June 11th, 2012, 08:18 PM
I'm new to building guitars and this site has been an amazing help. I searched and have been reading related topics, but haven't found an answer for this. When wood becomes blotchy after dying it, can it be fixed or is the best solution to sand it off and start over? Could redying it without resanding it potentially work? This is probably basic, but I'm sure someone can help me. Thanks.
June 11th, 2012, 11:10 PM
It is very hard to stain soft maple and have it come out looking good, but it can be done. The density of soft maple varies and the softer areas soak up the stain more than the harder areas. I would sand it back down. If you can't get it all off, that would be OK. The stain that stays will highlight the grain. Then I would mix a little stain with a clear finish and spray thin coats until you get the color you're looking for. Tint the clear just a little. As you build up coats, the color will get deeper. Once you have the color you want, you can spray clear over it.
June 12th, 2012, 12:18 AM
^^^What he said. Sand as much off as you can, I wouldn't worry too much about not being able to get it all off. Sand down to 220 or 320, and a good smooth finish.
One way that works very well for me is illustrated in the O'Brien Guitars "Luthier Tips duJour" Videos, put on by LMI. They are all very good, and have never steered me wrong. Two videos here that may be of interest to you, one on sunburst finishes, and one on electric guitar finishes. I use the method he mentions for Sunburst finishes--using shellac for the color coat carrier, but it works fine for solid finishes, too.
Here's a link: http://www.youtube.com/watch?v=ru5jkNG7_zU&feature=player_embedded
Their technique is to "pop" the grain by wiping on black, or other color, then sanding back to reveal the grain. The color is simply tint mixed with denatured alcohol or lacquer thinner.
Then, as Nosmo mentions above, mix your color with a finish--O'Brien recommends a superblonde or Platina DEWAXED shellac in the sunburst video, which is what I use. . Best to get flakes, mix it with denatured alcohol so its fresh. If you don't have a compressed air spray rig, a Preval sprayer, recently available at Home Depots, works fine for this.
The shellac (alcohol) or lacquer thinner actually, flashes off very rapidly, so you can build color coats quickly. The first few will look not-so-hot, too light, etc., but give it a little time to dry between sparyings, and you'll build up coats. Be careful not to get any runs, but if you do, allow to dry thoroughly, and sand flat, and start spraying again.
One of the main reasons I like to use shellac for the process is that in my experience, it is much easier to sand off shellac, and clean it up with denatured alcohol, if you make a boo-boo, than lacquer and lacquer thinner. You can overspray the shellac with anything you like, once its dry.
For maximum flatness and good finish, every couple of color coats, give it a light sanding of 600 grit or so. CArefully wipe off the sanding dust, and spray more.
Then let it dry a bit until completely dry, and you can start building your clear coats.
June 12th, 2012, 05:35 PM
Thanks guys, the information and that link were great. I will have to work on getting some equipment to spray.