Re: A Repair, Revisited/Finally Done After 2 Years.

[Diane Kauffmds]

After days of scraping, sanding, scraping, sanding, then scraping some more, with a little more sanding, I got the box closed and bound, and the guitar ready to finish. I've also got the fingerboard ready to go. It's finally time to french polish!

Man, did this guitar have a LOT of finish on it. My biggest challenge was getting the stuff off from the heel and surrounding shoulders. I found that the curved cabinet scraper fit right into the curve of the heel, so I could get right up to the heel on the shoulder. The heel itself presented challenges. My concern in both areas was going with the grain while sanding/scraping, which is pretty difficult to do when the guitar is in the way of things. However, the entire guitar is sanded to 320 and/or scraped and smooth as a baby's bum. French polishing will commence tomorrow.

scraping waist.jpg

scraping heel.jpg

[Diane Kauffmds]

The end result...did I mention that I had to do a lot of scraping and sanding??? There are 2 spots where I can see repairs done. One is under the heel cap and the other is on the left shoulder by the binding. I just left them alone. They add character. After all, this guitar is at least 40 years old and probably older.

front ready to finish.jpg

back ready to finish.jpg

[MaineGeezer]

Nice!

[Diane Kauffmds]

I started French polishing, so I see an end to this tunnel.

After sanding and scraping off the old finish, I found some white substance in some of the pores. It's not sanding residue and I didn't use anything on the guitar, except sandpaper and my scrapers. Whatever it is, it's very deep in some of the pores and I cannot get it out, even with sanding. The old finish was very dark, so it wasn't noticeable until I got it off.

I took the raw guitar to our local Woodcrafter store and talked with their expert. I was fortunate that a local luthier, who works part time at the store, was also present. The guitar is made of lesser quality Brazilian Rosewood, with a fine quality of figured BW laminated over the top. They pointed out a couple of wormholes in the BW on the inside of the guitar sides, and the back is made of 4 pieces of mismatched BW (I figure probably leftovers), which shows the more typical broad dark streaks.

I wish I could bottle the smell of the wood as I sand. However, this left me with a problem with this white stuff that's down in some of the pores. I tried to brush it out with an old tooth brush, and I tried to get it out with my fingernails, but whatever it is, it ain't budging. If I sand anymore, I run the risk of sanding through the laminate, which is extremely thin. I always clean the guitar with naphtha and I've tied to get the white stuff out using acetone and alcohol.

Even the mahogany neck has some in it. I thought i could sand it out, since the neck is solid, but I keep sanding and I swear I'm finding more. I've made the decision that I can't sand anymore, without damaging the guitar body. I have some leeway on the neck, so we'll see what I can do with it. I'm only french polishing the box; I'll use satin polyurethane on the neck.

So, the white stuff has to stay because I won't risk damaging the laminate. The guitar may been refinished in the past; the laminated wood has been sanded through, under the heel cap. Here are photos after the first fp session. I completed a second one this morning and I'm about to start a third.

fp session 1.jpg

fp session 1a.jpg

white pores.jpg

[Kevin Sjostrand]

Might be old finish caught in the pores, did you try lacquer thinnner? I've used that on EIR and Santos Mahogany that had mineral deposits in the pores, and the disappeared.

[Diane Kauffmds]

Might be old finish caught in the pores, did you try lacquer thinnner? I've used that on EIR and Santos Mahogany that had mineral deposits in the pores, and the disappeared.

Thanks Kevin. I'll give it a shot.

[Diane Kauffmds]

I'm keeping myself busy with french polishing, as Winter Storm Jonas is beginning to make its appearance in earnest.

I started on the top this morning and have just completed session 2, so I'm still building up. I need to put more muscle behind it, but my "get-up-and-go" has "gotten-up-and-went". However, progress is being made...

[tippie53]

lookin sweet

[Diane Kauffmds]

lookin sweet

That means a lot coming from you John. Thank you.

[Diane Kauffmds]

I'm finished with the top. I still have a little to do with the sides and back, then the french polish will be complete.

Although it's probably heresy, and most of you will think I'm completely nuts, I prefer my tops to be a more of a polished satin, rather than a mirror finish. French polishing for the most part, makes a high polished finish, so I take it back a step. I polish the top until I can make out the parts of the florescent work light that hangs above my table, and as long as I can make out the design of the stained glass window across the room, I figure I'm done.

I take a piece of 0000 steel wool, and rub it gently over the top, which of course, takes off most of the shine. Then I use nothing but alcohol on my polishing pad, to gently "polish" the surface. In reality, the "pure" alcohol is probably at least 1/8# cut, plus the pad contains a lot of shellac. I gently buff the top until I see a more diffuse reflection.

I could stop before reaching that final high polish, but I found that when I do it this way, the surface is much more level.

Photo #1 shows the top with the high polish, and the window reflection.
Photo #2 shows the top highly polished and the reflection of the light
Photo #3 shows the top finished, with more of a satin finished; you can see the difference between this photo and #2

polish 1.jpg

top finsihed 1.jpg

top finished.jpg