After sanding a will have small scratches and some time you can see them trough paint. How can I fix that? I did not want to pain 5 layers of paint but whatever fix is please let me know?
Thanks,
Gumiflex
I use Gunze Sangyo Mr. Surfacer 500 and brush it on to the scratches. It dries fast and sands very well. I try to put on as little as possible. If it is going to be under a bare metal finish I might use super glue, and sand it within 15 minutes.
Another idea before applying super glue or Mr.sufacer and sand over again with a very fine grit sandpaper. I always start with a course grit and work down to a fine grit when sanding. You will find this often removes big and small scratches.
Air Master
Gumiflex,
Sanding is a process of abrasion - basically a surface (your model) being rubbed with a rough substance (the sandpaper) … the paper “abrades” away some of the plastic (because the grit is far harder than the plastic), and this produces the scratches you’re trying to get rid of.
The way to go is to use progressively finer grits of wet or dry sandpaper on your model.
Ever notice the number on the back of the sandpaper? That’s a grit rating - the lower the number, the rougher the sandpaper (and the bigger the scratches).
The higher the number, the smoother the paper will be, and the smaller the scratches.
Using a progressively higher number (320 to 400, then 400 to 600, then 600 to 800, then 800 to 1200) will make the scratches get smaller and smaller, eventually disappearing altogether.
Using a surfacer or primer can sometimes fill smaller scratches, and sometimes you need putty because the scratches or pits can be too deep for a surfacer.
And as you know, the smoother the surface, the better the paint looks when you apply it.
Patience is the key.
If you are going to apply a natural metal finish you can go one step further and polish the plastic after you have sanded the surface. There are several brands of plastic polish available. Be sure to clean the surface before painting as some of the polishes will cause adhesion problems if they are not cleaned from the surface.
The finest grain sandpaper I can get my hands on is 1500 grit at a hardware store, usually in the automotive section if not stocked with all other sandpaper.
Polishing abrasives are yet another option. These are cloths that have a grit of 4000, 6000, 8000, and even 12000. For natural metal finshes I use the iterative progression of sanding with finer, and finer grit sand paper and polishing abrasives up to either 4000 or 6000 grit. Usually works just fine. The 8000 and 12000 grit are more suitable for lightly buffing out those unfortunate, but inevitable, oily finger prints that mysteriously appear after a nice paint job, but before sealing with Future. All your really doing with the light buffing with the 8000 and 12000 grit polishing abrasives is moving paint around. You can wear the paint off so use this technique with caution to avoid having to repaint.
Thank you all for a kind replays. I use 800 or 1200 since I build 1/72 and sometime a get this small scraches witch I try to fix.
Quagmyre; for some Polishing abrasives I use coffee filter, very fine “sending paper”
Gumiflex