Official Luthiers Forum!

I wound up doing an extensive rebuild to a guitar that had a partial Royal Lac finish on it. I figured it was best to go ahead and complete the finish with Royal Lac. The end result is something I am quite happy with and it did not require spray equipment or a power buffer (both of which I have). I thought there may be some builders on here who are looking for a hand applied finish that gives good results so here goes:
Previously I tried to brush the Royal Lac on with a flowing brush as the total finish. Pretty much a disaster. It sets very fast and leaves ridges where one brush stroke overlaps with another. What worked really well for me was to do a hybrid brushing/French polishing technique.
Mostly the wood was sealed with shellac but some spots were sealed with Seal Lac. The first step after sealing is to get adequate thickness of film on the guitar. For this I used a good cow hair brush and tried to flow on the smoothest possible coats. It is possible to build up a number of coats in one day. If a huge ridge or brush stroke was visible I knocked it off with some 320 grit gold paper and sometimes a razor scraper. Once it seemed like there was enough finish I proceeded to level the entire guitar with 320 grit paper. Royal Lac sands very well with very little gumming of the paper. If I happened to sand through in spots I just hit this with a little shellac and brushed more Royal Lac over that. Once the guitar was completely leveled the next step is to bring out the gloss. Here's where the French polishing comes in. The goal is to fill in all the sanding scratches and the padding motion guarantees that no ridges will be built up. I found that Royal Lac takes more oil than shellac. I use walnut oil. I've tried olive oil but am really used to the feel of walnut oil so that's what I stick with. Once your pad, Royal Lac, alcohol, and lubricating oil start working well you will get the characteristic "clouds" that you see with traditional shellac French polishing. The clouds do not flash off exactly as with shellac but you can clearly see your strokes as the pad leaves the area you just polished. Royal Lac builds more quickly than shellac, which is a positive thing. It did not take long at all to fill in the scratches and build up a smooth surface
The next day I spirited off the oil with straight alcohol and a pad with a smooth cotton cover. For this I used straight strokes and followed the grain. The path of the pad becomes less and less obvious as more of the oil comes to the surface. You can see the oil being transferred to the cover as a dark smudge so switch to a clean part of the cover to remove more oil. The straight alcohol coupled with the fine fabric cover also melts the padding marks very slightly and further levels the surface.
I let it dry for about 4 days and lightly sanded with dry 2500 grit sandpaper in spots to remove any dust specs or pad marks. The final gloss is achieved with Novus #2 polishing compound and an old tee shirt.
The end result is you can clearly see that the finish is hand applied. It does not have the monolithic appearance of a modern poly finish, although you could probably get there if you level sanded with 2500 grit to remove all gloss and then polished with Novus. I don't mind seeing a bit of texture in the surface. Most shellac French polishes retain a bit of irregularity in the shine which in many ways is more appealing to my eye than a glass-like surface.
I am still not thrilled with the odor of Royal Lac. I used a chemical respirator during application. It is interesting that Seal Lac does not smell bad at all.
Hand application of Royal Lac seems to be the best bet judging from the problems some have reported with spraying. I don't know of another finish that is as durable that can be applied with a minimum amount of specialized equipment or a spray room.

_________________
Stay with the happy people.
--Reynolds Large

Did you notice any issues blending the royal lac in areas that were not finished or you sanded through? I ask because I am finishing a re-built guitar (new top and bindings, new fingerboard) and there are areas where i went through the royal lac to the wood below.

My experience with the finish is exactly as you describe!

Cool, I've really been wanting to give this stuff a try.

What are the issues with spraying?

It sprays easily. Wet sand and buff as usual.

_________________
Steve Smith
"Music is what feelings sound like"

Not as of yet. Time will tell I guess. I re-sealed with shellac on the sand-through areas on the notion that shellac sticks to just about everything and is recommended as a first coater for Royal Lac. If I decide to use this again I think I might do all the sealing and leveling with Seal Coat.

As for spraying, do a search for Tim McKnight's experiences with Royal Lac. I ran into him at the Memphis show and we spoke at length about his problems with Royal Lac. It is hard to say where the problem had its genesis but the amount of extra work required by Tim to re-do the guitars is enough to make me never consider spraying it.

_________________
Stay with the happy people.
--Reynolds Large

I tried brushing Royal Lac, but soon switched to padding it on. I like French polishing, anyway. The padding went much, much better than the brushing. I posted about this sometime in the last two years.

The Royal Lac feels thicker and gummier than normal shellac as you are padding it on. You soon adapt. I did not notice the smell being that bad.

I think the issue with spraying was that a special formulation of Royal Lac was put together by Vijay specifically for spraying and it did not uniformly work well. Lots of posts on this.

Tim McKnight was spraying a special formulation which did not work out. I sprayed the standard formulation and it works just fine.

_________________
Steve Smith
"Music is what feelings sound like"

Didn't he also put his guitars in and out of the freezer a bunch of times?

I think that was some test panels.

_________________
Steve Smith
"Music is what feelings sound like"