The Acoustic Guitar Forum

Go Back   The Acoustic Guitar Forum > General Acoustic Guitar and Amplification Discussion > Build and Repair

Reply
 
Thread Tools
  #31  
Old 02-10-2019, 07:50 AM
bluesman62 bluesman62 is offline
Registered User
 
Join Date: Jun 2014
Posts: 80
Default french polish

Ok ,What is French polish?
__________________
Bourgeois Custom OM SS all mahogany (current favorite )
Santa Cruz vintage southerner
Gibson j-45 1995 banner reissue
Breedlove Winter Limited Edition #8 of 10 OM 2012
Martin 2018 000-28
Martin Jeff Daniels OM
Martin d-28
Martin 1997 Custom
Taylor DN8
Reply With Quote
  #32  
Old 02-10-2019, 08:22 AM
Jackson T Jackson T is offline
Registered User
 
Join Date: Jul 2015
Posts: 24
Default

Quote:
Originally Posted by paulzoom View Post
Isn't a fiddle the same thing as a violin but just playing different style music?
Yes, sorry I am a bluegrasser.
Reply With Quote
  #33  
Old 02-10-2019, 08:29 AM
s2y s2y is offline
Registered User
 
Join Date: Oct 2012
Location: Somewhere middle America
Posts: 4,560
Default

Quote:
Originally Posted by paulzoom View Post
Isn't a fiddle the same thing as a violin but just playing different style music?
The difference is a violin has strings. A fiddle has strangs.

I'll let myself out......
__________________
Acoustic gear:
KR fanned 7 string
Greg German DB7
Limited Edition walnut Taylor 12 fret non-cutaway ES2
Reply With Quote
  #34  
Old 02-10-2019, 08:30 AM
rstaight rstaight is offline
Registered User
 
Join Date: Feb 2019
Posts: 85
Default

Quote:
Originally Posted by paulzoom View Post
I would think there would be a big difference between a piece of furniture and a delicate guitar top. No thanks.
French polish is a thin soft finish regardless of the application. But I completely understand.
__________________
2007 Indiana Scout
2018 Indiana Madison Quilt Elite
2018 Takamine GJ72CE 12-String
2019 Takamine GD93
1963 Gibson SG
2016 Kala uke
Plus a few lower end I have had for years
Reply With Quote
  #35  
Old 02-10-2019, 08:42 AM
zhunter zhunter is offline
Registered User
 
Join Date: Oct 2012
Posts: 2,223
Default

Not sure French polish is too associated with violin finishing but worth a try. If you must fix it, a guitar builder specializing in French polish is the best bet. Folks always say French polish is easy to repair. And it may be if one knows how to French polish. In many places, that means not that easy.

hunter
Reply With Quote
  #36  
Old 02-10-2019, 08:47 AM
JonWint JonWint is offline
Registered User
 
Join Date: Mar 2016
Location: 1 hr from Nazareth
Posts: 340
Default

Photo is not sharp enough to be certain of damage. Find someone who knows how to French polish shellac. Main way to make repairs unnoticeable is to restore a flat surface for light reflection. Process described below removes no wood. Scraping and sanding only removes shellac.

Top mark looks like a dent (compressed wood). Bottom mark looks like there could be some gouging (torn wood fibers) into the tint/stain. If tint is removed than that is a separate fix. Same repair method for dents. Spot remove shellac by alcohol dissolution. Steam to remove dents. Drop fill any remaining depression with platina or super blond shellac. Scrape and sand (400 and 800 wet/dry with olive oil) to level. Polish area with a few coats of same shellac.

Top mark should be 100% unnoticeable. Bottom mark 90% or better.

Photos show repair of 130-year old shellac with drop filling in areas of wood loss. Some smart guy thought wood putty would be a good repair.





Last edited by JonWint; 02-10-2019 at 11:13 AM.
Reply With Quote
  #37  
Old 02-10-2019, 08:49 AM
rstaight rstaight is offline
Registered User
 
Join Date: Feb 2019
Posts: 85
Default

Quote:
Originally Posted by bluesman62 View Post
Ok ,What is French polish?
It's a finish technique for shellac that uses a pad instead of a brush. You get a high gloss with a very thin finish and no brush marks or uneven spray.

