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 Post subject: Re: French Polishing
PostPosted: Sat Jan 04, 2020 1:00 pm 
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Koa
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Simon, Agreed about straight FP on soundboards and steel string players. I should have mentioned I use 2 coats of Uralkyd 500 after sealing and levelling with blonde shellac padded on rather generously with cheesecloth. After a week of drying/curing I then French polish over the levelled oil varnish to achieve the final gloss. The main shortcoming for FP on the entire instrument is the dulling that happens where the player's body comes into contact, like the upper bout on the back bass side. With modern blonde shellac these areas invariably turn dull and unsightly. I have not seen this damage on the older guitars I mentioned. This has me following the path that the old style heat polymerized shellac has benefits.
As for Royal Lac: lots of guys love it but I don't. It did not mesh well with my technique. YMMV. It seems to devour any oil that is used in traditional FP and the oil stays in the film. Spiriting off is largely ineffective. The smell is objectionable to me, kind of a weird styrene smell. I'm sure others will chip in and say they love the smell. And, the completely non-reversible, insoluble characteristic is not a plus in my book. Search previous threads for some of the nightmares other members have experienced with it. That's not to say that the problems were entirely Royal Lac's fault. Only that if problems arise due to errors, whether from the user or the product itself, you are out of luck.

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 Post subject: Re: French Polishing
PostPosted: Sat Jan 04, 2020 1:04 pm 
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Koa
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HI Tom,
Is there a reason why you put shellac over the varnish? Is that for repairability reasons? Regardless, that method were certainly give you greater durability than a straight FP.


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 Post subject: Re: French Polishing
PostPosted: Sat Jan 04, 2020 1:10 pm 
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Koa
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meddlingfool wrote:
Are you hand sanding or power sanding?


Is this question directed at me, Ed? With the rotisserie setup, the oil varnish lays down so smooth that level sanding goes pretty quickly. I do it all by hand because of the control that affords me.

However, if you are doing a satin finish (I seem to recall you all do a lot of satin but I might be wrong). I could honestly see you not even needing to do any level sanding at all - except for a bit of spot leveling. You have to scuff sand between coats but that's easily done by hand in a matter of minutes. A satin oil varnish with a rotisserie setup would be extremely easy.


Last edited by Toonces on Sat Jan 04, 2020 2:09 pm, edited 1 time in total.


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 Post subject: Re: French Polishing
PostPosted: Sat Jan 04, 2020 1:16 pm 
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Brazilian Rosewood
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Toonces wrote:
meddlingfool wrote:
Are you hand sanding or power sanding?


Is this question directed at me, Ed? With the rotisserie setup, the oil varnish lays down so smooth that level sanding goes pretty quickly. I do it all by hand because of the control that affords me.

However, if you are doing a satin finish. I could honestly see you not even needing to do any level sanding at all - except for a bit of spot leveling. You have to scuff sand between coats but that's easily done by hand in a matter of minutes.


Yes, it was, thanks...


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 Post subject: Re: French Polishing
PostPosted: Sat Jan 04, 2020 2:28 pm 
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Brazilian Rosewood
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I apply Royal lack in the same manor of traditional FP with a pad, alcohol and walnut oil. It's definitely different but doable.


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 Post subject: Re: French Polishing
PostPosted: Sat Jan 04, 2020 2:31 pm 
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Brazilian Rosewood
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Post Cat or regular?


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 Post subject: Re: French Polishing
PostPosted: Sat Jan 04, 2020 2:33 pm 
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Koa
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Simon, I find it easier to achieve a gloss with FP rather than buffing oil varnish. And yes, should the soundboard need retouching this is easily done with FP. Original Deft is a great drop filler for dents. Scrape level and polish over.

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 Post subject: Re: French Polishing
PostPosted: Sat Jan 04, 2020 2:48 pm 
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Koa
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Thanks, Tom. That does make sense.


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 Post subject: Re: French Polishing
PostPosted: Sat Jan 04, 2020 2:54 pm 
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Koa
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I'm feeling this discussion having recently started using oil varnish as well.

I like it because I can brush it (can't spray at my home shop) and it looks amazing. Everything Simon says is true, it is slow, the brushing isn't too bad (especially with the rotisserie) but isn't mindless like spraying can be. Worrying about witness lines is no one's idea of stress free sanding either. I'm sanding between coats with abranet dry, each time with a finer grit. Sand with 1000 before the final brushed coat. Level sanding after that is almost non-existant, it is just polish sanding. The material self levels REALLY well.

