How To Use Wood Filler Properly?

[iskim86]

ok so I sanded down my body to the filler (i think?) and the wood is not smooth - all fuzzy and "peach-like". this is probably bad when I have to spray primer over it right? so I'm guessing I need to use wood filler to fill these holes. how would I need to apply it and sand it down?

thanks

[iskim86]

oh yeah i'm using the elmer's brand wood filler, I think it's used primarily to fill small cracks and such... it's yellow color

i just realized alder does not need grain filler. oops.... but there originally was when I sanded it down.

Edited April 15, 2007 by iskim86

[SwedishLuthier]

What you saw was probably not filler but primer. That is a thicker laquer that is used to even things out for the following colour coats and later the clear (all this asuming you had an opaque colour).

It sound to me that you have used a pretty coarse sand paper on a relatively soft wood (aslder). You need to use progressivly finer sand paper to take care of the sanding marks and the wood fuzz from the prior grit. You should do this until you have sanded with at least 180 grit. Some take it way further.

[pariah223]

Yea like swedishLuthier said, sanding with course grit removes material and imperfections in the wood, but leaves its own tool marks. As you go down the line with the sandpaper, you remove the marks from the previous sandpaper, but you leave new marks with the paper your using until you get down to the 180-220 area where the marks left are small enough that a finish will cover them

[slash//]

By the sounds of it you definitely need wood filler but be careful of what type you get. If you get the wrong kind for a different wood the color will be different, obviously. But even if you do get the right kind it still will leave a mark and you'll now it's fake. It's basically only good to use it if you're going to paint your guitar and cover it up.

As for applying it just put some on a putty knife and fill it in as if it were crack fill for a wall. Then sand it down. The brand I use is supposed to come off with water, so you can do that too.

Edited April 23, 2007 by slash//

[ihocky2]

What and how to use is depening on what you are trying to do. If you are trying to fill the holes from the wood pores, then you bought the wrong stuff. The Elmers wood filler is used to fill in nail holes and such in molding and the likes. It is too thick to entirely get in the wood pores. Second problem with it is that it shrinks back something terribly over time. Top fill the pores, you need grain filler. You can get water based or oil based. Each has their pros and cons. I know that natural colored waterbased wood filler is white, so your only choices with it is to either dye it or paint over it. The oil based doesn;'t shrink back as much and is better to use when using a transparent finish, but it takes several days to dry. If you have cracks or holes you are trying to fill the Elmers is more suited to that, but again it shrinks back a lot. You are better filling with either epoxy or auto body puty, and the better the brand the less it will shrink. Bondo doesn't shrink too much, 3m either doesn;t shrink is is extremely minor. Your best bet is to do a search for grain filler on this site. There is a ton of info.