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French Polishing woes (one spot won't build)
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Author:  Bryan Bear [ Tue Nov 23, 2021 2:55 pm ]
Post subject:  French Polishing woes (one spot won't build)
Have any of you ever experienced this?

I am starting french polish and just starting to get noticeable build. I am using Royal-lac over Z-poxy fill. I have done this same regimen on 4 other guitars. with the only difference being I am using orange Royal-Lac instead of super blond. I noticed that one half of the edge at the tail is not building. It wasn't inherently obvious until I caught it in just the right light. The section is about an inch wide from binding edge into the back wood and maybe 4 inches long (along the edge).

Right about now, you are getting ready to type a request for a picture. I tried, I can not get a photo to show what it looks like. You have to look at it from just the right angle to see it but it doesn't show up in the picture.

I have tried the two approaches that usually work (for me) when there is a problem area. The first is to ignore it and keep polishing trying not to hit that area as aggressively until it starts to even out. The second is to give the area some extra attention to build a bit more finish before proceeding as normal. Neither seems to make any difference.

The only thing I can think of is that since this is on the edge, I may have sanded through the undercoat of regular shellac I seal with before starting the Royal- lac french polish. Still, I would expect the Royal-lac to stick anyway.

Any other causes you all can think of for this?
Author:  SteveSmith [ Tue Nov 23, 2021 3:21 pm ]
Post subject:  French Polishing woes (one spot won't build)
Not sure what to suggest but can say I haven’t had this issue although I seal with shellac over Aquacoat.
Author:  jfmckenna [ Tue Nov 23, 2021 4:05 pm ]
Post subject:  Re: French Polishing woes (one spot won't build)
I have seen stuff like this before too. And yeah usually I ignore it and it builds up anyway. IT could be a contaminate though so you may and to hit it with some sand paper, probably no less than 400 grit. And if you use oil to FP then you can use oil to lube the sand paper. Then just lightly clean up the problem area and build it back up again. Don't forget that spot will be thinner now so when doing the FP hit that spot more often then the rest.
Author:  bobgramann [ Tue Nov 23, 2021 4:40 pm ]
Post subject:  Re: French Polishing woes (one spot won't build)
I thought there was always one spot when french polishing. And then, the difference gets worse because I want to put more shellac on that spot—hitting it too often dissolves what was there rather than building with new. So, for me, the solution is to wait a day or two and then add to just that spot (usually without rubbing) for a few coats (usually spread over days) until it starts to even out. Using 1 pound cut instead of two lets it build faster because the alcohol evaporates more quickly allowing less time between coats. Then, sanding like jf suggests to even things out before continuing with the normal process.

I usually go far longer than I expected to, arbitrarily decide I’m done, let it harden for many days, and then level sand and polish like it were a lacquer finish. It seems like french polishing is never really done.
Author:  Bryan Bear [ Tue Nov 23, 2021 4:56 pm ]
Post subject:  Re: French Polishing woes (one spot won't build)
Well I’ll be darned! I solved the problem and it was simple. I wiped two coats of regular shellac over the area. Once dry, I started FPing again. Viola, it is building wonderfully now. Even though wiping shellac across the surface really screwed up the surface quality that was starting to develop, it is already starting to blend back in.

I didn’t really think I had sanded through the regular shellac in that spot. Especially since the shape of the edges of the area did not look like sand through. I think what probably happened was I lifted it off in the very early stages of adding Royal-lac. The sides of my pad were probably a little too hot (too much alcohol) and I slowly lifted it off without realizing it. We’ve all, at one time or another fallen into the trap where you are removing finish instead of putting it on.

I probably should have tried that before posting.

The real lesson here is that Royal-lac really does need a good sealer coat(s) of regular shellac. I know Veejay recommends that but it always felt a little silly to me. I believe it now.
Author:  SteveSmith [ Tue Nov 23, 2021 4:59 pm ]
Post subject:  Re: French Polishing woes (one spot won't build)
Glad you solved it. I’ll keep that one in mind.
Author:  Bryan Bear [ Tue Nov 23, 2021 5:07 pm ]
Post subject:  Re: French Polishing woes (one spot won't build)
Bob, I didn't see your post when I was typing my response.