I was using Pratt and Lambert 38 but they are losers and discontinued it :( :(.

I tested the Ace varnish that Bruce uses and it looked fine but was "bubblier" to brush. I'm testing Old Masters super varnish now. The Sutherland Welles 500 finish has been described as "ultra hard" which I don't like the sound of but others are using it with great satisfaction. If Simone is happy with it I imagine it is great :)

There are pioneers in this world- For steel string guitars I think Kim Walker, Bruce Sexauer, Al Carruth and (especially for me) Laurent Brondel have done the work of making it acceptable in the past 10-20 years. They were doing it before Collings and Bourgeois. I don't know what Kim uses but Laurent used Epifanes and his guitars look great. The Epifanes is very yellow, which I like the look of on many things. Al uses the same product as Simon I believe, having switched from Behlens Rockhard when they changed the formulation. I chose a Soya varnish (P&L, Old Masters) because it is slightly less yellow out of the can and not overly hard (I want it to be flexible).

GluBoost worked perfectly for drop fills and nicks after assembly. Was kind of shocked how well it worked actually!

I have used Endurovar with success (as has Laurent years ago). It is a nice finish. I do not love the brown-ish tinged amber color it leaves over the spruce but it isn't that bad. I find the oil varnish easier to brush/level but I never tried the Endurovar with the rotisserie and heat I use on the oil. In a pinch I would use it again without concern. When I did use it I still put Waterlox down first (a semi-varnish itself) to activate the wood. I did not have issues with adhesion.

I am trying to have the varnish be the first thing to touch the wood, everywhere. I am using epoxy over that but not trying to leave an epoxy film. The epoxy goes over the varnish seal coat and gets cut back. If you go through the next seal coat will leave a blotch free surface. Ideally, the epoxy is only trapped in the pores. I don't have a good reason for this, I just hate epoxy :)

I would prefer to french polish every guitar but agree that it is softer than people expect. I like the look of a played FP guitar. The nicks and marks look like love, not abuse. Not everyone agrees, however. It is an unfortunate reality that people buying and selling 10K +/- guitars worry about resale value and keeping a guitar pristine is important.

And, important to say: the enthusiasm in having initial success with a new finish is contagious. It is tempting to think you have found the perfect material/schedule/solution etc.... Even those who have used oil varnish for years have complaints and have many many more years of experience and knowledge of the finish than I do, having used it just a handful of times. So far so good though.

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 Post subject: Re: French Polishing
PostPosted: Sat Jan 04, 2020 6:57 pm 
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meddlingfool wrote:
I recently saw back a well used guitar that I sprayed with PC royal-Lac, which supposedly has additives to overcome the lack of water/sweat/alcohol that regular FP users comment on. It still looked great.

However, I was completely unable to either pad it on or FP, but I know of at least one person who is able at least to FPmthe tops with it.

Any of you regular FP folks tried it?


Ed, the guitar I showed above was FP'd with Royal Lac but I used the regular version, not the pre cat.

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 Post subject: Re: French Polishing
PostPosted: Sat Jan 04, 2020 7:11 pm 
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Koa
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Hi Burton,
I agree .. the rotisserie makes a world of difference. The varnish self levels so easily that I'm doing my final sanding/leveling with P2000 grit paper. I strongly recommend the paper by Kovax - sold in the US by Eagle Abrasive. It's a game changer, IMO.

I wanted to try the P&L 38 because it was supposed to be a bit lighter in color - this is my only complaint about oil varnish in general. A micro thin spit coat of epoxy makes a noticeable difference in how dark the wood gets, especially with spruce - straight oil varnish on the wood tends to darken the wood too much for my tastes. The Murdock varnish is still a relatively "soft" finish - especially compared to something like urethane or polyester. The alkyd resin is urethane modified which makes it a bit harder than some other resins but again, still pretty soft. Give it a try - you might like it and I follow up in a few months and see if you've found a good brand to replace the Pratt & Lambert.


For anyone trying oil varnish, the key thing is to make sure you have some sort of sealcoat with oily woods. Problems getting the finish to dry will cause you to go mad. But if you do the proper prep work, you won't have a problem.

