Varnishes

[sammyjit]

So I have decided that varnish is probably the better finish to apply to my guitar considering my finishing skills and patience are not conducive to something like a French polish. Therefore, what kind of varnish and how is the best application method of that varnish best resemble a decent looking satin finish? I'm not looking for a beautiful guitar. Just a minimalist perspective to protect the wood and conserve tone. (looking nice is a bonus).

Thanks

Sam

[MaineGeezer]

Though not abut guitars, one of the best books I've seen about the characteristics of all sorts of wood finishes is Gunstock Finishing and Care, by Donald Newell. http://www.amazon.com/Gunstock-Finishin ... 0811707800
It was originally printed in 1949 so it doesn't have information about some of the modern finishes, but the number and types of finishes it does cover is quite amazing.

[ruby@magpage.com]

The bigger question is do want a flat surface with some shine to it, or will you accept some brush strokes. Guitars tend to look good with a nice flat surface on the finish, so any brushed on varnish or lacquer, or even sprayed varnish or lacquer, is going to need flattening (think of the guys sanding on the freshly sprayed car finishes that you see on the TV shows).

With that in mind - spray or brush?

I tend to like a finish similar to the ones you see on 30's instruments after they started spraying lacquer. Not a mirror polish, but certainly flat and shiny:

https://www.flickr.com/photos/ruby1638/ ... 344222304/

Look at the next 6-8 pictures. This is sprayed lacquer, sanded to 2000 wet-or-dry, then Meguaires +9, but I have done the same thing to brushed on KTM-9 water based varnish with very good results.

Ed

[B. Howard]

Perhaps tung oil may be a good choice. Easy to apply, it can be wiped or brushed and forms a good looking protective finish.

[sammyjit]

Probably brush for me. I have some experience spraying paint. I am not the greatest painter with a paint gun anyway. Maybe a wipe on like Shellac. Yeah, no French polish for me. But shellac and alcohol should make a decent varnish right? I may just tung oil the neck and Shellac the body.

[MaineGeezer]

Do some experimentation on some test scraps before tackling the guitar. I have a hunch you'll be disappointed with tung oil. Maybe not, it depends on what appearance you're after, but I certainly was.

I think Tru-Oil is far more likely to give you results you'll like....though again, it depends on personal preference.

Shellac takes a surprisingly long time to get really hard. While it may be dry to the touch in an hour, it may take a week before it won't pick up a fingerprint if you press hard on it. Give it plenty of time to dry before sanding smooth. I had a heck of a time trying to get a truly smooth, gloss shellac finish, and I think part of my problem was that I tried to hurry it.

Do you have an open-pored wood? Do you plan to use a grain filler?

Getting a good finish is a lot of work and takes time, but it adds so much to the guitar. After all the effort you went through to build the guitar, don't be satisfied with a second-rate finishing job.

[sammyjit]

The body is Mahogany with spruce top. The neck is also Mahogany. Should I use a pore filler?

[MaineGeezer]

People do use grain filler on mahogany. It depends on what appearance you want though. If you are not looking for a smooth gloss service, maybe you can get by without it. All I can suggest is to try it on some scrap and see what you think.

I used AquaCoat grain filler from LMI: http://www.lmii.com/products/finishing/ ... ear-filler on black walnut, with reasonable success.

It's the only grain filler I've ever used. It worked, but there may be better ones. My experience with all this is limited.

I was talking with somebody a while ago about finishing. He said that furniture factories figure that 50% of the cost of building a piece of furniture is in the finishing. A good finish is a lot of work.