What to use to apply acetone, and getting rid of white marks from support matterial

[Lincoln K]

I just did a print.  In it, most of the support material came off without leaving a mark, but a few spots had the dreaded white lines.

I had read that acetone can be brushed on the area to get rid of it.  I did it with a paint brush.  It worked pretty good, but it made the surface very shiny.  A cool look, but it didn't look good next to the parts I didn't paint on the acetone.

So, I ended up "painting" the whole thing.  I found the paint brush to be a bit annoying because some of the hairs came off and merged with the dissolved plastic and are now stuck on the model.  Also the acetone kept evaporating very quickly.

Anyone else have other suggestions for doing this?  I've seen video of a sort of acetone steam bath, and I'd rather not have to do that.

Lincoln

[Joseph Chiu]

Supposedly, a quick pass with a heat gun could make the white "scuffs" go away.  I have not tried it myself, ymmv...

Lincoln

--
 
 

[Steven Castoe]

https://groups.google.com/forum/#!msg/makerbot/YxDrv8Imn1w/hR87Qmw3WSkJ

--
 
 

[Shawn]

I second the heat gun approach. 1 or 2 seconds should be plenty if the
heat gun is warmed up.

Note though that this does not do anything for the finish (unless you
leave the heat gun in one spot for too long, then all bets are off).
Instead it will take the white marks you see when you cut/break/bend ABS
and reset to the dyed color. If you want smoothing of the pimples,
ridges, etc., use the traditional knife or sand paper.

> --
>
>

[Lincoln K]

Thanks for the heat gun suggestion.

I liked the finish given by the acetone.  I don't want to do it for all my models, but what do you think I should use to spread it on the model?   

[Joseph Chiu]

I've had good results applying it with a microfiber utility towel.  What we refer to as "the yellow towel" in our household.  They are sold in bulk packs at Costco.  Walmart has something similar in blue.  

On Thu, Dec 20, 2012 at 2:15 AM, Lincoln K <mind...@gmail.com> wrote:

Thanks for the heat gun suggestion.

I liked the finish given by the acetone.  I don't want to do it for all my models, but what do you think I should use to spread it on the model?   

--
 
 

[wjsteele]

Another acetone method is to have your part suspended above an acetone bath... If you heat the acetone slightly, it will evaporate past your part giving it a very nice and smooth coating. Two coffee cans on a small coffee cup heater are what I use.

Bill

[Kurt Wendt]

Acetone is already so volatile - and bad to breath it in. Heating it would seem to make that situation worse - unless you make sure you don't breath it in!

 

Yes - I've also had the problem with the Hairs coming off the brush. I was told in a store - in the paints dept. - that I MUST use a Natural Bristle brush - since its the typical polyester brushes that have the bristles coming off! I also like to paint my objects with Acetone - as I really DO Like the nice Glossy finish that results!

 

Also, yeah - acetone evaporates VERY Quickly! What I do is use a shot glass - and fill it maybe  1/4 ful. Then, I quickly do the painting - since I know it evaprates so quickly. But, something I HAVE noticed. Once you start painting with it - a bit of the plastic comes off your model and onto the brush. Then, when you dip your brush back into the acetone liquid - the plastic dissolves into it - and it starts making your acetone cloudy. The MORE Cloudy your acetone which U R painting with - the more plastic is dissolved & floating around in it - and - this actually makes the acetone last longer and NOT Evaporate so quickly!

 

Its just a very interesting thing I noticed - and maybe you could make that to your advantage!

 

L8r,

-K-

[Fastrack]

There was another thread.  Someone found a sprayer for the acetone, this would sound like the best approach to me.  Just make sure you spray the object where there's nothing else that the mist will eat!

Ben

[Fastrack]

Found the thread:

https://groups.google.com/d/msg/makerbot/YxDrv8Imn1w/FDagCdxYp-EJ

I have some pump sprayers... .Bottle is made from PET, not sure what the spray pump is made from.. I was gonna see if it de-solves with acetone.

Ben

[Peter Leppik]

I've done this a lot. It works really well.

Make sure you're using a real heat gun, and not a hairdryer. A heat gun will get much hotter, and melts the surface of the plastic a little.

If you're not sure what you have, a heat gun looks exactly like a hairdryer except for the sticker which reads EXTREMELY HOT! DO NOT USE AS A HAIRDRYER!

          -Peter

--
 
 

[BTHOON]

OR! If you're me, you can use a hot air reflow station if you happen to have one.  INSTANTLY fixes the problem be it the white residue you get from printing in one spot too many times or the white spot you get where you slice off the blob from where the head starts printing the part.  It's like an invisible air brush.  Less than a second, and it's as if it were never there.