It is by no means a perfect finish (no such thing) but it is one of the best solutions out there, IMO -- and the best thing is that it can be brushed on and isn't dangerous to work with.



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 Post subject: Re: French Polishing
PostPosted: Sat Jan 04, 2020 9:05 pm 
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Brazilian Rosewood
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wow.


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 Post subject: Re: French Polishing
PostPosted: Sat Jan 04, 2020 11:02 pm 
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Brazilian Rosewood
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meddlingfool wrote:
Post Cat or regular?

Oh was that a question for me? My cat likes to hang out in the shop but she's not alloud in there when I am french polishing, otherwise I have no idea :D

I'll have to look at the can. As far as I know it's was the regular stuff LMI sold and according to the directions was to be padded or brushed on not sprayed.


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 Post subject: Re: French Polishing
PostPosted: Sun Jan 05, 2020 9:48 am 
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Brazilian Rosewood
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What type of rotisserie are people using? Is it something appropriated from the barbi?


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 Post subject: Re: French Polishing
PostPosted: Sun Jan 05, 2020 11:35 am 
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Koa
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I made a setup with a DC motor and controller and pillow blocks. It is spinning at low rpms, maybe 10-15? Easy to adjust with the controller. The "arm" is a metal bar with tapped holes. My dummy neck extension bolts onto the bar. I have it spinning over a little shop heater and it does a good job of slightly accelerating the varnish curing while avoiding hot spots.

I remembered too that Pat Foster was using Oil varnish too. I reached out when I was starting to experiment with it, he was very helpful :)

To the original question- I really like the Tom Bills tutorial and completely agree that it should be downloadable! It is very expensive to pay for each month. I subscribed for a few months while I practiced and once I felt I had soaked up enough I made some serious notes and suspended my subscription. I would gladly pay for the subscription if available, it is so well done.

I liked the buttons better than the flakes. They seemed a bit harder overall and I liked the colors. I did not add walnut oil to the shellac mixture, instead I used it as you normally would use olive oil, as a lubricant. I was fascinated with the method of using activated carbon to dilute the color. I couldn't get it to work as well as he seemed to but I didn't put a lot of time into it.

I've never been able to pumice fill and not have it sink after a few months. It doesn't sink much, but enough to be visible in the right light. I don't mind that look at all, it makes it look like a well done thin finish. On the top especially I think seeing the grain of the spruce is nice. If I wanted a longer term smoother finish I would do an epoxy fill.

I had very good luck sanding with the abranet discs (by hand) between coats. After that there is 3M product called Trizact- in 3000 and 5000 grits I saw someone recommend. Those worked great for the last sanding before glazing and hand buffing. That gave me my best FP finish.

What really helped me was doing real test panels, something I rarely feel like I have time for :shock: I was able to scratch them and attempt repairs, work out blotching issues, feel how much sanding it really took to break through etc.... Being able to go too far gave me much more confidence when I worked on the actual guitar. I know you are supposed to always do that...... but I imagine most of us don't take the time. It was REALLY helpful.

Simon- first, apologies for typing Simone in my post! It is my daughters name and I did it on instinct. also, I will try the 500 varnish. I have to do test panels for the Old masters so it shouldn't take much to do the other varnish at the same time. I worry that all the true oil varnishes will disappear so it would be nice to have something that seems like it may stick around longer. Nice to work with a product others are using too :) I'll let you know how it goes.

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 Post subject: Re: French Polishing
PostPosted: Mon Jan 20, 2020 2:38 am 
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I pore fill with pumice (4F - Fine) and very thin shellac - rubbing the pumice into the grain, let it dry and then start building coats. I have built coats w/o filling, it just takes more coat to get to a glassy finish. It might be in my head but the pumice seems to create a more 3d relief in the grain to my eye when I fill with it.



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 Post subject: Re: French Polishing
PostPosted: Mon Jan 20, 2020 10:55 am 
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Brazilian Rosewood
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gxs wrote:
I pore fill with pumice (4F - Fine) and very thin shellac - rubbing the pumice into the grain, let it dry and then start building coats. I have built coats w/o filling, it just takes more coat to get to a glassy finish. It might be in my head but the pumice seems to create a more 3d relief in the grain to my eye when I fill with it.



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I think that's because with pumice you are also essentially sanding the guitar and polishing it out. The pumice is a very very fine abrasive. I've noticed the same thing when I used to use pumice. I just don't have the patience for it any more.


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