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| Author: | Blain [ Sun Apr 11, 2010 12:32 am ] |
| Post subject: | Re: French polish questions |
I would recommend reading the Milburn French Polish instructions found here: http://www.milburnguitars.com/fpbannerframes.html Also if you search the archives or maybe even the OLF tutorials, I know Michael Payne has put in a lot of information on French Polishing as well. As for the Bridge...I usually tape off the area that the bridge will go. I'm sure some don't tape and then scrape that area, and others I'm sure will even do it with the bridge on. No right or wrong on this really. |
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| Author: | Peter J [ Sun Apr 11, 2010 8:24 am ] |
| Post subject: | Re: French polish questions |
Fillipo, Like Blain I also polish with the bridge off and with a piece of 3M painters tape where the bridge will locate. I carefully trim the tape about 1 mm. smaller than the actual footprint of the bridge and relieve the edges of the bridge contact surface to allow for as good a completed finished surface as possible around the edges of the bridge once it is glued in place. J Michael Thames has posted a 4 part french polish tutorial on youtube that complements the Millburn and Michael Payne information. You might want to review it just to see the differences in technique. http://www.youtube.com/user/JMichaelTha ... sGTJlLACYg French polishing is definitely a practiced and acquired skill. The more you do the easier and better your technique and the outcome will be. |
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| Author: | letseatpaste [ Sun Apr 11, 2010 8:35 am ] |
| Post subject: | Re: French polish questions |
I'd check out Robbie O'Brien's finishing DVD. I don't actually own it, but Robbie and I were in the Brune FP class at the same time and from what I understand that's the method he teaches in the DVD. It's pretty easy and straightforward. I haven't done much FP since the class, but I'm planning on buying the dvd as a refresher. Even after taking the class, the Milburn tutorial seemed confusing to me. Obviously a lot of people have made good use of it, but it just seemed overly complicated. (edit: I also had the same thoughts about the Fernandez FP video). |
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| Author: | Chris Paulick [ Sun Apr 11, 2010 9:46 am ] |
| Post subject: | Re: French polish questions |
I find Robbie's DVD is handy to have for sure. I used his method of FP combined with others to shellac my last build and then shot nitro over it. I'm going to try that Eraser trick of Michael's on the next one. |
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| Author: | WaddyThomson [ Sun Apr 11, 2010 9:59 am ] |
| Post subject: | Re: French polish questions |
I French polish with the bridge on and the neck on. It is not a big issue. You just have to make a small muneca that you can shape into a point to get into the tight spots. If you are careful, working in circles (I can't do figure 8's  ) you can get right up to the bridge. Then, you can Stiff off, cross grain, and glaze cross grain at the bridge's long edges. It may not be perfect, but it works fine. Same is true at the neck if it is built in.
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| Author: | Eric Reid [ Sun Apr 11, 2010 12:34 pm ] |
| Post subject: | Re: French polish questions |
My two cents: read everything you can find. Tage Frid's description in his "Shaping, veneering and Finishing" volume for Fine Woodworking has a lot of good information in it. His method probably comes closer to what I do than anything else I've seen. Two more cents: take the time to learn to pore fill with pumice before you resort to other pore fills. It is a hand skill. You can get a little frustrated when you're beginning, but when you get the knack, it really works. I like to think that a pumice pore fill sounds better. Maybe I'm imagining that, but I'm not imagining its practicality. With pumice you can fill any void on any wood at any stage of the process. I do finishing work for a number of builders, and I do a lot of french polish repair work. I use pumice to fill pores, fingernail scratches, porosities in the rosette, gaps in the purfling, even dents and wallows can be smoothed with pumice. I'll make it six cents: I finish with the bridge on, with the bridge off, with tape on the bridge area, and with a bare top. I work with whatever method the builder prefers, and obviously on repair work, the bridge is usually on. My preference? Bridge off, no tape. Obviously that's the easy way, but it's also how I do it when I'm the one gluing the bridge on. |
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| Author: | DennisK [ Sun Apr 11, 2010 1:07 pm ] |
| Post subject: | Re: French polish questions |
Eric Reid wrote: With pumice you can fill any void on any wood at any stage of the process. I do finishing work for a number of builders, and I do a lot of french polish repair work. I use pumice to fill pores, fingernail scratches, porosities in the rosette, gaps in the purfling, even dents and wallows can smoothed with pumice. If you're feeling energetic, I would love to see a video of pumice filling. Especially on rosettes and purfling gaps. Pretty much all the FP videos on youtube skip over the pumicing stage, or show very little of it, and my attempts thus far have been pretty iffy. If I try to follow the Millburn directions, all that seems to happen is that the base shellac layer clumps up into little "rolls", like if you rub your hands together while they're a little dirty. They don't really stick in the pores, and then usually fall off the edge of a small test piece, and I have to brush on a new base coat and try again. But then if I put a lot of pumice and alcohol in the pad, and scrub around one spot, it seems to work better. Still get some rolls at first, but they seem to dissolve a bit, and if I keep going until it dries out and starts to spread pumice visibly on the surface, then it gets some dried in the pores (and wears through my muneca cover pretty quick). But then there's pumice all over the surface, and I'm not sure how to get rid of it without dissolving and wiping away everything in the pores too... Oh well, I haven't put much effort into it thus far. Surely it will start to make more sense after more attempts. |
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| Author: | Eric Reid [ Sun Apr 11, 2010 5:26 pm ] |
| Post subject: | Re: French polish questions |
Dennis, I'd love to post a video, but I'm still struggling to learn how to do that. There's no substitute for lots of practice in French polishing, but maybe I can steer things in the right direction a little bit. You can dust pumice onto the surface with a pounce bag, you can dust it on the pad, you can sprinkle it on the roving inside the pad, you can dip the pad in a pile of pumice, you can dip the pad in a mixture of pumice and very thin shellac. I've used, and use all of these methods. the trick is in moving the pad across the surface. Err on the side of rapid motion, small amounts of pumice, and 3-5 minutes dry time between passes. I make 2" circles across the surface of one side, then the back, then the other side, then repeat. If you press too hard with a wet pad, or circle too long in one place, or use too much shellac, you'll get the build up you were having problems with. If this happens, you can always let it dry for 30 minutes, and sand it back. With practice, you'll learn to remove build-up with a fresh cover on the pad, but when you're beginning, you'll probably just smear it around. Make sure that each pass of the pad thoroughly wets any dry pumice on the surface, or you'll end up with light colored pores. Use lots of alcohol, and just a whisper of shellac. If shellac begins to build up on the surface before the pores are filled, you can end up trapping air in the pores that will bubble up later, and leave craters in your work. No fun. The first time you are successful, you'll be amazed at the amount of time you spent pore filling. With more practice, you'll be able to put on a lot more pumice in the early stages without getting build-up. When Everything is working right, it's enjoyable work. I've done plenty of spray finishing too (don't anymore), and I much prefer French polishing. |
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| Author: | DennisK [ Sun Apr 11, 2010 6:27 pm ] |
| Post subject: | Re: French polish questions |
Thanks Eric! That helps a lot. Sounds like I had too thick of a base shellac coat, too much pressure, too much pumice, not enough drying time between passes, and maybe not enough alcohol either. I have always read that you should keep the pumice quantity to a minimum, but it was always seeming to run out. Probably the pressure was my main problem there, forcing the pumice directly into the pores, rather than fluffing up wood fibers with it and gently sliding them in. Hopefully it will go much more smoothly now on my next practice run 
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