It would appear that in this case, there was no need to wait days. I wiped on two coats of (about) 1 pound cut shellac with only allowing enough time for it to dry to the touch between.

I started working the area with my pad charged with straight 2 pound cut Royal-lac (no extra drops of alcohol) and it immediately started to build fairly quickly.

To your point, had I been more patient, and started adding back less aggressively, I likely could have avoided sanding all together. I went with the aggressive approach because I wanted to know if the solution would work or not. So now, the area around the bad spot is a little "lumpy" from getting too much shellac, too thick, too soon. I'll sand that down with olive oil after a few sessions of doing the whole body to even it out. I can usually do an FP job without sanding unless I have to do a repair. I'm not good enough or maybe not patient enough to do a repair without needing to even things out.

The first time I did FP with Royal-lac, I built too fast and got a little lumpy. I was amazed at how easily sanding with a little olive oil and 1000 grit paper fixed it up. I'm glad I learned that because that came in really handy when I needed to repair serious damage to the finish of my last guitar.
Author:  Bryan Bear [ Tue Nov 23, 2021 5:10 pm ]
Post subject:  Re: French Polishing woes (one spot won't build)
SteveSmith wrote:
Glad you solved it. I’ll keep that one in mind.


Yeah, I'll keep that in mind too and be more mindful when I am just starting to cover the shellac base coat. Good lesson learned.

I tend to think of Royal-lac as just being shellac until it does whatever it does after 30 days. I mean, I know it goes on a little differently but I underestimated how different it is.
Author:  Bryan Bear [ Tue Nov 23, 2021 5:27 pm ]
Post subject:  Re: French Polishing woes (one spot won't build)
jfmckenna wrote:
. Don't forget that spot will be thinner now so when doing the FP hit that spot more often then the rest.


I wanted to highlight this comment for anyone reading this that is new to FP because it is an important point. There is a difference between concentrating on an area and hitting an area more often. When you want to build a spot, there is a temptation to keep working it and that is usually the worst thing to do. The way to get more shellac on there is to come back to it more often than the other parts during the whole session but allowing it plenty of time to flash off the extra alcohol.
Author:  SteveSmith [ Tue Nov 23, 2021 5:29 pm ]
Post subject:  Re: French Polishing woes (one spot won't build)
I've been using 600 when I get lumps or whatever, I'll try 1000 next time. Glad you mentioned that.
Author:  Bryan Bear [ Tue Nov 23, 2021 5:41 pm ]
Post subject:  Re: French Polishing woes (one spot won't build)
Good, maybe this thread will end up having value after all.
Author:  SteveSmith [ Tue Nov 23, 2021 5:55 pm ]
Post subject:  Re: French Polishing woes (one spot won't build)
Bryan Bear wrote:
Good, maybe this thread will end up having value after all.

Of course! It’s all the little things adding up that help you get really good at doing something.
Author:  jfmckenna [ Tue Nov 23, 2021 11:03 pm ]
Post subject:  Re: French Polishing woes (one spot won't build)
That's the beauty of FP technique, well knock on wood anyway, but so far I've been able to fix every mistake somehow.

