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I'm repairing a cracked side of a Martin J12-16GT, small indentation and small crack, and I'm thinking of how to best blend the satin finish. I was thinking of using drop fill lacquer, but I am not sure of what method to use to get the satin finish to blend? Any suggestions? Clinton

I was told about a product from Mohawk called "Perfect Blend" which is designed expressly to match touch ups with existing satin or matte finishes. They make a range of sheens.
From what I remember you use regular gloss lacquer for the touch up and once it's done and the surface complete, the "Perfect Blend" product (not more lacquer but just the flatting agent) is applied to match everything.
If you get some and use it, post a report please.
Also you didn't tell us what the Martin finish is, if it's their cross-linked finish you should check the compatibilty of the materials.
The Exeter NH repair guru Pat DiBurro mentioned this at ASIA so perhaps he could give you more info.

Are you sure it's a lacquer finish and not a conversion varnish? Lacquer will not adhere well to a conversion varnish.

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Brian

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

https://www.howardguitarsdelaware.com/

Brian, from what I'm digging up on the internet, I thought it was lacquer?
David, thanks for passing on that information about the "Perfect Blend", but now I'm doubting whether it's lacquer. The damage is on the side half way between the waist and the lower bout, on the players side . I wanted to, at least , address the crack and indentation so it doesn't get worst but I may pass on the finish if I can't confirm what the finish is. From the responses, even if it was lacquer, using a drop lacquer fill and dulling the finish, isn't the best approach. Thanks for your replies, Clinton

martin does not use varnish

_________________
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 just steel wool it after the drop fill is complete, then steel wool the general area (with various grits to match the sheen) to make the drop fill less obvious. Matching sheens aren't the problem, it's the fact that Martin stains their mahogany sides, making an invisible touch up impossible if you have raw wood exposed.

Most satin guitars already have uneven sheen, the moment anyone touches them the finish gets a slight polish.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

I just finished up a repair on a Martin that had a hole punched in the side. It had a satin finish.

I actually used Watco Satin brushing laquer thinned 50/50 and sprayed on with an airbrush .

There was of course overspray at the border of the repair, but I then took some Behlen's Blush Eraser, and blended the finishes together with that. Worked perfectly!

You have to be careful with the blush eraser and spray LIGHTLY so as not to get any runs, sometimes I erase twice.

I wish now I had taken a picture, but I wasn't thinking about that at the time as I do this quite routinely and it didn't occur to me to do so. I think the Martin finish must have been laquer as the result was seamless.

You can actually drop fill the crack, sand it smooth with a block, spray several coats over the region, and then erase.

Some people use superglue for the drop fill to speed up the repair time, and spray laquer over that. I've done that once or twice with good results, but I feel funny doing it so I just use laquer.

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Old growth, shmold growth!

I drop filled with CA on a Kamaka ukelele, and for some reason the CA reacted with the finish to produce something that shrunk at a greater rate than the lacquer itself. It was not seamless. I guess it depends on the brand of lacquer used but be very careful with CA reacting with the finish. The finish was permanently changed, and all I could do was strip it and redo the area.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Even on the non usa models? Thought the satin Mexicans were a conversion varnish or some other poly.

_________________
Brian

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

https://www.howardguitarsdelaware.com/

Brian, that's what I thought also, however, I could of had bad info. Great idea on the Blush Eraser. Too bad I can't do a test. I'm sending my client a disclaimer on the finishing part of the repair and let him make the decision. Clinton