Morning.
I recently tried using acetone for the first time, to strengthen a part. I don't have a large pot or bottle I could use for vapor treatment (besides, it has to remain mechanically accurate in some areas), so I brushed on acetone. This worked generally, as it merged the layers nicely, but it left a whitish residue all over the parts, that won't come off easily. I tried soap and water, more acetone, using a scrubbing brush to no avail.. any ideas?
The acetone was pure acetone, no nail polish remover or anything.

Acetone don't work well on all types of ABS plastic (It don't work on PLA). Some ABS formula have charges inside that helps print better, but are revealed in white under acetone treatment. Note, acetone works better on pure ABS filament BUT, that ABS wraps a lot. IMHO ABS don't need to be strengthened. If the printing temperature is good, layers will melt as well as they can. If you want to reduce layer marks, sand or polish the part. If you like the shiny finish, use varnish.

Edited 1 time(s). Last edit at 01/24/2015 07:57AM by Zavashier.

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Collective intelligence emerges when a group of people work together effectively. Prusa i3 Folger (A lot of the parts are wrong, boring !)

Is it pure acetone?
Some is sold with oils and other ingredients, especially if intended for cosmetic purposes. Nail polish remover for example.
This could be your white deposit.

Ive got pure acetone bought in 5 litre containers and ive not seen any residue when ive glued abs things together or played with brushing it on.

Gordon

It's definitely pure, I checked the contents. I'm guessing the residue actually comes from the ABS itself, as it's more pronounced where the actone turned into slurry.
As for strengthening, it's mainly to avoid the layers from coming apart under stress and vibrations. Just an additional precaution.

Try pouring some of your acetone from the container onto a very clean sheet of glass. If there is any residue after it dries off then it could be that the problem is your acetone. If not, it seems likely that the dye is more soluble in the acetone than ABS is - the white cast is the plastic (or one component of the plastic) minus the dye.

I've had the same problem and I can't explain it. I can cold vapor or hot vapor my parts with acetone and no coloration but when I use it to glue parts together I get white streaks wherever the acetone hit. Now all I can say is mine comes from the hardware store and just says Acetone on it. No where else on the can does it mention ingredients so I don't know if there is anything else in it. From time to time I have also dispensed it with glass lab eye droppers and over time the eye droppers have a white coating on the inside making them kind of milky colored so that must come from the acetone in liquid form yet not in vapor form.