I have recently started using Royal Lac and while it's similar in a lot of ways it's just different enough to add into a new learning curve. One thing I noticed with it is that with normal FP shellac I am happy with the finish right off the rag, so to speak. But with RL it does require a cure time followed by buffing out. Spiriting doesn't have the same effect. But after that it looks fantastic.
Author:  doncaparker [ Tue Nov 23, 2021 11:20 pm ]
Post subject:  Re: French Polishing woes (one spot won't build)
The whole 1 lb. cut thing was a real advancement for me when I learned it in a Robbie O’Brien course not long ago. It makes a huge difference in the shellac’s ability to build instead of strip what was just put down. That problem had dogged me prior to taking the course.
Author:  jfmckenna [ Tue Nov 23, 2021 11:53 pm ]
Post subject:  Re: French Polishing woes (one spot won't build)
I have to say that I never once measured the 'pound cut' of shellac. I don't even really know what it means. I just followed the steps from, I think Millburn, or some such tutorial online where they said, add shellac to a Ball Jar then fill it with alcohol to about here. That typically gets me some thick juice. Then I like to use a brush and brush on 3 or 4 coats, level back then start to FP. Then I use the alcohol that I cleaned the brush with as a thinner and for a glaze coat.

But yeah, it's that alcohol flare that you need to see behind the pad that makes all the build up layers. What I do in each session is start with whatever cut of shellac I have and add that to the pad then some oil drops on the guitar and polish out till the flare dies down then I add alcohol which rekindles the session and when that dies down more alcohol, more alcohol till I spirit off in straight strokes. OF course sometimes more shellac too but the idea is to start heavy then thin out.

That's another thing about FP that I actually love about it. It's like Jazz improv or something. Basically you can teach someone how YOU do it but ultimately they are going to riff on their own and figure it out. It's a very personal thing and it in fact changes over time. I got my start with the Milburn tutorial and it's a great introduction. Much later I found Pablo Requena's YouTube tutorial which is also fantastic.
Author:  DennisK [ Wed Nov 24, 2021 1:43 am ]
Post subject:  Re: French Polishing woes (one spot won't build)
jfmckenna wrote:
It's a very personal thing and it in fact changes over time.

More like every time I do it gaah Once in a blue moon it will actually work and I try to memorize exactly what I did and how the pad feels, but it never does work the same way again. I usually give up and revert to simple wipe-on after a great deal of struggle.

Hopefully someday I'll be able to do it reliably. Proper FP really is beautiful on scraped corduroy texture.
Author:  SteveSmith [ Wed Nov 24, 2021 7:14 am ]
Post subject:  Re: French Polishing woes (one spot won't build)
I’ve also found I need to do a final buff on a Royal Lac FP finish although it still looks pretty good right off the fad. I like to wait at least a month before buffing.
Author:  jfmckenna [ Wed Nov 24, 2021 8:17 am ]
Post subject:  Re: French Polishing woes (one spot won't build)
DennisK wrote:
jfmckenna wrote:
It's a very personal thing and it in fact changes over time.

More like every time I do it gaah


Sometimes even on the very next day! Sometimes the same day! I'd swear that a slight change in temperature or RH makes the pad behave differently.
Author:  Bryan Bear [ Wed Nov 24, 2021 9:02 am ]
Post subject:  Re: French Polishing woes (one spot won't build)
A agree that FP is a constantly changing moving target as conditions change your technique changes a little bit too. The jazz comparison is a good one. I also think about it like driving a stick shift.

Driving and traffic conditions are constantly changing in small ways and you make subconscious adjustments to what you are doing. In it’s most basic form, you balance the application of throttle with the release of the clutch, you pullback on throttle (just enough) and apply the clutch (just enough) then shift to the next gear and time your release of the clutch and re application of the throttle. Pretty simple. But when you first learn to do it, the car bounces and learches, sometimes you aren’t in the best gear for what you are doing. Sometimes you are on a hill and you don’t adjust well when starting off.

Eventually, your brain starts to make the adjustments in the background and things smooth out considerably. The worst thing you can do at that point is try to analyze what you are doing. You’ll start thinking again and lose the natural rhythm. After a long time of doing it, you get beyond just doing it smoothly and start really being in control of what is going on. You realize that in certain conditions you can use the throttle to synchronize your shift and sometimes you don’t even need the clutch. At this point, it is so natural that you can start thinking about it again and it doesn’t mess you up.

With FP, I am at the stage where I am beginning to drive (mostly) smoothly but get myself into trouble when I try to think too much. I look forward to the day when I can really be in control of what I’m doing.

