Solvents for filament-smoothing?
I was reading an online article about some people who 3D-printed feed horns for satellite antenna dishes. The surfaces need to be extremely flat, so they used solvents to smooth the printed objects. They chose to print PLA and used dichloromethane (methylene chloride) as the solvent. Another alternative they mentioned was to print ABS and use acetone for smoothing.
A question for those experienced with filaments and solvents: If you were choosing, what filament and solvent would you use? I'm actually currently printing more with PETG than with PLA (and have never printed ABS). Not sure which would be easiest to smooth, and what solvent would be best/safest to work with.
RE: Solvents for filament-smoothing?
Another option would be PVB, which is quite soluble in isopropyl alcohol, and is easy to print.
Is this going to be outdoors, exposed to rain, hot, cold, and sun? I think that would argue for PVC.
ABS and acetone is relatively easy 'though you will need enclosures and fume extraction for the print. PLA and CH2Cl2 is potentially quite dangerous and the reagent is banned or restricted for unlicenced use in many countries; it's tricky to handle and even keeping it in the bottle can be hard in a heatwave. Go to ABS first and get plenty of experience there before you try PLA.
Cheerio,
RE: Solvents for filament-smoothing?
Remember that ASA is just as easy to smooth with acetone and prints much more nicely than ABS and has almost no odor. Plus, it's more UV resistant and will resist yellowing longer than ABS.
I've done a bit of PVB. It prints as easily as PLA and is easy to smooth with IPA fumes. But I found it to be more fragile than ASA or PLA and it's certainly not suitable for outdoor use. I haven't really seen much use for it short of decorative objects such as vases, which I'm not really interested in.
And yes, you do not want to go down the PLA route unless you have a chem lab in your basement...
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE: Solvents for filament-smoothing?
Thanks for all the comments. This is for a portable antenna that would be taken outdoors for a couple of hours at a time, but generally would be stored indoors. So that's making PVB sound interesting. ASA also sounds like a possibility.