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PostPosted: Sat Mar 02, 2013 12:45 pm 
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Has anyone experienced this? French polishing on rosewood and I've got about 8 bodying sessions done (2 body 1 stiff etc) and I've got several areas that just don't want to get shiny.

The wood was freshly and well sanded.

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PostPosted: Sat Mar 02, 2013 1:45 pm 
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Just a thought-are you perhaps overworking these areas? When FPing things can be a little counter-intuitive and sometimes less is more.

I think it's natural to want to work areas more that don't seem as shiny/don't seem to be building as fast but, in fact, you end up pulling finish up and being counter productive. Similarly, I find that I can actually build a finish faster with a cut that's on the thinner side (something like 1-1 1/2 lb).


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PostPosted: Sat Mar 02, 2013 2:30 pm 
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Due to variances in wood and many other factors this tends to happen sometimes at first, 8 sessions is not that many. Keep polishing the entire top evenly as mentioned, don't concentrate on the spots. They will gradually fill in and the finish will build. Also what type of pore fill did you use? sometimes that can contribute to conditions like this.

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PostPosted: Sat Mar 02, 2013 3:47 pm 
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I once had a small spot on a burl rosette that shellac didn't want to stick to, and I remember a thread a long time ago where someone else had similar problems. I'd polish and nothing would build there, and then I'd wipe some on and it would just bead off to the surrounding area. In my case, and I think the other person's case too, the solution was to carefully place drops of shellac on the offending area and let it dry, until it had a coating to start building on top of.

But it's also possible you just haven't done enough bodying yet. Can you post a photo?


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PostPosted: Sat Mar 02, 2013 4:50 pm 
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French polishing is strange that way. The best way to fix a small area is to ignore it while working the areas around it. Eventually it is fixed and you weren't even working on it.

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PostPosted: Sat Mar 02, 2013 5:57 pm 
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Let it rest. Don't do anything for a couple days. This happened to me on occasion when I was learning to FP. I think it's because one are isn't quite dry, and when you go over it again it lifts off the soft shellac. Additionally, you'll tend to give this area more attention, making it worse.

The pad is likely a bit too wet. Remember you should see a good cloud as you move along. It's the most important thing.


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PostPosted: Mon Mar 04, 2013 12:13 pm 
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Thanks everybody. You guys are awesome! I couldn't believe after that many sessions there was no build on those spots and I WAS hitting those places extra hard. I just rubbed some shellac over those areas a few times with my finger (probably unkosher) then carried on as normal. Back in business! (btw I did not bother to pore fill because every time I French polish it takes me so long that all the pores get filled in with shellac!)

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PostPosted: Mon Mar 04, 2013 1:35 pm 
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I had rough patches too, but mostly on the spruce, not the rosewood. I just keep going and eventually (after a LONG time) those rough patches get filled in. But you also have to check that the shellac isn't being pulled off... if its dragging or sticking then something's getting pulled off. With the correct speed of movement and pattern the pad should be gliding smoothly with a slight cloud trail behind it.

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PostPosted: Tue Mar 05, 2013 5:15 pm 
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Filippo Morelli wrote:
Is your pad sticking at all? My pad has healthy shellac, a bit of alcohol (just enough cut a bit) and enough oil that it moves smoothly. My experience is that it's hard to pull off shellac from the surface. If you have too much shellac in your muneca, the pad will invariably load up and stick on the surface. There is no substitute to, continue working, experimenting and connecting in your head the relationship of "wax on wax off" with the amount of oil, shellac and alcohol, the state of your muneca, et cetera. Epiphanies are local, unfortunately.

Filippo

It has'nt been sticking. I tend to use a generous amount of shellac but trying to cut back. Have not used oil yet, but perhaps getting stickier the more build I have. In the past only used a bit of olive. Seems like a lot of people singing walnut's praise?

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PostPosted: Tue Mar 05, 2013 5:51 pm 
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Quote:
It has'nt been sticking. I tend to use a generous amount of shellac but trying to cut back. Have not used oil yet, but perhaps getting stickier the more build I have.


Geez. No wonder. Use a couple drops of oil. Where did this FP without oil thing come from??

I prefer plain olive oil. Walnut has a tendency to dry on the piece unless you finish it all in one session. This can lead to alligatoring and other issues if not carefully spirited off. I only use walnut for the initial surface flooding and grain filling if doing furniture in the traditional manner.


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PostPosted: Tue Mar 05, 2013 6:01 pm 
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olive oil.

On my small( like Millburn size) muneca, I use about 4-6 drops shellac, 2-3 matho, and 1 oil each time I recharge, and always make sure to blot the muneca, so it's all uniformly distributed. I've done a few FP projects, and am sreiously contemplating re-doing my first guitar, as practice is what gets you over the line in FP


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PostPosted: Tue Mar 05, 2013 9:21 pm 
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I use about a half drop of oil per load - no more. I have switched to olive oil too - used to use Walnut oil. It worked fine, but it tried to become part of the finish. Olive oil works it's way to the top if you don't spirit it all off.

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