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Does anyone have any experience with the U-Beaut hardened shellac. I know there was a past thread on the subject, but I haven't been able to find it.
Thanks, Wendy

There's threads here and here. You'll find plenty of opposing views, like with water based coatings. Personally, I use a version of the stuff all the time and have never had any problems. However, the Shines version that I use has always had the plasticiser in it and the special brew I have made does not contain the additive (a small amount of a slower evaporating alcohol) that extends the wet edge time. I use the hyper-speed azeotropic brew with acetone and never use oil. Most of the guitars pictured on my website have soundboards (at least) French polished with hard shellac. As with most finishing, and French polishing especially, technique is everything. It behaves a bit differently from "normal" French polish but is no harder to use, just different. Like using any other type of shellac, you get better at it the more you do.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

I plan on giving it a try on my current Selmer build. I have yet to try it. I was thinking of only using it as the last few FP sessions but I'll read up on technique first.

I used it on an instrument for the first time recently (curing now). It does behave a bit differently from my homebrewed spirit varnish that I normally french polish with. I can get it to build pretty fast but have a hard time getting a perfect finish straight from the pad as I do with the stuff I mix up (may have something to do with not using any oil in the process). But since it gets much harder I'm not too concerned about that: next week I plan to rub it out and buff it which i normally wouldn't do with a french polished finish.
I'm generally happy with my normal finish but since this is a steel string (I normally build classicals) I wanted something tougher.

If you're talking about building your finish with normal shellac then using it for the last few sessions, I wouldn't. It's my understanding that you never really want to put a harder finish over a softer one as that's a good way to get checking. I'd suggest (as the manufacturer does) just sealing with a wash coat of normal shellac then building your finish with the hard shellac.

Oh ok thanks for the advice. So are you saying that you would not even do a spirit session with this stuff because of the way it behaves?

I wonder if this could simple be treated like a brush on lacquer, just brush on several coats, let it cure, wet sand and buff?

Never tried the stuff but IF you go the brush route it might be better to treat it more like a traditional Spirit Varnish. Really thin it and apply a dozen or so coats. I don't see why it wouldn't work. . .

I'll restate a prior post on this subject. U-beaut is an excellent product but it does behave a little differently from the standard French Polish. I prefer a mix of 2/3 alcohol to 1/3 U-beaut. This ratio gives a very light blond, almost clear, finish. When applying the finish you can use the same technique as standard French Polish but there is no need to add any additional alcohol to the pad. I also prefer using Dr. Duck's instead of olive oil or baby oil for the simple reason that you need less of it to achieve excellent results. The number of sessions you need to apply the finish will depend on how nice you want the finish to look. It's been my experience that 20 is the minimum and I'm usually very satisfied at 30 sessions. One technique that works quite well is to switch to 1" felt block instead of soft wool for the last 3 - 4 sesions. Cover the felt block with soft cloth and apply the shellac directly to the cloth and a small drop of oil if needed. The stiffness of the felt will help soften any swirl marks and makes the final buffing process easier. A word of caution; U-beaut like all shellac finishes does not have the durability of nitro or polymer finishes. If you're building for a customer make sure they know that the finish will require at least a minimal amout of care. Of couse the upside is French Polish is fairly easy to repair.

Hmm...
A few things: First, a minor point, but I don't see how the mix ratio or "cut" has any bearing on the color of the finish.

Second, I've only used the product once and haven't experimented that much with it but the manufacturer advises against using any oil in the polishing process so I'd be a little concerned about that.

Third, my understanding is that after cured U-Beaut IS as tough as say a nitro finish. That's the advantage of using it. My first instrument using this product is currently curing so I don't have any first hand knowledge of its toughness, only what I've read. But if it is AT ALL as delicate as a normal shellac/spirit varnish finish I'll be severely disappointed. If it wasn't tougher then what would be the point of spending 3-4 times the money on it over mixing up your own finish (which, in my case, I actually prefer the look and smell of)?

And, finally, as far as being easy to repair, it is my understanding that the additives in "hardened shellac" that make it harder achieve this though facilitating crosslinking. That being the case, after curing it IS NOT repairable and is actually one of the disadvantages of using these products. Again, it's possible that I'm wrong but this is my understanding from reading about the product.

How long does it take to cure to that hardness? I've read that shellac takes a long time to fully cure; does the cross linking make U-Beaut cure faster than typical shellac.

Yes, the manufacturer's website says 20 days. I believe Mr. Gore has earlier stated that he buffs out after half that time.

Nice! Thank you, William.

I'm not sure how one can apply this finish without some oil component but I'll take your word for it. Just for reference, some time ago I contacted Neil Ellis, the U-beaut guru and , I believe, the guy who developed it, and asked what he recommended. His reply was that he prefered mineral or paraffin oil. Personnaly I prefer Dr. Duck's. I've finished at least 20 guitars with U-beaut and the oil component, for me at least, is essential.
As far as U-beaut being as durable as nitro; from my experience, it isn't, period. Don't get me wrong it's an excellent finish and certainly more durable than standard FP but it's still shellac.
Finally, it isn't difficult to repair, I've done it and the results were flawless.
Hope this helps.

Hard shellac was developed by Robert Rae of Shines (Sydney) and is marketed by U-beaut (Neil Ellis, Melbourne).

I never use oil with the hard shellac I use, so I assure you it can be done. As I said earlier, applying shellac is all about technique and the only "right" one is the one that works best for you. My shellac finishes, as far as I can tell, are on a par hardness-wise with nitro. Before I used the stuff on guitars I FP'd a kitchen work bench, which gets all the use/abuse most kitchen surfaces get. It's still going strong some 8 or so years later, which, on reflection, is probably better than nitro would have done. I just did a test: dropped a 2:1 mix of acetone and ethyl alcohol on the kitchen bench, left it for 20 seconds and wiped it off. Nothing happened. I wouldn't want to try that on a nitro finish!

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Wow Trevor thats good to know.

I've just buffed out a guitar with a hard shellac finished top and nitro finished back and sides. Sanding and buffing were done about 15 days after last application. To all intents and purposes, both finishes reacted exactly the same through the wet sanding and buffing stages. I can only tell the top is done in shellac by the smell of the sanding dust!

The gloss level is identical both sides. Here's some pics:


And, so it doesn't feel left out, here's a classical with a hard shellac finished top, just done.

If you don't want so much gloss, you don't have to have it. And, of course, you can finish directly "off the rag", if that suits you better.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Nice work Trevor - do you spray the hard shellac also?

Thanks, Tony.

I like to call my finishes "French Polished" when I use shellac (for me, that's the point, really - it's about the process), so I apply it with a fad.

_________________
Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au