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French Polish - Getting that Final Gloss
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Author:  BruceH [ Sat Feb 17, 2007 1:50 pm ]
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I'm taking my second stab at french polishing. My first didn't turn out too bad, but I need to take it up a notch and it's been a year since I did the last one.

I'm currently having trouble with getting a final level finish. I had leveled the finish with straight long strokes with 80% alcohol 20% shellac in my pad. Then I lightly sanded with 1000 grit and buffed. Not good - I can see that I didn't get level enough.

So, what's your technique for the final leveling? Do you do it all with the pad and alcohol, or do you sand to get there, or what?

Thanks.
Author:  Michael Lloyd [ Sat Feb 17, 2007 3:08 pm ]
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Here's a web site which details French polishing. I follow this process pretty much to the letter. Especially having the right quality of solution in the pad during the different steps.

“Smack the loaded muneca against the back of your hand to help distribute the shellac/alcohol mix. Use a sheet of typing paper to blot the muneca. A wet blot means too much mixture. No blot at all means it's too dry. A water mark print means that the muneca is correctly loaded.”

I use a 2 pound cut (4 oz shellac to 16 oz alcohol) like yourself. So I would say the mix is right. I have also found that after 4 coats, I tend to let it dry 24 hours before each of the next coats. I find it easier to work if allowed to harden between applications.   

Regards,
Author:  Martin Turner [ Sat Feb 17, 2007 4:27 pm ]
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I started out using a 2lb cut for body coats and about a 1.5lb cut for glaze coats. Ive since gone to a lighter cut (less than 1lb cut) and put on more body coats and no glaze coats. I cut back every 4-5 body sessions with 1200 grade W and D and do a final poilsh with Meguiars No 7 Mirror glaze. My technique is a combination of methods from the Milburn Bros tutorial and Robbie O'B's finishing DVD.

I initially pore filled rosewood with pumice using the Milburn tutorial but found it tedious and the results not that good. I now pore fill with a 50/50 Zpoxy/ethanol mix which get sanded back to bare wood.
Author:  jhowell [ Sun Feb 18, 2007 2:55 am ]
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My technique is pretty much like Martin's. I use 1000 grit wet or dry to cut back and level and because I'm using olive oil as a lubricant for FP, I'll leave a few pieces of the 1000 grit soaking in a small pan of olive oil to use during this process. The paper backing on the automotive and paper seems to hold up for a week or so in the oil. I do a cleanup with naphtha and then go back to polishing.

Warning: A geetar covered in olive oil is a tad slippery. One has to be really focused here or...
Author:  jfrench [ Sun Feb 18, 2007 4:36 am ]
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For the final shine, the finish should be level enough to sand out with 1500 grit paper. I do this dry, no lubricant, etc - then buff it out on the power buffer with 3m compounds. It produces a realy nice shine and its easy.
Author:  BruceH [ Sun Feb 18, 2007 8:12 am ]
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Thanks for the help, guys. I've been using the Milburn instructions, kind of. I need to go back and look at my technique. I think I'm not using enough oil and am laying the shellac on too wet.
Author:  Colin S [ Sun Feb 18, 2007 9:34 am ]
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You see this is where I have a problem. To me French polish is one of those finishes that never ever has that abrasive stuff rubbed all over it. I never 'level sand' and never buff. I feel that if you build thinly enough and spirit off with sufficient pressure regularly and then do a thorough job on the glazing at the end then that should be it. To me the final glazing is the last process, and my finishes are just as I want them. Oh, I have satinned it with OOOO wire wool.

If you need to do lots of levelling then look to the earlier processes.

Colin
Author:  JJ Donohue [ Sun Feb 18, 2007 9:48 am ]
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Colin...I don't see a "problem". If the guys who prefer a shiny surface get it with abrasive leveling and you get the surface you prefer with your method then isn't everyone satisfied?
Author:  BruceH [ Sun Feb 18, 2007 11:01 am ]
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JJ - I assume that you use abrasive leveling also?

Author:  JJ Donohue [ Sun Feb 18, 2007 1:03 pm ]
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Bruce...I just completed my 4th...each one became better and I did it faster as my experience grew and my methods improved. I followed Robbie's method for the latest efforts and have had better success. That method includes an occasional leveling with 1200 grit.
This is a real feel and tactile process and I believe you just have to pay your dues. I also know that if I could observe the more experienced FP finisher, I would significantly shorten the learning process.

Colin is right about getting the technique down so that less mechanical leveling is required. He's done far more than most of us and has acquired the knack. As I acquire a better feel for the amount and cut of shellac on the pad, the pressure required as well as knowing when to use oil and when and how to spirit I may get to the point that I won't need to level with sandpaper. Until then, I'll use the tools and methods available to reach the endpoint that I'm seeking.
Author:  BruceH [ Sun Feb 18, 2007 3:13 pm ]
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Thanks JJ, I figured it was a dues-paying kind of thing, but I can always hope.

Back at it....
Author:  Joel [ Sun Feb 18, 2007 3:23 pm ]
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JJ and other guru's, how much pressure is good? I haven't tried FP yet but I want to do it on my first build. I gained quite a bit of experience spit polishing my boots in basic training years ago. Can spit polishing boots and French Polishing guitars be equated? At least in terms of how hard you rub?
Author:  JJ Donohue [ Sun Feb 18, 2007 4:31 pm ]
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Colin and Michael Payne (currently on the injured reserved list) are the resident gurus. In my opinion, the touch of the pad is the element that can only be learned by experience but I can give some basic principles for you to consider:

1) Use a 1# cut of shellac
2) Use less rather than more shellac in the pad
3) When the pad is fully charged start off with a very light touch...look for the tell-tale vapor trail behind the moving pad.
4) As the pad dries out apply more force to the pad
5) When the pad starts to stick with your strokes, apply a small drop of oil and go in circular motions. Finish with straight strokes.
6) Think of an airplane doing touch and go landings at a shallow angle. That's the trajectory of the pad that you want to mimic as it lays down shellac across the surface.
7) When you se a buildup of oil, so a spiriting session with ETOH only on the pad
8)You may have to occasionally level with 1200 or so to smooth out the surface.

If you screw up, you can always correct it with spiriting and/or bodying sessions.

Author:  Martin Turner [ Sun Feb 18, 2007 9:51 pm ]
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JJ's advice is sound.

I'm a complete beginner at French polishing still but what I have found is that it definitely takes a bit of time to get used to the feel of the pad as the shellac goes on. You just get to know when the shellac isnt going on right or the pad is starting to get a bit tacky and its time for a bit of oil.
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