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Spray can lacquer with the least-to-none alkyd poly?
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Author:  KawaiianPunch [ Sat Feb 25, 2017 1:03 pm ]
Post subject:  Spray can lacquer with the least-to-none alkyd poly?

I need some recommendations. I want the most rock-hard finish that naturally cracks and yellows; in rattle-cans. I don't mind it being brittle. I've only known Deft.

Thanks.

Author:  Michael.N. [ Sat Feb 25, 2017 1:48 pm ]
Post subject:  Re: Spray can lacquer with the least-to-none alkyd poly?

You need to put something soft as a thick base coat, then something hard and brittle on top of it. Guaranteed to crack, given time.

Author:  KawaiianPunch [ Sat Feb 25, 2017 2:08 pm ]
Post subject:  Re: Spray can lacquer with the least-to-none alkyd poly?

Michael.N. wrote:
You need to put something soft as a thick base coat, then something hard and brittle on top of it. Guaranteed to crack, given time.


Something like Fullerplast?

Author:  Joe Beaver [ Sat Feb 25, 2017 4:46 pm ]
Post subject:  Re: Spray can lacquer with the least-to-none alkyd poly?

Not sure what you are trying to do. Are we talking clear coats? On wood? Trying to match the look of a vintage instrument?

Author:  KawaiianPunch [ Sat Feb 25, 2017 6:25 pm ]
Post subject:  Re: Spray can lacquer with the least-to-none alkyd poly?

Joe Beaver wrote:
No sure what you are trying to do. Are we talking clear coats? On wood? Trying to match the look of a vintage instrument?


Clear coats for now.

Those are the attributes I like and I'd like recommendations that would best achieve those results.

I've owned a few pre-CBS Fenders and a 1920s Martin. I'm not trying to copy any look.

Author:  Woodie G [ Sun Feb 26, 2017 8:01 am ]
Post subject:  Re: Spray can lacquer with the least-to-none alkyd poly?

Instrument lacquers have a specific formulation that trades off some surface hardness and faster drying time in favor of greater flexibility to accommodate wood movement and the cross-grain and mixed materials construction practices common to many musical instruments. Spray can packaged lacquers will have a similar formulation to allow successful application with a 'spray bomb), and will share some of the slower drying/softer film attributes of the Mohawk, McFaddens/Seagrave, and Cardinal instrument lacquers delivered in cans. In other words, it will take years for rattle-can applied lacquer to show much in the way of checking, unless it is encouraged through the use of a less flexible undercoating, such as the polyester-based filler Fender used under lacquer, or with methods such as using canned air to locally cool the film to induce checking.

Similarly, today's nitrocellulose lacquers are water white formulations that show little yellowing or ambering over time. If applying canned lacquer with a spray system, dye can be added to the mix to approximate the yellowing or ambering seen with older lacquers, but you'll have to go to a prepared rattle-can mix from Stewart MacDonald, Gracey, or ReRanch that has an amber or yellow dye added.

Author:  Clay S. [ Sun Feb 26, 2017 8:23 am ]
Post subject:  Re: Spray can lacquer with the least-to-none alkyd poly?

One way to achieve cracking is to spray a thick finish and then temperature shock it. Stick it in the freezer and then place it in a hot closet. Many finishes have been accidently "reliqued" by going from a cold car trunk to a warm room. You could use several coats of a traditional straw colored nitro brushing lacquer if you don't have a spray gun.

Author:  B. Howard [ Sun Feb 26, 2017 8:30 am ]
Post subject:  Re: Spray can lacquer with the least-to-none alkyd poly?

KawaiianPunch wrote:
Michael.N. wrote:
You need to put something soft as a thick base coat, then something hard and brittle on top of it. Guaranteed to crack, given time.


Something like Fullerplast?


Fullerplast is not soft.... just a trade name for a polyester coating that is much the industry standard now.

You will not find what you are looking for in a rattle can. You will not even find it in a gallon these days. The thing is the way the base stock of nitro chips is made today. It has more plasticizer in it at that point even as a raw material than you are looking for. Some of the reason for this is to prevent it's conversion to high explosives in the modern world we live in and also because it is cheaper to make this way.....

Author:  KawaiianPunch [ Sun Feb 26, 2017 1:06 pm ]
Post subject:  Re: Spray can lacquer with the least-to-none alkyd poly?

Thanks for the replies.

I'm not trying to fake distressing. I want it to naturally exhibit these properties over the next 10+ years of playing.

I've been reading good things about Minwax and Watco and will experiment with those since I'm new to woodworking. The reviews say they dry hard and become brittle over time. Deft seems to be the worse in terms of drying and hardness.

Author:  Clay S. [ Sun Feb 26, 2017 9:07 pm ]
Post subject:  Re: Spray can lacquer with the least-to-none alkyd poly?

" I want it to naturally exhibit these properties over the next 10+ years of playing."

Often the cracks appear after a moment of inattention when someone opens a guitar case in a hot room that was moments before in a cold outdoor environment. The dirt that gets rubbed into the cracks that make them standout takes a little longer to accumulate.

Author:  truckjohn [ Mon Feb 27, 2017 2:03 pm ]
Post subject:  Re: Spray can lacquer with the least-to-none alkyd poly?

Seems like all you need to do is to use real rattle can instrument lacquer without any vinyl sealer coat underneath... Just spray straight on the wood. Just get some Stew Mac spray lacquer and go at it. Time will take care of the rest for you. ;)

Author:  KawaiianPunch [ Tue Feb 28, 2017 6:46 pm ]
Post subject:  Re: Spray can lacquer with the least-to-none alkyd poly?

I found some Watco and Minwax and walked out with Minwax lacquer in gloss. The number I found on the can was "lm-15200-0000B" but it doesn't show on the internet. I wonder if this good percentage of nitro.

The safety sheet MSDS doesn't say nitro, though. https://www.minwax.com/document/MSDS/en/027426152007

Edit: Some people on TDPRI contacted Minwax last year and confirmed it was still nitrocellulose: http://www.tdpri.com/threads/notice-min ... re.683714/

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