Solved: Will BBL ABS support a proper solvent weld?

I’ve read that it has a lot of additives in it, to the point where a vapor gloss doesn’t work so well, so I’m wondering whether a full-on solvent weld between two parts each printed in BBL ABS using acetone as the solvent would work or not. I’m under the impression that with regular, pure ABS, that such a weld would work.

Anyone tried it, or otherwise know?

Yes I frequently solvent weld BBL ABS parts together. I also dip parts in acetone to smooth and seal them with great success. A quick dip gives parts a hardened outer surface with the look of a painted clear coat. You can no longer feel the layer lines with your fingernail.

Example on the left is as printed, on the right is dipped.

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Does it work the same with ASA too?

Yup it does. (20 characters)

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One last question: Are you making an acetone-abs “slurry” to then apply as the solvent to do the welding, or are you using a commercial solvent, such as:

I think I may even have some of this leftover from when I was solvent welding pvc pipe for my irrigation.

I’ve used both a slurry mix when I needed a colour matched glue and the commercial stuff when looks weren’t as important.

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Amazing.
I´ve failed to smooth BL ABS with acetone, yet I used the conventional vapour method, which proved trustworthy with third-party ABS.
I will give the dip method a try.
You dip it and let it dry. Which surface do you place it on during drying?

Yes, I couldn’t get the Bambu ABS to vapour smooth either but the dip method seems to work for me.

I dip the part for approximately 2-3 seconds (almost fully submerging it) and then remove while giving it a shake to remove the excess drops. I then place the unsubmerged face on a glass plate to dry. While the part is still wet/soft you can redip it to fix any flaws or runs from excessive acetone. The part is dry to the touch in 20-30 seconds and fully hardened in a couple hours. Once dry you can redip to smooth the surface more but the affect seem to have diminishing returns each time.

For parts that require fully smoothing/sealing I find that dipping half of the part, letting it dry and then dipping the other side seems to work best and there isn’t a visible line.

I tried “painting” on acetone but could never get an even finish that I liked. I may try spraying it for parts that are tough/too big to dip.

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Thanks. I have some BL ABS spools stored, which may now see hope to be used.

The main reason I chose ABS was the easy smoothing; the prints were large, and I was so confident that I made the mistake of setting large layers and using a 0.6mm nozzle.
I already accepted the failure, so I am more focused on testing and learning while trying to recover it. I’ve been testing some filler pastes, and all seem to work, yet while sanding ABS is doable, it takes too much time and hand work while masked is something I quickly pass. I also tried the Dremel with different grits but never felt in control of the outcome.
I bought some plastic prime filler spray, but I need a better surface before testing.

I’ve some small prints for which dipping may be feasible. Do you have a specific container for the purpose? And do you reuse the acetone?
After reading your comment, I started planning the test, but it may take a significant amount of acetone.
I am sure I do not have any sealable large containers for the large prints, nor enough acetone.

Spraying would be great; I thought about it, but by reusing an old nebuliser. Yet, I still need to verify possible risks due to acetone flammability.

You might be interested in a hand pump acetone sprayer/mister, such as this:

https://a.co/d/gee2rnX

I purchased this exact model for spraying acetone onto PCBs to clean off the flux but I haven’t yet gotten around to trying it out or using it.

That solution seems excellent… if you try it, please share the experience.

I will try to find one in the EU to avoid customs taxes.

I also do a lot of PCB assembly and have tried a bunch of different flux residue removing techniques. Word of warning on the the acetone for cleaning. Not all thru hole connectors are acetone safe and will melt. Ask me how I know lol.

The best thing I have personally found is warm wd40 especially if the flux residue is still tacky. Then a wash with windex and the boards are squeaky clean.

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I use wide mouth glass jars mostly that can be resealed and are stored in a flammable goods cabinet. I do reuse the acetone but only for similar coloured parts as some of the pigment is left behind during the dip.

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What a small world we live in. I have never before heard of that technique, but if you’re saying it works great for you, then I look forward to trying it.

I settled into using IPA and a toothbrush, which is why I never got around to trying the acetone sprayer. I was thinking too far ahead when I bought it. Acetone does work faster, but it’s actually too good of a solvent for the task, dissolving things I didn’t want dissolved, such as silkscreened text and artwork on the PCB.

I forgot to mention that unfortunately the dip method isn’t going to smooth this.

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Does acetone dipping help for the lines under a bridge?

If you sand them smooth first it will help. I haven’t found a way to smooth really rough surfaces just by dipping. I need to experiment more with longer dip times.

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Have you ever gotten any deformities in the part from dipping?

Deformities as? A quick dip keeps all edges sharp as you can see in the picture above.

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I have read that it can deform or warp, but I think that is only if you leave it in long. You probably never had the problem because you only do it for a few seconds.

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