Official Luthiers Forum!

I've run out of warm weather for the outside spray booth and I need more coats on my guitar. Can I thin down the lacquer and apply with a brush?

_________________
A higher purpose for wood.
Rich Smith
Issaquah, WA

Hi Ricardo,

I haven't brushed lacquer but I know you can mix it with a retarder to slow the drying time in order to use a brush. Check with the manufacturer of the brand you are using.

Cal

_________________
Remember, there are no stupid questions, only stupid answers!

Simply thinning it will speed up the dry time because thinner is more volatile than lacquer. You can brush it if you use a lacquer retarder which will slow drying time and give it time to flow out. It's doable, but it's not a great experience.

What Jim said. Thinning it will cause it to dry quicker, making brush marks an even bigger problem. Adding retarder will work, but it will take a really long time to cure before buffing. It will also be off gassing some stuff that's bad for you while it's curing. Nitro makes me sick. Obviously when I spray one with Nitro I've got my respirator on, but I can't go back into my finishing building (without a respirator) for a week or so. Your best bet would be to find a local automotive painter that will let you use his spray booth. I finished guitars for years in the spray booth at an automotive dealers body shop before I added my spray room. You're welcome to come use my booth, but I'm ~3000 miles away

_________________
I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

I won't go easily or level well. And retarder keeps the lacquer soft for a long time.

_________________
Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I think I'll find a local fellow luthier who has an inside spray booth to finish the job. Thanks All!

_________________
A higher purpose for wood.
Rich Smith
Issaquah, WA

There are brushing lacquers available. I have a 1l can of it but haven't tried it out yet.

Watco brushing lacquer:
http://www.rustoleum.com/CBGProduct.asp?pid=48

_________________
Expectation is the source of all misery; comparison the thief of joy.
http://redrivercanoe.ca/

Brushing lacquers are more for furniture and woodwork than instruments. There is a difference. If this is your first guitar, it may be an acceptable finish but for true quality finishes you need to get the good stuff . I have been using Mowhawk and Behlen finishes for a few years. Shirwinn Williams also makes a fair lacquer.
Macfaddens I hear is back . I also use the vinyl sealers and try to keep all the same from the same company . I have found some compatibility issues mixing too many brands together. Finishing is not just about what you use but the technique that is used. Also it isn't about what you put on , but what you let on. The prep is so important , a bad prep won't get you a great finial finish. Get a good fill , that is as important as anything to get a nice level finish. You need a good build coat , and your level sanding has to be spot on. It is a lot of work and you may spend as much time on finishing as you did building.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I remember my dad talking about painting cars with lacquer on cold days, and he said he would heat a pan of water and set the quart of lacquer in it to warm up and it would spray and flow beautifully. Not sure what temp he got it to though.

Good to know! I'll leave my can for other projects.

Putting on a good finish IS a lot lot of work. Sometimes I feel like everyone puts more emphasis on the finish than the build. Sometimes I wish that perfect shine wasn't such a concern to so many people.

_________________
Expectation is the source of all misery; comparison the thief of joy.
http://redrivercanoe.ca/

I have not had good experiences with brushing lacquer. It looked fine, but required a lot of sanding to get it level as it just doesn't flow well. If you add enough retarder to get it to flow, then it's susceptible to dust, just like varnish. It seemed to cure, eventually, but didn't wear as well as sprayed lacquer or varnish.

Pat

_________________
formerly known around here as burbank
_________________

http://www.patfosterguitars.com

If you are going to use a brush there are other finishes that are easier to apply, and much, much less toxic than lacquer. Oil varnish for example.

_________________
Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

To me, the Minwax brushing lacquer smells a lot like the old Sherwin Williams nitrocellulose lacquer. I thin it and spray it, and its seems to work about the same as spray lacquer. When you brush it you are putting on what amounts to several sprayed coats, and it will take longer to dry and harden up. I would not add retarder to brushing lacquer. The Watco brushing lacquer doesn't seem to be as flexible a finish (less plasticizers?).
As other posters have mentioned, you can spray lacquer in near freezing conditions, just be carefull of rapid temperature/ humidity changes.

I have sprayed lacquer outside when it was 20 degrees in the northeast. The finish came out great. I would definitely continue doing this as opposed to using a brush.

_________________
Hutch

Get the heck off the couch and go build a guitar!!!!

Laurent, could you (or others) elaborate a bit on this? I've got a group of students who will be building with me soon, and I'm looking into other possibilities for their finishing work (something FASTER and EASIER than lacquer).

TIA,

_________________
Ken Mitchell
Durham, NC

Oil varnish will be the easiest finish to brush, although there is a learning curve. The slow cure guarantees that the finish will flow evenly if properly applied. The little dust particles sand right off. However, it is not fast. Most oil varnishes require 36 hours between coats, for an average 8 coats for a thin finish (.003" -.004"). Only Rockhard allows 2 coats/day, but it requires about 10 coats average.
The fastest finish I know is French polish, if polymerizing oils are added it will be a little harder. But it is no match for oil varnish or even lacquer in terms of hardness. The newly available U-Beaut shellac sounds promising though.

_________________
Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

Thanks for the info, Laurent. I think I will just keep using water-based lacquer.

_________________
Ken Mitchell
Durham, NC