French polish updat

The Achilles' Heel of Luthiery
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jread
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French polish updat

Post by jread »

Thanks to handy tips from Diane and lots and lots of sessions, I think I'm getting the hang of it.

Still using canned clear shellac and denatured alcohol mixed variously. I'm interested in using different solvent and dissolving flakes perhaps if it will bring out a bit more color or clarity tho, this looks pretty great.

This finish is uniform and polished on the outside surface. I think it still needs improvement in the direct eye view. Perhaps more perfect surface prep. Took me many tries to get used to Colortone water based pore filler and I had to a frustrating balance sanding that smooth with sanding it off. The sides especially were hard to sand. Basically, this story is all learning to properly use sandpaper and then learning to feel the shellac/alcohol/oil ratio in the ball/rag/muneca thing so that you can put on more coats if you want, smooth them out, or polish.

I polished until I could read the IU sticker in the shop light. :D

The binding had some weird tearing issues as you can see when I scraped. Just in that little spot near the end graft. I decided to leave it in as the rest came out nicely. Or I could re-bind it. Oh well.
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Diane Kauffmds
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Re: French polish updat

Post by Diane Kauffmds »

Good job!!! I'm proud of you! it looks great.
Diane Kauffmann
Country Roads Guitars
countryroadsguitars@gmail.com
tippie53
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Re: French polish updat

Post by tippie53 »

looking good
John Hall
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ruby@magpage.com
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Re: French polish updat

Post by ruby@magpage.com »

j

Looks delectable. Did you polish with a machine or by hand? If by hand, what was your abrasives schedule?

Ed
Ed M
Danl8
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Re: French polish update

Post by Danl8 »

I think you have figured out how to french polish. Looking good!
jread
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Re: French polish updat

Post by jread »

ruby@magpage.com wrote:j

Looks delectable. Did you polish with a machine or by hand? If by hand, what was your abrasives schedule?

Ed
Thanks so much. As I alluded to, I got a bit overwhelmed with all the instructions and information on this stage and gave up being methodical and each session over the last few weeks has been just learning what the result looks like after I try various things, then sanding back. As I learned to get the pores filled, I re-learned the basics of sand paper and a sanding block. I found that I had to sand every bit of filler that was not inside a pore and that without being super steady with the block, you can scuff and scratch deeper than your grit very easily forcing you to drop back to lower grits. Frustrating.

All polishing done by hand with t-shirt material tightly wrapped around a ball of t-shirt material. I was having pain issues but I think I've positioned myself so I won't end up w/ tennis elbow.

Then, the schedule was pretty set once the top was smooth to 600-800, i'd say it went something like this. The problem is that I kept having problem spots requiring me to drop back to 600 grit so it was not a smooth schedule.

A session was basically trying not to ruin the surface with my cloth. I'd try to go from "cleaning off oil", to "moving wet shellac around", to " polishing semi hard shellac", to " cleaning streaks" in each session which was about 30 minutes. I wouldn't say this matches any advice that was given to me but here's where I ended up.


Generally:

a few wash coats, then next day
sand up from 220-600.
3-4 sessions of building up shellac over a day, next day, sand to 600/800, 3-4 more sessions
next day, sand to 800/1000, 3-4 more sessions
next day, sand 1000/1500, 3-4 more sessions
next day, sand to 1500/2000, 1-2
next day, sand 3000. just polish
I repeated 3000 then felt like it is not quite finished but not sure where to go. Letting it dry for now.


Quoting Diane somewhere in another thread, "there are no short-cuts." I had to learn that if there was an area that needed addressing, I'd have to re-do the whole surface putting me back a day or two i this list. I hope it would be more methodical as one gains experience.

also, sandpaper is expensive.
Diane Kauffmds
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Re: French polish updat

Post by Diane Kauffmds »

Spiriting off will take care of those tiny polish Mark's. Also, you can use micro mesh followed by Novus #2. Since you've sanded, I think that micro mesh followed by Novus is the way to go.

Here's another thing you can pick up off of amazon, or any woodworking site. You'll want your finish to dry and harden before going any further.

Just go through the micro mesh grits according to their color chart. That'll take you to 12,000 grit. Then, I finish off with Novus #2, which is actually a plastic polish. I use a small amount on a dampened cloth.
Diane Kauffmann
Country Roads Guitars
countryroadsguitars@gmail.com
ruby@magpage.com
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Re: French polish updat

Post by ruby@magpage.com »

I may have this wrong, but there are a couple of ways to use shellac. One is to brush on a few coats of higher cut material to get some build up, then level and polish. I have done this with success.

Another is French Polish which is adding minute amounts of shellac per coat and using your technique to NOT require any abrasives. Done right, the last coat with oil leaves a shiny surface. I have never done this with success.

Ed
Ed M
Diane Kauffmds
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Re: French polish updat

Post by Diane Kauffmds »

Spiriting off, which is polishing with a gradual increase of alcohol to the shellac, is where the real polish comes out. It took me a while to learn how to do this.

I look at spiriting off as stage 2, almost akin to starting over completely with a different objective. Stage 1 is the buildup of finish. Stage 2 is polishing it in, compacting it more for hardness, and eliminating swirls and other imperfections.

I've done "complete" French polishing, but I'd be a liar if I said I didn't use micromesh and Novus 75% of the time.

It comes down to the project, and how much time I can spend on it.

I want to mention that I keep the alcohol that I use for french polishing in a jar, and it's never pure alcohol. I always add a bit of shellac to it. I use a plastic pipette to dispense the shellac and alcohol to my pad. I clean it out in the alcohol, and I add a pipette or 2 of shellac when I refill the jar. In the end, the alcohol is probably a good 1/4 to 1/2 pound cut.
Diane Kauffmann
Country Roads Guitars
countryroadsguitars@gmail.com
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