both suffer from a similar issue in that the first several mm of extrusion on the prime tower don't want to stick.  I think it has to do with the difference between docked temp and print temp.  I'm still experimenting, but I'm pretty disappointed that beta testing didn't discover this.   I almost feel like for these soluble materials you need a brush and bucket + gcode when the extruder comes off the dock and before it goes to prime tower to prime some material and then do a brush + retract before it goes to the prime tower,

RE: TPU on PETG Supports not a good idea..

This is what things were looking like with the bvoh interfaces and pla supports for tpu.  I'm currently printing off the nozzle brush stuff and hope that will help with the bvoh oozing.  I realized I had missed some painting some supports but still you get the idea.   I think once solve the bovh oozing problem this will work fine.  still need to drop a deg or two on the tpu but this

And separated supports removed.  Again, I needed to add some some additional painted supports etc.  and I've not reprinted since I did that.  The bvoh is currently drying and I might try this print again after I get the nozzle brush stuff set up.

Posted by: @acht

Can you post a picture of the support Settings here? Theese were 0.2 (detachable)? Did you use organic supports?

RE: TPU on PETG Supports not a good idea..

so I'm pretty unhappy with solubles right now.   I think both bvoh and aquasys exhibit roughly the same behavior,  for the first several mm on the prime tower  and on the model(more on the wipe tower though)  the soluble doesn't stick to the other filaments used.   after this it starts to stick, but at that point the damage is done.  I feel like it mostly has to do with the temp the filament is idled at, but maybe also the extrusion speed when it's first extruded after a tool change.   The MMU had a lot more options for controlling cooling moves, etc on the wipe tower, but not with the XL.  Anyway, I'm doing more experimentation of just using tpu + pla as the support material.   I really was hoping with the purchase of the XL to reliably do soluble interfaces but so far it's not been great.  Somehow I managed to get this print with the petg + aquasys 120 to work reasonably well the one time I printed it.  But, by no means have I found reliable settings that will work for PETG or TPU etc.  it's very trial and error.   I went back to using bvoh since there is at least a built in profile in prusa slicer for it, but it doesn't work that well.  I'm going to keep at it though.  Being multiple extruders, the XL should be able to do this.   On the bright side, this isn't a hardware problem and can probably be fixed with some software/firmware updates.

RE: TPU on PETG Supports not a good idea..

so just as a follow up.  using strictly pla as support and interface material for tpu seems to work.   It's going to depend greatly on what model you're printing, but this kind of works.  I'd rather have gotten this to to work with bvoh as an interface material but it's an option in a pinch.  I'm really hoping that solubles like bvoh and aquasys 120 end up being better supported.  I might give PVA a try, I have a roll of primaselect pva that I've not tried on the XL.   I'm currently drying the bvoh at 55C and I'm going do that for a day and give it another try just to rule that out.   bvoh gets pretty flexible at 55C 

RE: TPU on PETG Supports not a good idea..

I was able to print TPU with PLA supports. The supports detached very easily.

RE: TPU on PETG Supports not a good idea..

That looks really, really good. What was your interface offset between the TPU and the PLA? (and, sorry if I missed it, do you have a summary of what you did to get this working that well? Slicer settings, tool tweaks, etc.?)

RE: TPU on PETG Supports not a good idea..

So I never really thought through putting supports like that in just the openings. I would always think about from the build plate. That technique looks really good and I assume it would save time and filament. Thanks for the idea, I'll try it soon.