To remove excess putty can rubbing alcohol or nail polish remover be used without damaging the plastic. Sanding only scratches up the plastic. thanks
If you’re finding the need to remove excess putty you made the cardinal mistake of applying too much in the first place. You can use either, but be careful when using nail polish remover or lacquer thinner as it may damage the surface of the plastic. Then you’ll find you need more putty to fix the problem you just created.
Putty is best applied in small amounts, thinly spread to the area where you need to fill. You can use masking tape to act as a curtain to keep putty from touching surrounding areas.
Look at using the appropriate tool for the job. There are sanding sticks known as Swizzle Sticks which allow you to sand narrower swaths.
Make sure you sue the nail polisher remover with acetone, its the acetone that does the trick. But pure acetone is too strong and will harm the plastic, that’s why you need to use the nail polisher remover - it’s already diluted.
I use acetone to remove excess putty-well, actually, it’s part of my process for applying it.
Hawkeye is right, you want to apply no more putty than is necessary. And everyone is right, you want to be careful, because acetone is a solvent, and in sufficient amounts and time of exposure, it can dissolve styrene.
With those cautions in mind:
I use two methods.
In the first method, I apply putty to the area with a toothpick, troweling it into a seam, for example, and before it sets, removing the excess with the toothpick. I also have a dental tool used to trowel resin into holes in a tooth, for the same purpose. Once I’ve got most of the excess removed, I take a cotton swab dipped in acetone and run it over the area, removing more of the excess and leaving putty only in the area where I want to apply it. Sometimes it takes a couple of passes, but I repeat as necessary till the seam/gap looks good.
In the second method, I mix putty with acetone in one of the wells of my palette, using an eye dropper to add the solvent a drop at a time, till I have a thick liquid. I call this my homemade Mr Surfacer. I use an old paint brush to apply it to the seam/gap/depression. Again, as the liquid evaporates and the solids set up, I can adjust with another brushload of acetone or cotton swab. And as the mixture dries on the palette, a couple of additional drops of acetone will bring it back, even days later.
In either process, I apply the solvent only for seconds, that is, I’m careful not to use too much, so it evaporates rapidly.
For this, I use acetone from the hardware store, rather than nail polish remover. Nail polish removers are weaker solutions, as was noted above, and often they contain scents for the ladies, that I don’t need. And a can of acetone is usually cheaper by volume than nail polish remover. Also, it can be used to clean tools. The putty that I use is Squadron white, though this will work with other putties, like 3M’s blue or green.
My point is to illustrate that you can use these materials with no problems. I know modelers who use lacquer thinner for this application, too, though I avoid that because of the strong fumes. You just need to apply care, just as you do in other processes in our hobby.
Hope that helps!
Regards,
Brad