Wood Magazine has a very good video on the technique. Stew Mac also has information. Both show the same thing.

The only difference is Stew Mac did a level sanding. If it is done correctly level sanding is not needed.
__________________
2007 Indiana Scout
2018 Indiana Madison Quilt Elite
2018 Takamine GJ72CE 12-String
2019 Takamine GD93
1963 Gibson SG
2016 Kala uke
Plus a few lower end I have had for years
Reply With Quote
  #38  
Old 02-10-2019, 09:33 AM
Steadfastly Steadfastly is online now
Registered User
 
Join Date: Nov 2016
Location: Minto, NB
Posts: 3,639
Default

Quote:
Originally Posted by paulzoom View Post
What I can't figure out is how they got there. The guitar had been handled with care when I used it yesterday. Picked it up today and there they were. I don't use a pick with that guitar.
You got kids and/or pets?
__________________
Mr. Big Hands Playing Wide Neck Guitars
Reply With Quote
  #39  
Old 02-10-2019, 09:53 AM
charles Tauber charles Tauber is offline
Registered User
 
Join Date: Feb 2011
Posts: 5,971
Default

French polishing is a skill that takes a lot of practice to do well. Suggesting that someone who has never done French polishing before repair their own finish is extremely poor advice: the "fix" will be much worse than the current damage. The place to learn French polishing is not on the face of an expensive instrument.

The "polish", itself, is a mixture of shellac and alcohol - and possible small amounts of various resins. The builder of the guitar, being in Canada, will not send you, in the U.S., some polish. The polish is listed as a flammable/hazardous liquid and is very expensive to ship internationally. There are many possible suppliers in the U.S.

The violin family of instruments are typically finished with a brushed-on varnish, not French polish.

Anyone skilled at French polishing should be able to repair your finish, be they a furniture maker or guitar maker.


There are two aspects to the repair. The first is color, the second is reflection. If a custom color has been used - either using a specific grade/color of shellac, or a specific tint - that will need to matched. It might be possible for a skilled French polisher to "redistribute" the existing finish to "seal" the scratches/gouges, depending upon the depth of the damage. If so, that might be all that is necessary, and would be neither expensive nor lengthy, for a skilled, experienced French polisher. (It'll almost certainly be a mess for a novice.)

The second is how light reflects from the surface of the finish. Imperfections in the surface will be increasingly obvious the higher the gloss of the finish, due to how light is reflected from the surface and its irregularities. For the scratches/gouges to be entirely invisible, their depressions will need to be addressed. This can be by steaming, sanding or filling. Again, the face of an expensive guitar is not the place to learn how to do these things. Whether that is necessary depends upon the extend of the damage, not readily obvious just by looking at the photos.


French polish, when cured, is not a "soft" finish. It is thin and can be delicate. While freak accidents can happen at almost any time, leaving an expensive instrument sitting on a stand 24/7 is to invite damage, particularly in an area where there is foot traffic, pets or children. While there are some good arguments for storing guitars on stands those who do need to understand the risks involved in doing so.
Reply With Quote
  #40  
Old 02-10-2019, 10:11 AM
paulzoom paulzoom is offline
Charter Member
 
Join Date: May 2011
Posts: 9,732
Default

Quote:
Originally Posted by MikeMcKee View Post
I once had a very expensive French Polished classical guitar. I had it sitting on my couch and my 35# dog decided to jump up on the couch and it's claws landed on the guitar top and put several scratches in the finish...as I remember very similar to what yours look like. I ended up sending it to Thomas Rein...although it wasn't his guitar...and he did a masterful repair on it. Absolutely could not see any indication of where the scratches were.
Who is Thomas Rein?
__________________
Gibson J-45 Rosewood
Gibson Songwriter Deluxe
Martin OMC-15e
Taylor K66 Koa 12-string
Steve Denvir Custom OM Build #21
Steve Denvir Custom OM Build #25
Elijah Jewel Custom Build Dreadnought

...and whatever the next one is
Reply With Quote
  #41  
Old 02-10-2019, 10:12 AM
paulzoom paulzoom is offline
Charter Member
 
