Applying a Logo and a Finish
Another entry in the guitar build has arrived...
Applying nitrocellulose lacquer is a test of patience. It's a slow process to do right - but in it's defense, it's got to be just about the easiest spray finish to learn with.
Nitrocellulose lacquer for the most part has been replaced with more modern finishes including enamels, polyurethanes, water-based finishes, and of course - acrylic lacquers.
It is still a favorite among guitarmakers however, for several reasons, including that it's relatively easy to apply, it moves well enough to expand and contract with wood, and it buffs to a very high gloss. It's in the buffing that it really shines (pun intended), but that's a subject for a future post.
The logos are actually a water-slide decal, applied over at least a coat of lacquer and then several coats applied over them. The decal is basically the same some of you might remember from the old days of model-making, with a twist - with the advent of computers and printers you can now make pretty much any logo you want. Using a special paper designated (manufactured for either an inkjet or laserjet printer), I printed up a few ideas on regular paper to see how they would look.
Once I decided on logos, I printed them out on the special paper, then sprayed a coat of lacquer over top of the print to lock the print in place. Failure to do so will result in the print simply washing away when it comes time to soak the decal in the water to release it....
After soaking the decal in a pot of water for about 45 seconds, I slid the decal off the paper into place and flattened it with a soldering brush. It's very thin, very flimsy, and very difficult to fix if you mess it up - but if you get it right, it goes easy.
Once in place, I let the logo dry for a day then sprayed a few coats of lacquer directly over it, effectively burying the decal in the lacquer. Using a block and some 600 wet-or-dry sandpaper, I sanded over the logo to level the edges.... Though the decal is very thin, if you don't flatten the edges it is quite obvious. You just have to be careful not to sand through all of the lacquer and start erasing your logo, because the only cure then is to start all over.
Once flat, another coat of lacquer is applied and the necks are ready for a color (if so desired) and/or finish coats. The color coat, if needed, is usually to darken the wood to give the neck an aged look - most new Fender necks are not colored at all.
For the solid color bodies, I started off by applying a shellac primer - Zinser Bullseye primer (not the spray stuff - that stuff doesn't dry properly in my experience) in quart form. It give a good base for the finishes to follow, filling some of the imperfections of the wood.
Once satisfied with the primer, I went on to spray a few coats of lacquer onto the bodies, then waited for a few days for the paint to dry. Once dry, I wet sanded the bodies down to smooth out the finish, then applied a few more coats of lacquer.
I repeated the process 3 or 4 times, until I had a good base built up. For the black guitar I was done - it has enough paint on it now that I should be able to buff it out without going through the color. The black was a mix of clear Behlen instrument lacquer and Transtint black dye.
One thing I can tell you is that it is just about impossible to photograph this black thing in my shop and have the image come out at all...
The Butterscotch Tele took a little more experimenting. I originally wanted to be able to see the grain of the wood through the finish, like you see on so many Fenders, but there was three things working against me. First, the wood I used was alder, and not ash - so the grain was not very pronounced. Second, the contoured arm cut kind of messed up the wood grain a bit so it looked a little off... Finally third was my inexperience. I just couldn't quite get the color I wanted - my first try looked too white to me, and the next coat I put on made it far too yellow.
The final color mix utilized Transtint honey amber, Transtint Brown Mahogany, Transtint Mission Brown, and Mixol white pigment mixed into clear gloss Behlen's instrument lacquer.
By the time I had the color I wanted, the grain was pretty much buried. No big loss, really, it wasn't that pretty - and lessons learned for the next time will make my approach better then.
For the sunburst Tele, I started off by filling the grain - walnut is such an open pored wood that its much easier to fill with filler than finish....
I sprayed a few base coats of lacquer on the body then taped off the binding and sides for the sunburst. I did each face separately to reduce overspray.
Once taped off, using a detail gun - a Wood River HVLP air detail gun - I sprayed an outline of black around the perimeter of the body. The spray gun was the third in this journey (3 of 5). The first I had was an old siphon-feed detail gun from "the old days" 20 years ago or so. It simply wasn't controllable enough to work well. The next was a Harbor Freight HVLP detail gun - I've had fair luck with some HF items, but this wasn't one - for one, I found out the nice anodized finish it had on it was - well, paint. I know because the lacquer reducer actually dissolved it. I was cleaning it thoroughly because the rubber washer that regulates the airflow to the tip had dissolved in the lacquer thinner.
I'm not too happy with the Wood River gun either - it's spray pattern is not up to snuff, and it doesn't lay enough paint down - but it was good enough to do the sunburst. I just sprayed around the perimeter of the body, pointing the gun away from the center of the body.
Once the black dried, I mixed up a batch of lacquer with the Mission and Mahogany Brown, and repeated the above process aiming just a little more toward the center of the body.
There was a bit of overspray in the center, but nothing a little sanding wouldn't cure. Before I did, I removed the tape from the binding and fashioned a small scraper from a short chunk of dowel, a small nut and bolt, and an Exacto blade and went to work cleaning up the edge of the binding.
I then did the whole process to the back of the body:
Once it was all cleaned up, I wet sanded the finish removing any overspray and as a result dialed back the sunburst just a bit, something which I expected.
Finally, it was time for several finish coats of lacquer - spraying three coats in a day, allowing it to dry for at least several days, wet sanding, and applying three more coats until all the little imperfections in the body were filled.
The bodies now sit drying for at least 3-4 weeks to harden up enough for buffing. Summer temperatures are gone, so the finish needs the longer time to properly set up. The necks all got finishes during this period as well, I mixed a bit of amber into the clear to give them a just slightly aged look. They now wait to dry as well.
The next entries will have me installing nuts on the necks and cobbling together a buffing arbor from the bones of an old homemade drum sander I built several years back and (of course) buffing out the finishes.
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