I’m pretty new to PETG, and have been really struggling with it compared to PLA. My latest print of this part is dimensionally accurate, but I need it to be air tight. It is very much not at the moment.
I have a Flashforge Adventurer 3, so the hot end and nozzle are one interchangeable unit. My higher temp nozzle is 0.6mm. My 0.3mm is only capable of 240. My last print was 0.2mm layers, with the 0.6mm nozzle at 245C. I used 15% overlap on my walls, and in order to keep my nice dimensions I had my cooling fan on.
Anybody have any advice on how to improve the seal? I’m tempted to try more overlap, with random start locations per layer. Do you think if I run it hotter I can get the layers a little thinner? Any advice would be appreciated.
This probably isn’t what you want to hear, but if I need something watertight, I use a material that can be smoothed during post-processing using a vapour bath (I prefer PVB, but ABS or HIPS should also work). Smoothing the print effectively causes it to self-coat. PETG may simply not be the best choice for your application.
Yeah, it is not a super friendly material. I really wanted this piece to be at least translucent, as it would save having a separate piece for an ink window, and it is just cool to see the ink in the feed. Looks like there is a clear PLA on sale on Monoprice right now, I just went ahead and ordered some. I have my PLA settings dialed in pretty well, I can probably get it down with that. I’m still going to keep trying with the PETG, though.
PLA is not one of the filaments that can be vapour smoothed with household chemicals afaik. I don’t think you’ll have more success with than the PETG. Sounds like PVB might be more suitable for your project, since it’s transparent and can be smoothed with IPA.
Technically, any filament can be smoothed if you’re willing to use sufficiently noxious chemicals. Ethyl acetate is apparently the least noxious smoother for PLA—it’s used in perfumes and can be purchased off Amazon, Ebay, and other large marketplaces. Not something you’d have lying around, but I don’t think it’s terribly toxic, either (never tried it myself). Still, check some MSDSs or the like before you shoot off and buy some.
Well, that’s why I wrote household chemicals :) TIL about ethyl acetate though, I’ve always heard chloroform being the best solvent for PLA.
Well, I only claimed that ethyl acetate was the least noxious, not the most effective—Wikipedia claims a low overall toxicity, and use in skin contact and even food applications. Chloroform seems like it would be slightly higher-risk. 😉