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I was wondering if anyone had any knowledge as to the relative durability/hardness of Behlens Rock Hard Varnish...how does it compare to Nitro, KTM-9, and the various catalyzed finishes when looking at it's ability to resist dents, scratches, etc...

Thanks,
Greg

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Gwaltney Guitars

I have used it on seven or eight guitars and like it a lot. It is at least as durable as Nitro, and much better than the KTM-9 I used on one guitar. I don't have any experience with the catalyzed finishes, so I can't compare. I really like the look because it turns spruce tops a great color, they look 50 years old. It buffs up to a nice shine, but it's not as glossy as nitro. I think it has a rich, mellow look but it doesn't have that wet look shine you can get with Nitro or Poly.

                   Peace, Paul

I don't think it's quite as hard as fresh nitro, but it is tougher. That is, it's easier to scratch or dent, but does not chip as badly. I'd expect the varnish to be reasonably stable over time, whereas nitro breaks down chemically, so that in fifty years or so the varnished surface should look a lot better.

If you want wet shine in varnish, try Pratt & Lambert 38 Gloss. This is the varnish that Velaquez is now using. He doesn't pore fill, just uses the varnish. I put it on my last guitar and the shine is deep and glossy - more like nitro than french polish. I was surprised and found I liked it better than my FP guitars. I had my girlfriend choose which she liked better (without my identifing what was what, or even why the comparison was being made), and she also chose the Pratt & Lambert. Brushes, and will come to a shine using just elbow grease.

BTW, Fine Woodworking has an article on varnishing where they used this varnish. Rubout is just with pumice, than rottenstone after sanding to 2000 wet. I used Mcguiers compounds, which also work very well.

The P&L H38 will also spray nicely when thinned with turpentine. Add Japan Drier to speed it up if desired.

Not quite a nitro/poly gloss level, but very nice indeed. I use it for all my non-instrument woodworking stuff and yes, have tried it on an instrument. It does shrink-back, so pore filling is recommended if you want it to look level in years to come.

Don't mean to hijack the thread, but those of you who have used P&L 38, how is it for witness lines? With Rockhard you have to be so careful not to go through the last coat when you do the final rub out. I have had to do additional coats on several guitars because even the smallest area where you go through the top coat to the coats below really shows up. I'll keep using varnish because I really like the look, but it would be nice to find a product that was a little easier to use.

                      Thanks, Paul

I was going to ask the same question Paul, I hope someone has some experience here.

Greg

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Gwaltney Guitars

I don't recall any witness lines, but then, I tend to apply wet on wet. And I spray, not brush.

By a quart and test on scrap....

I didn't get witness lines, but I have done exactly one guitar with it. I may have gotten lucky, but this was my first time varnishing. I also did like Mario, wet on wet.

When you say wet on wet, how long are you waiting between coats....were you brushing or spraying?

Thanks,
Greg

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Gwaltney Guitars

I don't really want to answer - I did *one* guitar - that does not put me in any position to offer advice. But basically, I recoat before the varnish is fully cured, about where it is merely thinking about still being tacky. You're going for a chemical bond, not a mechanical one. I was brushing, reduced about 10-15% with mineral spirits to improve flow out.

I don't know the long term consequences of this - this was done on a test mule that will never be sold to a customer. It was based on advice in the FWW article.