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Tips for French Polishing with the bridge on?
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Author:  jfmckenna [ Mon Jul 22, 2019 1:02 pm ]
Post subject:  Tips for French Polishing with the bridge on?
I don't FP with the bridge on but now I am forced to becasue I'm an idiot. This was one of the best bridge glue jobs I've ever done. Minimal squeeze out that was easily cleaned up, the beautiful finish went right up to the bridge and even though I don't rabbet the bridge it lloked like it went under it with no distortion or any problems.

Yes I was proud of myself.

Then I decided to wax the ebony bridge and in doing so my dang players fingernail made a cross grain scratch in the FP. I almost smashed everything in the shop, deleted my OLF account and promised to never build another guitar again.

Now that that's over I need to learn how to FP with the bridge on. I thought about taking the bridge off last night. Glued on with HHG, not a big deal really but why not give it a try first?

I tried the pointy edge of the eraser trick, making a nose in the mouse pad rubber, and just jamming the muneca up against it hard and everything seems to make it worse.

And how in the world can you pull straight glazing strokes with the bridge on?

Frustrating.
Author:  doncaparker [ Mon Jul 22, 2019 1:14 pm ]
Post subject:  Re: Tips for French Polishing with the bridge on?
It ain't easy, and while I've done it, I can't vouch for the results. I had to do it for reasons that are similar to yours; the top finish just wasn't right, and I needed to redo it after I did a great glue job on the bridge.

Have you subscribed to the Tom Bills Art of Lutherie website? The French Polishing videos on there are great. I think he has some good advice about finishing along the edge of the fingerboard that can be useful in your situation.

I think an important factor is to work fairly dry. Of course, that's the secret to French Polishing, right? Work with a drier pad than you think is needed?

Good luck!
Author:  Bryan Bear [ Mon Jul 22, 2019 1:23 pm ]
Post subject:  Re: Tips for French Polishing with the bridge on?
I've never done it and I'm sure I'm not telling you anything you don't know. . . but sometimes frustrations sets in and you need a reminder.

You have your build of shellac already so you don't need to be adding much shellac. Resist the temptation to work too wet and too much. Just like doing a full french polish if you spend too much time in a problem area you make it worse.

You might try to go to the art store and see if you can pick some of these up.
https://www.amazon.com/US-Art-Supply-Bl ... B01MCYP511

the "paper felt" could probably hold up mostly dry with alcohol or alcohol and shellac and allow you to get the point in there to work the surface over and move the finish surface around a bit.
Author:  Bryan Bear [ Mon Jul 22, 2019 1:24 pm ]
Post subject:  Re: Tips for French Polishing with the bridge on?
Don posted while I was typing and said it better than I did. Dryer than you think you need and short sessions so it doesn't get too soft.
Author:  jfmckenna [ Mon Jul 22, 2019 1:49 pm ]
Post subject:  Re: Tips for French Polishing with the bridge on?
Yeah Dryer is a good tip. I think part of my problem is that I made a new mouse with the eraser which ment starting all over again basically. The same mouse I'd been using to do the whole guitar I had built up a French Polish relationship with and we were getting along just fine, if you know what I mean. I don't have problems with the FB edge as that runs along the grain, it's the cross grain swipes that are hard to deal with.
Author:  doncaparker [ Mon Jul 22, 2019 1:55 pm ]
Post subject:  Re: Tips for French Polishing with the bridge on?
I know the feeling! New pads need time to get gross, then they work. Do you keep a jar of old pads and alcohol? If so, just dig one out and repurpose it. The shape won’t be right, but maybe you can coax it. I would rather do that than try to get a new pad to work right.
Author:  Bryan Bear [ Mon Jul 22, 2019 2:02 pm ]
Post subject:  Re: Tips for French Polishing with the bridge on?
I know exactly what you mean.

You have enough build that it (hopefully) shouldn't matter if it is along the grain or across the grain as long as it is pretty dry. The eraser or the artists blending stumps should allow you to work the finish that is there with some pressure kind of like burnishing the surface that is already there. It is hard to explain but I usually finish off with a dry, mostly alcohol charged pad and strokes with a fair amount of pressure to get my shine. True. I do it with the grain but I feel like I could get away with any direction. You could do across the grain at the leading and trailing edges of the bridge then so some pull strokes from the bridge along the grain if you need to blend that in. Again, I have not done this so take that for what it is worth.

