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PostPosted: Sat Nov 19, 2005 3:42 am 
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Cocobolo
Cocobolo

Joined: Thu Jan 06, 2005 2:40 am
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Location: United States
I'm french polishing a guitar for the first time. One of the considerations that I always read is that french polish is easy to repair. Well, I need tips.

On one of the sides I have a drip that is about an inch long and a quarter inch wide at the top. I've just finished my 5th bodying session. Do I sand it out? Try to remove it with alcohol? Finish my bodying sessions and then deal with it? After I remove it, how do I repair that area? Any suggestions would be appreciated. Thanks.


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PostPosted: Sat Nov 19, 2005 3:51 am 
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Cocobolo
Cocobolo

Joined: Fri Jan 07, 2005 3:46 pm
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Location: Golden, Colorado
First name: Roger
Last Name: Labbe
Go ahead and sand it back. Use a fine paper, such as the Meguier's 1200 Unigrit, which is a superb paper. Don't try to just sand the drip, or you'll end up sanding divets into the polish around it. Just go ahead and knock it back, then repolish. Don't linger too long in that area, but just swipe in and out, stopping frequently to allow it to harden. If you spend too long in one area, you'll soften the polish below and end up with a gooey mess.

Try it, you'll see how easy it is. Ordinarily I'd say practice on scrap, but really, even if you mess this up you can still fix it. So you might as well learn how.

P.s. how did you end up with a drip? I assume you splashed some french polish from the bottle while charging your fad? If your fad is dripping, it's way to wet.

rlabbe38675.4948958333


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PostPosted: Sat Nov 19, 2005 5:43 am 
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Cocobolo
Cocobolo

Joined: Thu Jan 06, 2005 2:40 am
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Location: United States
Thanks. I'll give it a try.

I don't know how I got the drip. I don't think my fad is too wet. I think it must have happened when I was going around the edge of the guitar and sonehow squeezed the fad against the corner and something squeezed out??? I don't know.


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PostPosted: Mon Nov 21, 2005 5:19 am 
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Cocobolo
Cocobolo

Joined: Fri Jan 07, 2005 3:46 pm
Posts: 372
Location: Golden, Colorado
First name: Roger
Last Name: Labbe
While you didn't ask, let's diagnose that. There is no way a pad should ever be that wet if you are using appropiate techniques. Most of the techniques taught involve dripping shellac and alcohol into the pad. This can lead to trouble. I now much prefer the technique taught to me my Marshall Brune.

The Brune's don't bother with adding shellac and alcohol separately. All they do is put some shellac in an empty everclear bottle, then add alcohol to it until a single swipe on spruce does not lay down any color.

Then, to charge the fad, take the cheesecloth or whatever you use for a fill, put it on top of the mouth of the bottle, and VERY briefly turn the bottle over so the shellac contacts the cheesecloth. It's something under a second total time, but more than just a glancing splash. Then, take the cheesecloth off the mouth, and press it against the side of the bottle. If you got it too wet, this operation will squeeze out the extra. Then put the cover back on, and continue polishing. This guarantees that you will never end up with a pad that is too wet, and is quite a bit easier trying to count drops of shellac and alcohol.



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PostPosted: Mon Nov 21, 2005 5:33 am 
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Cocobolo
Cocobolo

Joined: Thu Jan 06, 2005 2:40 am
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Location: United States
You've raised a couple of questions in my mind. First, however, I sanded out the drips (found a second one)and re-bodied them and it looks like they were never there. Thanks for the advice.

To your point, I've been following the Milburn article and I wondered why they add alcohol to the fad after the shellac is added. Isn't that, in effect making a 2# cut weaker? Is the added alcohol allowing for the shellac in the pad to bind with the shellac that is already present? If you don't add any additional alcohol, what cut are you using? Still 2#?

Back to my problem, when I apply the shellac, I see the "cloud" the Milburn article talks about repeatedly and there doesn't seem to be any standing shellac on the guitar, so it seemed to me (who doesn't know any better) that the right amount was being placed, other than the two drips which seems to indicate differently. I'm hoping, since both drips came from the top and dripped down the side that I had a momentary lapse and is not an indication of complete ineptitude. Guess we'll know when we are finished.

Thanks again.