Join Date: May 2011
Posts: 9,732
Default

Quote:
Originally Posted by charles Tauber View Post
French polish, when cured, is not a "soft" finish. It is thin and can be delicate. While freak accidents can happen at almost any time, leaving an expensive instrument sitting on a stand 24/7 is to invite damage, particularly in an area where there is foot traffic, pets or children. While there are some good arguments for storing guitars on stands those who do need to understand the risks involved in doing so.
the guitar was hanging, so children and pets cannot get to it.
__________________
Gibson J-45 Rosewood
Gibson Songwriter Deluxe
Martin OMC-15e
Taylor K66 Koa 12-string
Steve Denvir Custom OM Build #21
Steve Denvir Custom OM Build #25
Elijah Jewel Custom Build Dreadnought

...and whatever the next one is
Reply With Quote
  #42  
Old 02-10-2019, 10:14 AM
charles Tauber charles Tauber is offline
Registered User
 
Join Date: Feb 2011
Posts: 5,971
Default

Quote:
Originally Posted by paulzoom View Post
the guitar was hanging, so children and pets cannot get to it.
Obviously, something you didn't account for did.
Reply With Quote
  #43  
Old 02-10-2019, 10:26 AM
Dino Silone Dino Silone is offline
Registered User
 
Join Date: Dec 2018
Location: Northern New Jersey, NYC Metro Area
Posts: 204
Default

Some corrections and observations:

1) The scratches have to be fixed first. They need to be lightly sanded out. Steaming doesn’t help scratches, and will cloud the french polish near where you apply steam. So don’t use steam.

2) Once they’re sanded out (which you’d want to do in as small an area that gets the job done, you need to spot reapply shellac. There’s no need to redo the whole top, unless you’re really obsessive. The most wonderful thing about a shellac finish is that it’s easily repaired. Yes, the spot you fix will look a little different from the neighborhood, but you’d probably have to look very closely to see it, if you’ve done a good job on the scratches.

2a) Don’t go after the scratches too aggressively - you don’t want to create a deep indentation in the top. You just want to get them to not look quite so angry.

3) Any alcohol will work with shellac - not just methyl, not just denatured. I use Everclear to dissolve shellac. Not as toxic as the methyl, and just as effective at dissolving shellac.

4) Don’t try to replicate the French Polish - as others have said, this is an arcane art, and if you’ve never done it, this guitar isn’t what to learn on. Just go for a spot repair. You can read about french polishing online, but the gist is to work with a very weak cut of the shellac, make a “rubber” from a soft rag and a cotton ball, and rub on a very thin coat. When that dries (in just a few minutes), repeat. Keep doing that until you’ve got the look you like. You can find this all over YouTube. (I realize my description is sketchy - best to watch this done on YouTube.)

5) “Durability” of the finish. Those scratches came from something hard scratching the top aggressively enough to dig into the wood. No finish would prevent that. Removing the french polish and substituting another finish wouldn’t help - if you dig into wood with metal, the metal wins every time.
Reply With Quote
  #44  
Old 02-10-2019, 10:42 AM
MikeMcKee MikeMcKee is online now
Charter Member
 
Join Date: Mar 2009
Posts: 540
Default

Quote:
Originally Posted by paulzoom View Post
Who is Thomas Rein?
https://reinguitars.com
Reply With Quote
  #45  
Old 02-10-2019, 11:33 AM
paulzoom paulzoom is offline
Charter Member
 
Join Date: May 2011
Posts: 9,732
Default

Quote:
Originally Posted by MikeMcKee View Post
Do you know where he is located. Nothing on his website tells me.
__________________
Gibson J-45 Rosewood
Gibson Songwriter Deluxe
Martin OMC-15e
Taylor K66 Koa 12-string
Steve Denvir Custom OM Build #21
Steve Denvir Custom OM Build #25
Elijah Jewel Custom Build Dreadnought

...and whatever the next one is
Reply With Quote
Reply

  The Acoustic Guitar Forum > General Acoustic Guitar and Amplification Discussion > Build and Repair

Thread Tools



All times are GMT -6. The time now is 12:17 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Copyright ©2000 - 2018, The Acoustic Guitar Forum
vB Ad Management by =RedTyger=