I would practice on the string side of the bridge since, once the strings go on, the eye won't notice imperfections as well. Hopefully I would develop a technique on that side and be able to get the other side to look pretty good.
Author:  Paul Micheletti [ Mon Jul 22, 2019 4:10 pm ]
Post subject:  Re: Tips for French Polishing with the bridge on?
Dry is the ticket. When I charge the almost dry pad with a few drops of shellac, I start to work far away from the bridge. Stay at least an inch away until the comet trail off the pad is evaporating very quickly. Then you can go into that last inch around the bridge without leaving streaks that won't go away. Use some oil in this process too since you are not building but are touching up the already protective finish.
Author:  DennisK [ Wed Jul 24, 2019 8:52 pm ]
Post subject:  Re: Tips for French Polishing with the bridge on?
Maybe heresy, but you could try sanding it with the first 3 micromesh grits (rust, green, black) and then take a small square of muslin, fold it over twice, put some shellac and alcohol on it, and give the guitar however many swipes it takes to cover the bad area. I've gotten fed up with FP and do the entire finish wipe-on now, and that's how I get the final glossy surface. There's still a bit of technique to it (too much alcohol and it won't self-level, too much shellac and it will leave streaks), but overall very easy. If you screw up, try again the next day.
Author:  JSDenvir [ Sun Jul 28, 2019 12:42 pm ]
Post subject:  Re: Tips for French Polishing with the bridge on?
I’ve had some success not using a pad. Rather, I use the outer cover I’d normally use, along with a pointy pink eraser. I don’t put the cover over the point, but right to the edge of it. Place a drop of shellac and alcohol on the material, and then just make circles that bump against the bridge. You don’t leave shellac on the bridge because they never come in contact.

Steve
Author:  AndyB [ Mon Jul 29, 2019 4:13 pm ]
Post subject:  Re: Tips for French Polishing with the bridge on?
While french polish is a buildable finish, it is buildable at a imperceptible thickness, which is why it is the preferred method for classical instruments. That said I imagine your fingernail dented a soft top wood, but I'm guessing. How is more french polish going to help that?

My advice would be to take a micro pipette and wick a small amount of shellac into the crevice. Use a blond shellac so you don't create a color difference. Once it has dried, I would gently level. Then decide if you want to very sparingly do a bit of french polish over it just to get the same finish in that area, using the same shellac you used on the top. At this point the french polish part is nothing more than blending. Since you are not building finish at this point, I might be a bit lighter on the alcohol and make sure I have enough olive oil in play to not worsen your situation by having the muneca stick. Just enough to get a texture blend over the shellac drop fill. Good luck!
Author:  jfmckenna [ Mon Jul 29, 2019 6:04 pm ]
Post subject:  Re: Tips for French Polishing with the bridge on?
AndyB wrote:
While french polish is a buildable finish, it is buildable at a imperceptible thickness, which is why it is the preferred method for classical instruments. That said I imagine your fingernail dented a soft top wood, but I'm guessing. How is more french polish going to help that?

My advice would be to take a micro pipette and wick a small amount of shellac into the crevice. Use a blond shellac so you don't create a color difference. Once it has dried, I would gently level. Then decide if you want to very sparingly do a bit of french polish over it just to get the same finish in that area, using the same shellac you used on the top. At this point the french polish part is nothing more than blending. Since you are not building finish at this point, I might be a bit lighter on the alcohol and make sure I have enough olive oil in play to not worsen your situation by having the muneca stick. Just enough to get a texture blend over the shellac drop fill. Good luck!

Great suggestions. I actually went pretty thick, as French polish goes, on this guitar so the nail scratch was actually only finish deep. So I was able to sand it out. So far so good, or good enough, trying to build back the shine. I hope in about 3 more sessions I'll be done.
Author:  Pat Foster [ Tue Jul 30, 2019 10:02 am ]
Post subject:  Re: Tips for French Polishing with the bridge on?
Late to this party. My learning curve was to get away from concentrating on the bridge area, making the pattern of motions like the rest of the top as much as possible. Once I got out of my mind that I was "French polishing around the bridge," things improved significantly. Dry is good too, also avoid bumping up against the bridge, which squeezes shellac out of the muñeca, which makes it too wet in that spot on the top, which in turn either leaves a streaked/bumpy surface or dissolves what's already there.
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