Grafted Coatings, Inc.: The Guitarmaking World’s Secret Finish

Grafted Coatings, Inc.: The Guitarmaking World’s Secret Finish

In what may be the clearest example of the tail wagging the dog, a family-owned manufacturer which set out to create coatings for the door and window market has recently become the darling of an elite segment of wood finishers: guitar makers. Grafted Coatings, Inc. did not set out to win that market, but a few luthiers discovered their premium finish and coaxed them to fine-tune it to fit their ideal. This finish luthiers love is a super-durable cross-linked coating with the rather inelegant name KTM-9.

“You can brush or spray KTM-9,” explains Tim Bolton, the vice president of operations. It is easy to apply, predictable, stable, and it flows out beautifully. It has good penetration and wetting, and the high solids help it build quickly with fewer coats. Perhaps most importantly, it doesn’t look like a typical waterbased coating. KTM-9 helps pop the grain better and doesn’t have the bluish haze and lack of clarity that you often see on other waterbased coatings, especially with thicker or high gloss finishes. In short, it has the advantages of waterbased finishes combined with the warmth and depth most people associate with lacquer.”

So far, the company has remained largely below the radar of other woodworkers and furniture makers, but I suspect that may change. How this family company even came to be involved with coatings at all is a story in itself, and one that is almost as unlikely as a finishing product that only guitarmakers seem to know about.


It started with Tim’s father, 74-year-old James A. Bolton Jr. “After graduating from Providence College with a degree in biology,” Tim recounted, “he sold insurance, was a road salesman for Coca-Cola, and was a pharmaceutical industry salesman who worked his way up the company. During the height of the first energy crunch in the 1970s, he left abruptly to sell insulation. He’d locate bad insulation jobs by inspecting for heat loss with an infrared scanner. His intent was to sell insulation, but it also had the effect of indicating poor workmanship, which inspired him to go out on his own.

“Noticing most losses around windows, he started making and selling indoor storm windows. This system of Plexiglas® sheets with magnetic strips that attached to your windows was quite popular during the 70s. You’d put them on a window, and they would stop 100 percent of the airflow leaks. By the early 80s, the interior storm windows became less fashionable, and vinyl replacement windows started becoming more popular, so we started into the remodeling business selling vinyl replacement doors and windows, then eventually making wood window systems as well.


“People want windows that look like wood but are maintenance-free,” Tim pointed out. “As a result, the vinyl manufacturers try to make their windows look like wood, and the wood people try to make theirs act like vinyl. What makes a wood window act like vinyl is the coating. When we started making wood window systems, we noticed that finishing was one of the most expensive parts of the process. A lot of that was due to the setup costs for solvent-based systems and dealing with the resultant VOC regulations. Waterbased seemed to be not only the better way to go, but a cheaper way to go as well. Not happy with the options out there, we started making our own coatings in 1992.

“Our early waterbased products required the user to add a separate cross-linker to convert the finish to an ultra-durable one. Gradually, over the past eight years as the technology improved, we started switching over to one-pack systems. They make the system easier to use for the finisher, more predictable in that you don’t have to wonder if an employee added the cross-linker in the right amount, and also much safer. Handling some of the old cross-linkers in concentrated form was somewhat dangerous. One-package self-curing systems like ours are much safer to handle, yet still have more than a year of shelf life, because the cross-linkers don’t kick in until the system starts to air dry.


“Initially, we formed a separate company to sell waterbased coatings to the millwork industry, but a few years ago, one of our sales reps introduced our product to the guitar making industry, and before we knew it, we had a niche market. We made some changes that made it more appropriate for luthiers and came up with a coating that is harder, has higher solids and better clarity, an amber tint to make it look more like solvent-based lacquers, and the ability to build multiple coats in a day, all in a brushable material. Of course, you can also spray it.

“Our main products are still for the door and window market, including one rather unique patented coating we make, a wood graining finish kit for embossed fiberglass or steel doors. It works on both raw and painted wood, too, as long it is a wood with open grain. Other clear finishes include a spar varnish called KTM-SV which, like KTM-9, can be used indoors, outdoors and is even tough enough to use as a wood floor finish.” If there is one catch, it is that finishes like this are not cheap. The KTM-9 goes for $85 per gallon, and the SV for $61 per gallon.


When it comes to the company itself, it is very much a family affair in several ways. “Half the employees are family members,” Tim told me. “Even the name of our finish line comes from the first letters of 12 of Jim’s grandchildren, who coincidentally all had names starting with K, T, or M. “Tim is quick to point out, though, that their definition of family extends far beyond mere blood lines. “My father envisioned this as a family company. We’re a big family, and a growing one, because we treat our employees like family, too. Our goal is to make safe products in a safe work environment and sell things we are proud of to loyal customers.


“It’s not enough to just make a can of paint,” he insists. “It has to actually produce a finished product once it gets on the surface. When you look at any wood product, the first thing you see is the finish. Putting our finishes on wood transforms it into something that is beautiful and durable, and adds years of life. As our slogan says, ‘It’s not just paint. It’s a KTM finish,’ and that is really how we feel.”

Posted in: