Official Luthiers Forum!

My update on a 5-years old post has somewhat "reactivated" the post. I posted that I had used water to level sand Royal Lac and the finish failed beginning two years and continuing progressively for five years. It was checking and wrinkling. Vijay, the chemist and owner of Royal Lac, reported to me that he has since learned from other reported finish failures to him that using water to level sand between coats will cause the product to fail.

I liked applying the product but, obviously, am now leery of it.

1. Who has used Royal Lac?
2. How old is your oldest finished guitar?
3. Have you had any finish failure(s)? If so, at what age?
4. What was your method details if it failed?
5. What was your method details if your finish is, say, 4 years old and has held up well?

I would actually consider using it again if there is enough experience with guitars several years old with similar methods of application.

What is your experience?

Ed, The little size 5 I posted in the other thread is just 4 years old this month. This one was FP, what sanding there was I did dry. Finish is still good, it's redwood so the usual dings, photo below.

I had fails with spraying but didn't do it right. My FP finishes are still good.

_________________
Steve Smith
"Music is what feelings sound like"

I've only done one, and it was done with the post cat. I tried to pad it on, total fail. So I resorted to using a preval sprayer in the back yard and hanging it on the washing line, just like the pros do, lol..

I did three coats the first day. Thick, gopping, run filled coats, because the preval sprayed the rather thick shellac very poorly. 2-3 hours between coats. Leveled dry with 320 next day. It's my feeling that if I'd been very careful leveling with a finer grit, I could have buffed out the 3 coats.

Did 3 more coats next day. Was hoping to get it show ready, hence the post cat as I was counting on the 72 hour cure time. Ran out of time and it hung unleveled about three months. Leveled by hand with 800'and up. Buff out was very difficult, it seemed a hard, hard finish. Took 45 minutes to do just the peg head face with my 3/4 hp Caldwell buffer. Did the rest on an old Larrivee industrial strength buffer and it worked a treat.

Guitar is probably 2/12 years old now, I just saw it at Christmas and it's doing just fine, even with the thick thick sprayed on coats...

I have had no product failures

My oldest finish is almost 5 years on a mahogany ukulele, Used both seal-lac padded original Royal Lac.

I used gluboost fit and finish to pore fill back sides and just seal lac to pore fill the top. I spent a few days filling the top applying and sanding back the seal lac.
After the pore fill I sealed the back and sides with a few coats of seal lac as well. In one day padded on 4- 6 coats of Royal Lac at least an hour in between. The next morning I dry sanded with 600 grit sand paper. I noticed I still had a few binding gaps, So I filled and leveled those with CA. Padded on 6 coats of Royal lac. The next morning I leveled with 600 grit sand paper added 6 more coats and hung to cure. I did not level sand but I did finish up on the buffer.







I did a few padded Royal lac instruments and then switched to the post cat Royal Lac. I had good luck from the start. I spray with a qualspray QS-125WB using a 1 mm tip. I find I need to clean the gun between each spray session or gunk grows on the tip. Not a big deal I empty the remaining product and spray some alcohol through the gun.

The only failure for me was my own prep where I left some spots of aqua coat on the surface on one of the sides on a guitar I sprayed with post cat Royal Lac, and the blotchyness under the finish bugged me. There is no fixing a Royal-lac finish to a new appearance (I tried) so I striped it down with hardware bought stripper (many applications as Royal Lac is hard after it cure). I refinished that guitar using Silvertip epoxy. sealed with 2 lb shellac and three days of four or five coats and hour and a half apart. I sprayed at about 2-3 mils wet coat. I will apply 4 or 5 coats a day, level in the morning. If I can level the finish without issue, I will spray 4 more coats and call the guitar done. If I had any issues like the need to drop fill or I sanded through the finish, I will repeat the above process. I let the sprayed guitar sit for about a month wet sanded up through a series of sandpaper grit 600 - 1200 and buffed. That is the guitar I posted in the other thread.

Precat Royal Lac

_________________
http://www.Harvestmoonguitars.com

1. Who has used Royal Lac?

Hand raised.

2. How old is your oldest finished guitar?

About 5 years old.

3. Have you had any finish failure(s)? If so, at what age?

No failures.

4. What was your method details if it failed?

Not applicable.

5. What was your method details if your finish is, say, 4 years old and has held up well?

I pore filled that particular guitar with Timbermate. I first tried to brush on Seal-Lac, but I didn't like the way it looked (too many brush strokes showing; lots of sanding would have had to happen), so I switched to French Polishing on both the Seal-Lac and the Royal-Lac after that. Dry sanding and wet sanding with olive oil every so often along the way to level things out. This was all with regular RL, not post cat. I waited the recommended cure time, and did some hand buffing. Worked out great.

If application failures can be included in this list then here goes:
Like others, padding the finish on was a nightmare. It did not flow out, dried very quickly, and lap marks were very visible.
Conventional French polishing with a smidge of oil did not work for me either. I found Royal Lac very "hungry" for oil and it disappeared into the finish. Spiriting out was ineffectual.
After lots of futzing around I managed to get a requinto finished by FP and Royal Lac. Since I have not heard anything about crazing, etc, I can only assume the film is OK.
A friend tried Royal Lac on his hammered dulcimers and applied it by many different methods, all of which yielded very bad results. He wound up sanding it off and applying lacquer.
Just another miracle finish in the dustbin, at least based on my experiences.
I know some guys love the stuff and more power to them.

_________________
Stay with the happy people.
--Reynolds Large

Royal Lac original (not prec-cat)six years ago. FP over z-poxy, still have the guitar, no failures.

_________________
formerly known around here as burbank
_________________

http://www.patfosterguitars.com

This OM is just finished. I did have a failure on my first application;however, the error was in my application (French polish). I sanded back to wood used 2 coats of seal lac then probably 12 coats of Royal Lac blond. The second time I used small circles, smaller pad, and more oil. I used olive oil and the finish came out nicely. I would sand with the oil as a lubricant. I read somewhere that wet sanding doesn’t work well with Royal Lac.

I should add that I used a pipette to drop no more than 6 drops of Royal Lac on the pad, 2 drops of Everclear, and one drop of olive oil....every time up until wash coat.


Sent from my iPhone using Tapatalk

I've only used it on 3 instruments now the oldest being 2 years old and it has no issues as far as I can tell. That is to say the guy who bought the guitar has not said anything about it anyway.

I filled with Starbond CA and then brush on the first 2 coats of RL.

Then use FP method and walnut oil mostly in straight strokes. Figure 8's and circles are ok with a freshly oiled mouse but it is definitely more sticky then traditional FP shellac.

For any high spots or cat hairs I will use a 320 grit wet dry paper with oil to sand it out.

I follow that up with a diluted mixture of RL and alcohol and glaze the instrument.

And that's it! No buffing or sanding.

Not full of all the application details but 5 years ago I finished two classical guitars with Royal Lac. Built together to be identical except for top bracing. EIR with WRC tops. ZPoxy fill on back and sides. Woods were from the same billets. I routinely use Zinnser Seal Coat shellac for sealing/protective coating purposes during a build so expect I did that on these two also ahead of final finish.

For final finish I used Royal Lac (not pre-cat) padded on in FP manner.

Both guitars went to the same customer. One needed some minor service recently and the customer brought in both for me to look at.

The top on one was uniformly and completely crazed - looked intentional. The customer was still very happy with the guitar and didn't mind the "antique" look and opted to keep it the way it is.

Bizarre part is two guitars finished one after the other with finish from the same can and one is perfect and the other has a crazed top (not sides, back or neck).

My build records aren't so detailed to include level of sanding, but I rarely wet sand so don't believe that was part of the problem but it's possible it could have been because I sometimes do limited wet sanding.

I liked the look and application of Royal Lac.

But there were things I didn't like. It was expensive compared to prepping shellac from de-waxed flakes. I ended up ordering 5 pints to make good use of expensive shipping. The short shelf life ended in me throwing out 3 unopened pints that turned to jello (probably out of the advertised shelf life, but not by a lot). I did not find Royal Lac to be noticeably more durable or scratch resistant than home brew shellac which was the primary purpose I gave it a try. When I finish with padded/FP finishes I normally do back and sides together then tops separately.

I don't mean to be negative about a product that obviously works well for lots of folks. I also suspect I could have made it work better with more effort and testing on my part.

I thought this experience was different enough to post but your mileage will vary.

_________________
Brian R, Wood Mechanic
N8ZED

Regarding durability (assuming no overt failures of the finish): I opine that a very thin French Polish finish is just not all that protective of the guitar, no matter what finish material is used. I mean, since it is applied via the French Polish technique, it will be either shellac or a modified version of shellac. Nobody French Polishes other finish materials. But my point is that the French Polish technique yields thin finishes (unless you really put effort into getting a lot of build). Thin finishes sound great, and they can look great, but they damage more easily, no matter what the material is, regular shellac or Royal Lac or some other modified version of shellac. Just my developing opinion.

I think you are right. I mean, when you get your shellac whether it's flakes or buttons the stuff is almost hard like glass. When you dissolve it in alcohol you are only doing that so that you can apply it as a finish, the alcohol evaporates out and you are left back with shellac. So it should be hard as can be but it does seem that because it's so thin it just does not appear that way. I wonder what damage to a shellac finish looks like under the microscope? My guess is that you would see conchoidal type fractures in the finish.

The reason I brought up durability and scratch resistance of RL was because it is part of the product description - "A finish that looks and feels like shellac but has the durability of any other synthetic finish." The product description of increased durability was what made me decide to try it and give it temporary preference over typical shellac mixes.

I didn't find RL to be noticeably more durable than other shellacs. Without that advantage I'd rather have the convenience of mixing my own.

I'm not sure the fragility of any shellac is necessarily a film thickness issue because even in heavy applications it tends to surface scratch fairly easily with a fingernail in my experience. Heavy application might protect the wood more put it doesn't make the finish surface less scratch resistance.

I like shellac and use it for a lot of wood projects inside and outside of luthiery. Shellac has a lot of properties going for it I think we all know.

_________________
Brian R, Wood Mechanic
N8ZED

I suspect the durability comparison is based around water and alcohol resistance more than scratch/ding resistance...

Thanks to all for your input. I appreciate it.

I used Royal Lac on 5 instruments about 4 years ago. It was a disaster. Looked ok for a month or two then turned into alligator skin. I had to remove all the finish on 4 instruments and refinish with lacquer. I kept the 5th and can say it's not very durable either. Whoever came up with this product should send me a couple grand for all the time it cost me. This stuff is a joke, a real bad joke. Not a professional finish.

_________________
Michael F Smith
Goat Rock Ukulele
http://goatrockukulele.com

You guys are scaring me now

Seems to me I've been warning about wet sanding any type of shellac based finish with water for many years here.....

_________________
Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

I like the Royal Lac, primarily because I don't have to spray it and it results in a nice thin finish. I had three failures with the RL that resulted in crazed finishes but, like any finish, you've got to learn how to apply it. I find durability to be similar to the target EM6000.

_________________
Steve Smith
"Music is what feelings sound like"

This is what happened to me, too. Alligator neck, checking body and headstock, etc. but it took longer than a couple of months to happen. A lot of cost and trouble and confidence loss to refinish that guitar for the client.

As I previously stated, the owner/inventor of the product said my level sanding with WATER between coats caused the failure. He learned of the failures due to people like us calling him. He did not know about the WATER problem with I did my finish and Robbie did his video

NOTE: Robbie's video still shows water level sanding between coats but flashes a blurb on the screen for a few seconds to wait for full cure, which would take months to finish of you waited 30 days between each series of coats and level sanding with water as shown on the video (nobody is going to wait that long). I think Robbie should delete that video. If someone misses the short blurb that flashes on the screen they are headed for major trouble

The purpose of starting this thread was to find out if WATER was indeed the only problem. I see that LMI is selling the product now which is a promising sign. When I used the product no guitar material suppliers were selling the Royal Lac.

Probably mentioned somewhere, I am assuming original Royal Lac. Was it padded on or sprayed? If sprayed what was the wet thickness that you sprayed.

As I mentioned I have not had any issues. I have never wet sanded with water until the finish cured. I have used mineral spirits as a lubricant while wet sanding between coats. I have sprayed post-cat product never the original. I also work in a humidity controlled environment. Even my spray room.

_________________
http://www.Harvestmoonguitars.com

I finished one instrument with RL several years ago and the finish did craze badly after a few months (but it was a give away for a friend's kid, made with some freebies that came with other wood orders so not the end of the world).
In my case I pore filled with egg whites, sealed with plain dewaxed shellac then used the expedited fp method, mixing with acetone (at the time, I had read a couple of accounts of people having good results with that).
Like others, I ended up doing mostly straight-line padding rather than my normal FP method because it was a bit stickier than regular shellac.

I don't believe I wet sanded between coats. More often than not, when doing FP, I don't need to sand at all. However, I couldn't get this stuff to act exactly like typical FP so I did wet sand at the end and buffed.
The finish built quickly and looked good...for a few months.

There are too many variable here for me to be sure what went wrong:
Could have been use of regular dewaxed shellac as sealer rather than seal-lack (though, at the time, I'd heard that was fine).
Could have been the addition of acetone and the quick build. I've had success with this with normal FP and, again, at the time had heard of success doing this with RL.
Or it could have been the wet sanding of the final finish.

I haven't revisited since but may at some point.