Mohawk lacquer

[David Houchens]

Do any of you builders use Mohawk lacquer?
Have you bought any recently?
I've been using Mohawk stains in my shop for years. A month or so ago I thought I'd try their lacquer as well.
I've been spraying different lacquers for quite some time, so not a new thing.
I spray 3 times in a day about 45 - 60 minutes apart. The humidity in my shop stays in the 40's. I generally skip a day so it cures well between layers.
I'm spraying a small guitar.
After 4 days of spraying I notice check cracks appearing on the top.
Well maybe its a bit too heavy. So I sand it back and start again making sure not to spray heavy and sand plenty between coats.
Weeks later I'm fitting the neck and notice a check crack in the top. next day there are many check cracks.
Any suggestions welcome. Thanks

[David Houchens]

Can't seem to load a pictures a picture I select the file and it shows in the window but never given an option to upload.

[rcc56]

I rarely shoot lacquer from a gun, and when I do, my cabinet maker friend with 30+ years of experience usually handles the mixture and the gun.
That said, the last couple of jobs I did were with Mohawk, and there were no problems.

I will mention that the late Jim Grainger, who ran a repair shop for 40 years, preferred Mohawk lacquer. He said that a big part of his reason for that was Mohawk's excellent customer service. When he had a problem, he called them, and they sent someone over who spent a significant amount of time with him, going over application, mixture, etc. etc. They wanted him to be a satisfied customer, and were willing to go out of their way to work with him.

I don't know if Mohawk still operates in that manner, but it would be worthwhile to give them a call to find out. With a little luck, they may even be able to help you solve your problems over the phone.

[sunburst]

I recently let myself run out of Mohawk lacquer in the midst of spraying several projects and had to order (and wait for) a couple of new gallons. No problems with any of the items and they are all still here in the shop.
I don't know if there is a batch number on the can or label, but I'll check mine and report back if I find anything.

FWIW, the only times I've had checking problems with newly (relatively) sprayed lacquer was when the lacquer was old and had been stored for a while and that is the reason I don't order more than 2 gallons at a time. Since yours is no more than a month or so old that shouldn't be the problem, and it might be a bad batch. Unfortunately, we know how difficult that can be to deal with...

[Dale Ludewig]

I've sprayed Mohawk products for many years, including their instrument lacquer, piano lacquer, and vinyl sealer. I've never had a problem due to their products. I did have checking problems once and that was my fault. I sprayed piano lacquer on a mandolin or a guitar (forget which) and that did what your photo shows. Evidently the instrument lacquer has more plasticizers in it than the piano lacquer which makes it more flexible in dealing with expansion/contraction issues on thin wood that moves a lot from humidity changes. But that took awhile to show up, like several months. I'd call them. My contact with them has always been good.

[sunburst]

I looked the can over thoroughly and did not find an obvious batch number. Perhaps there is a code somewhere, but I guess that info would have to come from Mohawk.

[Marty Jacobson]

I had this happen with Mohawk lacquer several years ago (2014). My air supply was not perfectly dry. I solved the air moisture problem with a drain cup thing and line dryer. No problems after that, I shot several gallons on instruments and furniture without anything similar happening again.

Umm... charge extra and say it's pre-aged, the "loosened up" lacquer will make it sound better? /s

[David Houchens]

Thanks to all. I do get a moisture in my air lines but have traps and try to stay on top of it.
I'm glad to hear the lacquer is more than likely ok.
Onward thru the fog.

[Lynn Dudenbostel]

Which Mohawk lacquer are you using?

[David Houchens]

It's the M610 10-25807 clear lacquer. Possibly the wrong kind.

[David Houchens]

Just typed the number on the Mohawk site. Furniture finish. I assumed my sales rep would know Bryce Instruments would want lacquer for instruments. My bad. Homework 1st, place order 2nd.

[sunburst]

Bummer for you, but a bit of a relief for me knowing it wasn't the instrument lacquer! Guess you'll have to strip it down and start over...bummer (again).

[David Houchens]

Yep. Nothing quite like backing up. Oh well, hopefully a lesson we'll learned.

[thistle3585]

I've had this happen several times with several different cans of lacquer from Mohawk. I had contributed it to the shellac that I used as a sealer not properly drying. I think my shellac was past its date. I haven't had the issue once I started using their sanding sealer.

[David Houchens]

I mix my shellac from flakes but that's a thought. I just ordered their instrument lacquer. I'm hoping that will solve it. I had ordered the wrong product. This old brain ain't what it used to be.
I think there's only to brain cells left and they don't talk to each other.

[David Houchens]

That is very hard lacquer. It was a royal pain to remove. Scraped a good bit of it. I steamed out the neck and removed the bridge. Have the body at 80 grit. Hope to re-stain today. I understand why it check cracked. Lesson learned

[John Arnold]

I have used both the Mohawk classic instrument lacquer and their piano lacquer. The latter has a higher solids content but less plasticizer. That makes it more susceptible to cold checking. I do like to minimize the thickness, and that helps with checking. Another bonus with piano lacquer is that it hardens up much quicker. With any traditional lacquer, ventilation is key to hasten the hardening process, since the curing is strictly via solvent evaporation. In this regard, a box fan on the lowest speed helps significantly.
One thing I learned recently is that the plasicizer settles out in the can, so you need to stir it up before using.