Official Luthiers Forum!

Do you you sand between wash coats? I have applied 2 wash coats of seal coat 1 lb cut (used Zinsser's seal coat cut 50% with denatured alcohol). I brushed it on but still see some streaks, and even areas. Should I try to level sand this coat before appyling the top coat layers.

Thanks
Richard

If it's the top of the guitar you're talking about, it sounds like you brushed on too much. A wash coat needs to be fairly wet, but not THAT wet. Very hard to describe. Sort of like wash it down with a rather damp cloth and then wipe it dry, such that everything has been wet but you leave everything damp with no wet lines. Done literally in seconds. Finished in the time it takes to unload your brush once. When it's dry you will have raised the grain and maybe some "fluff". Knock that off with a fine sanding then into another wash coat. You shouldn't have to be levelling streaks. Depending how it's hardened off, you may be able to "wash" it down with alcohol so that you "wash out" the streaks. What you have left on is then equivalent to a first wash coat, which should look something like this, which has two wash coats:

Ignore the magnets etc. I was just setting up their positions for a magnetic arm rest. It's the only shot I had which looked like there was any finish on at all! (See the reflection, bottom right). The "streaking" that you see is all wood colour, not finish.

If you have wood which easily bleeds colour, be very careful how wet you get things and work the bleed areas away from your top (i.e. work from "centre" outwards) but stay grain aligned. Much easier to show you then try to tell you!

If you're working backs and sides which bleed a lot of colour, it's a different game again...

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au