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PostPosted: Mon Nov 21, 2005 6:17 am 
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Old Growth Brazilian
Old Growth Brazilian

Joined: Tue Dec 28, 2004 1:56 am
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Location: United States
If the drip is at the edge formed by the top and side (naturally) the odds are that you got a bit firm with the pad at the edges. That said one of keys is the inner pad. I always load my inner pad and allow it to set up 24 hours before using it. This way the shellac is not layed down too wet. The trick is for the newly applied shellac and alcohol to melt the shellac in the inner pad just enough to allow it to be layed down. When you add shellac and alcohol to the pad you are just adding enough to replenish that which has been extracted, 3-5 drops. If you tap your pad on a sheet of white paper it should leave a finger print looking mark and not a solid wet spot. If it leaves a solid un broken wet spot, the pad is too wet.MichaelP38677.5962962963


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PostPosted: Mon Nov 21, 2005 8:44 am 
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Cocobolo
Cocobolo

Joined: Thu Jan 06, 2005 2:40 am
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Location: United States
You might be right with me getting too firm at the edge. Would the right analogy be more of a plane taking off as opposed to dropping off a cliff?

Do I also understand that you lod your pad with shellac, let it sit out for a day and then use it? I've got a lot to learn on this.


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PostPosted: Mon Nov 21, 2005 9:53 am 
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Old Growth Brazilian
Old Growth Brazilian

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Location: United States
After I work each edge I always work the vertical surface very lightly and quickly after comlpleting the horizontial surface or as I notice a drip. Dont reload, just use a light quick body motion. This will evenly spread any drips of shellac if you have any. Also after the first three body sessions I spirits each surface directly after each body session, and do so untill the completed. This by its nature will help keep all surfaces leveled out and eliminate all or near all level sanding with proper care.


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PostPosted: Tue Nov 22, 2005 12:28 am 
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Cocobolo
Cocobolo

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Location: United States
Even after spiriting, are you able to see swirls in the finish. When I got through with the 5th bodying session, the surface was not overly rough but when the light glanced off the surface, you could see swirls throughout. Will they be removed when I sand?


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PostPosted: Tue Nov 22, 2005 1:34 am 
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Old Growth Brazilian
Old Growth Brazilian

Joined: Tue Dec 28, 2004 1:56 am
Posts: 10707
Location: United States
[QUOTE=SStallings] Even after spiriting, are you able to see swirls in the finish. When I got through with the 5th bodying session, the surface was not overly rough but when the light glanced off the surface, you could see swirls throughout. Will they be removed when I sand?[/QUOTE]

I don’t look at refraction properties during bodying. At that stage I am concerned only with building a mostly level film. Bodying is not glazing or polishing. The intent of bodying is to build the thickness of the film. By firmly and quickly spiriting after each body session you will reduce the required glazing time. How intense you spirit between body sessions will determine how level your film is during the body sessions. With all that said, don't over due the exerted pressure on the pad during spiriting. You do not want the the pad to drag or stick at all. The motion sould be like stroping a razor on a leather strop.

If your film is rough as in uneven and ridged then there is something in your technique that is amiss. The spiriting between body sessions if done in a firm glide on and glide off manner should knock down all high points and level out the film, but it will be the glazing that brings out the luster and total levelness in the film.




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PostPosted: Tue Nov 22, 2005 8:39 am 
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Cocobolo
Cocobolo

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Location: United States
So far, from everything you've said, I'm somewhat encouraged with where I am. The surface was pretty smooth which I was pleased with and was hoping the swirls were not a major defect. I plan to be close to finishing it over the T-giving weekend so we'll see where I am then. Thanks again.


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PostPosted: Tue Nov 22, 2005 8:51 am 
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Old Growth Brazilian
Old Growth Brazilian

Joined: Tue Dec 28, 2004 1:56 am
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Location: United States
The only issue I can think of that would be bad news for you is if what you are calling swirl marks are contamiante left by the pad or traped between sessions. I have faith that is not the case.

Be aware that when you start glazing the change will not happen instantly. I keep an incondesent work light at a position so that I can see the reflection of the pulb on my work surface as I am glazing. If you do thiis You will notice the reflection of the bulb will slowly start to come into clearer focus as you proceed. When you have a mirror clear reflection you will know you there.


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PostPosted: Tue Nov 22, 2005 9:07 am 
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Old Growth Brazilian
Old Growth Brazilian

Joined: Tue Dec 28, 2004 1:56 am
Posts: 10707
Location: United States
A second thought or insight as it were, is to take a small area and spend about 10-15 min glazing that area. if the swirls disapear in that area then all is fine. If they don't, well then you have some work to do. If you need to add more bodying over this glazed area for some unknown reason that is no problem. So this may be a good confidence builder for you. You might want to give it a try.


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PostPosted: Wed Nov 23, 2005 4:56 am 
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Cocobolo
Cocobolo

Joined: Thu Jan 06, 2005 2:40 am
Posts: 148
Location: United States
full report this weekend, I hope


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