I will say that with Royal-lac, I have gotten a god finish right off the rag with no buffing but I don’t really know how I got there. I hope to someday be able to get there consistently and intentionally.

Like JF, I don’t really measure pound cut. I know that Royal-lac is 2 pound cut in the can but I’ve never measured beyond that. I mix alcohol and shellac on the pad with eyedroppers to the mix that is working for me at the time. Towards the end of the session, it gets more alcohol than shellac. I think I am kind of “spiriting off” at that point.
Author:  banjopicks [ Wed Nov 24, 2021 9:12 am ]
Post subject:  Re: French Polishing woes (one spot won't build)
I have a question for you French polishers, how do you work on all sides without ruining the finish when you flip it over? I'm pretty sure this will be my next finish method. I hate compressors.
Author:  bobgramann [ Wed Nov 24, 2021 9:28 am ]
Post subject:  Re: French Polishing woes (one spot won't build)
As for polishing all sides without harming the reverse side: I start on one side, then go to the back. When I finish the back, if the first side is hard enough, I do the other side. When the back is hard enough, I do the top. Usually, I don’t have to wait very long (never more than a few minutes) to be able to put a side down on the carpet.

A 2 pound cut, 2 pounds of flakes in a gallon of alcohol, reduces to 2 ounces of flakes in 8 ounces of alcohol. I make a bottle of this 2 pound cut, squirt some into another bottle and dilute it with an equal amount of alcohol to get some 1 pound cut. The one pound cut hardens much faster.
Author:  doncaparker [ Wed Nov 24, 2021 10:06 am ]
Post subject:  Re: French Polishing woes (one spot won't build)
banjopicks wrote:
I have a question for you French polishers, how do you work on all sides without ruining the finish when you flip it over? I'm pretty sure this will be my next finish method. I hate compressors.


There are a couple of ways. One way is to work out a stand/jig that allows you to firmly (and I mean really firmly) hold the guitar with just a stem sticking out of the body from the neck attachment area. This assumes separate finishing of the neck and body. If they are already connected, just put the neck in a sturdy vise.

Another way is to just wait for the finish to firm up enough before you flip to finish the opposite surface, and use something really soft and smooth underneath so it won't print on the finish. This is another reason to use a thinner cut, like a 1 lb. cut. It hardens way faster than a 2 lb. cut.
Author:  SteveSmith [ Wed Nov 24, 2021 10:28 am ]
Post subject:  French Polishing woes (one spot won't build)
I work with the body on a towel. Again, I’m using Royal Lac, with Everclear and walnut oil. I do one side then turn it top down and do the back. By the time I’m done the first side is dry enough to turn the body and do the other side. Finally I lay the body on the back and do the top. After that I do the neck working from the headstock down to the heel.

Usually I’ll go back to the body and do another session. All together the two sessions take me about 30 min.

When I come back to it, which is often later in the day, I go over everything and check for dust nibs or other problems. Anything I find gets fixed before I move on. Then I do two more sessions. So on most days I can comfortably do 4 sessions.
Author:  jfmckenna [ Wed Nov 24, 2021 10:57 am ]
Post subject:  Re: French Polishing woes (one spot won't build)
My strategy is to do the top first then the 'drive side,' the side that faces the player. Then I might go back to the top and drive side again. Then hang the guitar for 30 minutes and then do the back and the non drive side in the same manor. Then it hangs for an hour and I repeat that session.
Author:  jfmckenna [ Wed Nov 24, 2021 10:59 am ]
Post subject:  Re: French Polishing woes (one spot won't build)
bobgramann wrote:

A 2 pound cut, 2 pounds of flakes in a gallon of alcohol, reduces to 2 ounces of flakes in 8 ounces of alcohol. I make a bottle of this 2 pound cut, squirt some into another bottle and dilute it with an equal amount of alcohol to get some 1 pound cut. The one pound cut hardens much faster.


I think I will try that on my next one just so I know what a 2lb cut feels and looks like.
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