French Polish and KTM Waterborne on Same Guitar

[Peter borth]

I am building a classical with Western Red Cedar top and Rosewood back and sides. I would like to try to french polish the top and use the KTM waterborne finish on the back and sides as this will wear better than the french polish. I am a bit intimidated by the french polish technique but have resarched it and watched many YouTube videos on the subject. Does this make sense? Also, are Taklon brushes a good choice for brush applying the KTM? Not interested in spraying. Thanks

[Mark Swanson]

Go ahead and do some French Polishing on a few scrap boards. After you do it a little while you'll feel better, and hopefully make all your mistakes that way. It's nothing to be afraid of trying but you want some experience before you do it on your first guitar top. You learn it by doing it!

[Waddy Thomson]

There are a hundred ways to French polish, but one seems to be consistent in my experience. It's best to err on the dry side for the pad(muneca). It seems illogical, but a wet pad will push around the shellac and remove as much as it puts down. A dry pad, relatively speaking, will build the finish faster. Think of it as an amalgamated finish, vs. coats of shellac. Load the pad with a couple of drops of shellac, 4 drops of alcohol, tamp on the back of your hand to blend them into the pad, press on a piece of paper towel till it barely leaves any mark. I find that combination to be just about right for me, but I use a small muneca - about 1.25 - 1.5" in diameter. Something else may work for you.

[Peter borth]

Thanks for your comments on french polishing techniques and I know it always pays to practice on scrap first. Please also comment if possible on the use of the KTM waterborne finish for the back and sides and if Taklon brushes are a good choice for this. I have read where china bristle brushes absorb the finish so it does not flow as well when brushing

[Jim Bonnell]

I attended a workshop on KTM finishing a few years back that John Greven and Mike Doolin did at a G.A.L. convention. John said he used a cheap foam brush to apply it with good results. About two years ago I switched to Target Coatings EM- 6000 and much prefer it over KTM and it's about half the price. Target has a forum on their site that a lot of guitar builders post on. Ask any questions on brushing and you'll most likely get a response with in a day. Good luck.

[Peter borth]

Thanks. I will look into Target coatings but I have a lot of my KTM left over from a previous job. I used a foam brush and was not all that successful but it was my first try and perhaps did not finish sand and level it correctly. By the way, do you have a good suggestion for a water based grain filler? StewMac has one that seems to work well but stinks to high heaven!

[Jim Bonnell]

I can't recommend any. I use epoxy. LMI used to have a tutorial on brushing KTM-9. I don't know if they still do.

[Jim Bonnell]

Here you go Peter. http://www.lmii.com/carttwo/BRUSHINGKTM-9.htm Hope this helps.

[Jim McConkey]

The first time I got KTM-9, the foam brushes were also highly recommended. Some swear by them, but I had endless problems with bubbles from the foam brushes that completely disappeared when I started wiping on the KTM using an old rag, French polish-style. YMMV. Try it and find what works for you.