Was playing around with some automotive body filler putty today in hopes of looking for an alternative to poly putty used by modelers. I wanted something that was cheap and easily available in my parts of the world so I thought of trying out automotive body filler since I read from some forums that it can be used as an alternative to poly putty that is usually used by modelers in scratch building model kits.
I don't remember anymore what forum I got it from but the helpful poster recommended to thin it down with acetone since automotive body filler is quite tough which would make filing it down a difficult task if you are working on small pieces. Instead of using acetone I decided to go the opposite tack and just add more filler into the automotive putty in order to thin down the resin that's already existent in the automotive body filler. More filler makes it easier to sand, at least that was what I was hoping for.
That lump on the left is composed of 1 part automotive polyester putty body filler to 1/2 part calcumine powder. The one on the right is 1 part automotive polyester putty body filler to 1 part calcumine powder. The one on the right has a much rougher texture than the one on the left. With that I decided to play around with the one on the left.
In mixing the two together I first mixed the calcumine powder and polyester putty. After I'm sure that they have an even color, meaning that the powder is thoroughly mixed with polyester putty, its only then that I add in the hardener of the polyester putty. Depending on the amount of hardener you put the putty can harden quickly.
I don't remember anymore exactly but I think the calcumine powder costs about 22 cents per kilogram. The cheapo automotive putty body filler costs about $3.40 in my parts of the world for a small half liter can. I thought of using calcumine powder because that was the filler that we were using when I was taking up a class on resin casting for figures. Only now I realized that I should have used talc powder because it has a smoother finish than the calcumine powder.
Took out my files and handheld router and tried shaping the small lump. After an hour I was able to polish it down to this. No design in mind really just free hand. Knowledge gained from this experiment will definitely come in handy in the future for scratch building model kits.
Worked on it some more during the day when I had time. Turns out that it can be easily sliced off with an X-acto knife, which makes carving even better. No more playing around with plaster of paris for me! Be sure to work with a particle respirator mask because this stuff is toxic for the lungs.
