Is there a temperature adjustment or something you could put in a filament dyer/oiler that would cause PETG to more easily delaminate to help in the removal of support material? Can you do specific support material settings to make PETG used as support material separate from PETG? It seems like there is little in the way of filaments (PETG, nylon and some ABS mainly) in the 250C temperature range, so as opposed to looking for separate filaments, I am asking about PETG only solutions with no other filament used. Besides, someone asked about two filaments to use already in a separate thread so I would prefer those answers to go on his thread.
I won’t be much help I’m afraid but here are my thoughts based on information I’ve picked up.
As far as PETG on PETG goes it seems to stick to itself really well. The only way it does not stick to itself well is when it is printed too cold. Is that your experience as well? Not sure the temperature difference required to trigger that result.
Maybe if support settings in current slicers would support printing a cooler layer over just the support material base you could get this to work… maybe. The next layer would print hot so it bonds to the cooler one below but leaves the delaminated layer/gap (next layer down) above the support surface for easy removal later. The problem is that if it is not sticking to a support layer from being too cold you might get a pile of goober like a bad first layer that does not stick to the bed. I’ve seen this happen with PLA on PVA before but I think it was too hot in that case.
The thought that keeps coming to mind is that anything you do to make it not stick to itself could cause problems for the layer above. There needs to be something else different in the printed properties that exposure to a third environment (water, solvent, heat, pressure, UV light, ultrasonic, dye, color) triggers a clean separation or breakdown of the support material.
With the material itself used as both support and structure you are limited to the support material needing to be accessible from outside the print in order to remove it.
Musings: What happens to PETG printing on PETG if one roll is oiled with vegetable oil or something like silicone? It would need a two nozzle system so as to not contaminate the the other spool with oil residue left in the nozzle.
Regarding the musings or oil or silicone on PETG, I think a purge tower may help.
I guess that with temperature differences alone, you would need to find a sweet spot in temperature difference and that may be tricky. My closest experience is ABS delamination from a low temperature.
Thanks for your opinions on the matter.
The problem with dropping nozzle temp on the first supported layer is that that layer won’t bond to the rest of the print well either. But I think a super-blast of cooling air selectively over supports would help decrease bond strength. Maybe not a lot, but it should help, and wouldn’t be TOO hard to program into a slicer.
Appreciate the post Nathaniel. Commenting for further updates.
@Adam_Steinmark No problem. I enjoy the pursuit of knowledge. This is obviously a topic that the community needs to figure out better. I myself am not likely to use the knowledge for PETG, but oh well. Maybe I will be able to adapt the knowledge for whatever filament that I use.
I think the cooling air may be a bad idea since it may effect the non-support material for the layer. That might be useful when stacking prints though.
@David_Sherwood well yeah that’s possible with any dual nozzle setup. Prusa is working on only using soluble supports for interface layers with their multi material system but PVA extrudes at too different a temperature to be used with PETG in the setup. You’ll most likely see this Selective Soluble Support feature in the Prusa edition of Slic3r when they start shipping their kits.
We came up with nothing for a second filament. That’s is why I made this topic for using PETG as the only filament.
@David_Sherwood I have also thought about the idea of a paste extruder involving support material system. I honestly think dough might make an okay support material as crazy as that may sound. Seriously, just water and flour mixed in a syringe for extrusion. It would cook from the heated bed and nozzle temperature.
Interesting idea. If you guys want to mock up a concept I’ll incorporate it into the CoreXY I’m designing and let you know how it works.
@Adam_Steinmark I do not see a need for any specific design as long as a printer has a paste extruder and a hotend and they are both set to have the same height from the bed. After that, people can experiment away with support material, dye or whatever.
I thought about this idea last night and if you’re going to take up space for a paste extruder and and time to calibrate nozzle height, why not just use a separate extruder and hotend? Then you could use it for PVA filament, or not PVA filament.
If nothing else, there is always value in trying something new. If nobody tried something new, I am sure we would all live in caves still.