Tuesday, December 29, 2009

Gluing on the top

Got back from visiting relatives today. Finished setting up the top of the rim where I wanted tonight, so I glued the top to the rim.

I spent a lot of time getting the top so that it fit nicely to the sides, without much pressure necessary to hold it in place. Still, I used a few clamps in critical areas just to make sure everything is tight.

I used a bicycle inner tube. It's a single inner tube, that I cut with a scissors in a long spiral, to make it about four times as long as it started out.

Wednesday, December 23, 2009

More bracing

Our digital camera is back. We sent it in to have it repaired by Canon, just in time for Christmas.

A week or so ago I took a little time off from the guitar. I've been really motivated to work on it, but there were a few days when I made a couple of minor flubs and it was feeling to me like my head wasn't in the right place to do exacting work. So I gave it some time off, and came back to it this past weekend.

Since then, I've been working on the top and the back. I work on the guitar each night after my son goes to bed. I've developed a nice routine, and lately I really look forward to working on it every night.

I've slotted the rim to accept the top and back bracing. I've also been re-studying the bracing of early 30's Martins, and have been shaping the braces to look as much like what I see in pictures, as I can get them.

I'm realizing that I missed a lot of details on the bracing of my first guitar. I thought I was copying old Martin bracing, but there's more to it than I had thought. There's the height of the "peaks," and the depth of middle of the scallops, and the slope and shape of the scallops themselves. Each peak has material taken of the sides of it. It's the height that gives the brace it's stiffness, but the width of the brace allows more vibration. I hadn't quite grasped that, yet am still working on it.

I've also calculated where the bridge will be placed on the top and have made the bridge plate so that it will fit right around it. It won't be any larger than it needs to be.

To work on the braces I went out and finally bought a really nice chisel. I didn't realize just what an essential tool this is! I was just fumbling, before.

I've been doing my best to tap tune the top. My ear has more to learn in that regard, but I'm finding that I've developed in that area also. While shaping the braces I can hear the top becoming more responsive, as well as developing sustain. This guitar is going to have some stuff going for it that my last guitar didn't!

In each pic below you'll see my braces first, then a picture of a 30's Martin guitar. I still have a little more cleaning up to do on my braces, but I'm almost there.

Thursday, December 17, 2009

Still working on the rim

I've been taking my time trying to get the rim just right. I'm using 2"x2" with radii (radius plural?) cut into them, and sand paper applied to the radii. I spin these sticks around and sand the rim, so that the radii are transferred to it, which will match the radii of the top and back.

The work has been pretty slow going, as I don't want to take too much off of one side. I think I've pretty much got it pretty close, except for the "shoulders" on the back. I have more to take off there, and then I'll need to notch the kerfed lining in order to insert the bracing.

I didn't anticipate using the cradle, that I built to go with my binding jig to sand the rim, this way. But the mold fits right on top of it, and with the height adjustment, I'm able to make it level. I mounted that little 1/2" metal pole in the middle of it, and it worked out really well.

I may use this same set-up to glue the top and the back to the rim, also. We'll see.

Tuning Machines

On my first guitar I messed up the placement of the tuning machine holes on the peghead. This time I made a template. It's a scrap piece of mahogany. Here it is sitting on top of the peghead.

I think it's going to be a good idea to drill the holes before doing the finish. If I finished the peghead and then drilled the holes, I'd likely scratch or dent the finish, as I need to clamp it in place to drill the holes.

I marked holes on the peghead veneer using a white colored pencil.

The last time I did this, I used a neighbor's drill press. As a result, I think I hurried the job. This time I'm using my own newly-acquired press. It's small, and used, and fairly old, but in good shape. It does a good job.

First I drilled 1/4" holes for all six tuner posts. Then I drilled 11/32" holes, only part way into the top, to only accommodate the bushings. This makes for a nice snug fit. Stew-mac makes a bit that centers this hole, but I just wiggled the peghead until I got the larger hole centered. I think I got it done really well this way.

Here's what it looks like, all done. After drilling both holes, I insert the 1/4" bit again, thru those bushings, to insure that the tuner posts won't be rubbing against anything.

I had a little tear out on the back but it will be covered up by the tuners.

So here's what the back will look like.

These are the Grover Sta-Tites with "vintage style scalloped knobs." The gear ratio is 18:1.

Monday, December 7, 2009

Pickguard and naptha

I ordered a Greven Tortis 30's pickguard from myfavoriteguitars.com, which arrived in the mail today. Here it is sitting on the top to give an idea of how it will look.

Hmmm, as long as we're considering how it will look, how's about I wet the top with naptha to approximate the appearance of the wood after being finished?

I wish our camera wasn't broke so you could really see the nice striped figure in that top...

And here also is the "end graft," wetted with naptha.

And as long as we're considering how it will look, here's some of the other parts just placed together to give you an idea.

The bridge is a Martin rosewood bridge with a long vintage saddle. John Hall cut the belly part of it off, and I rounded the edge of it to make it match the front. I couldn't find where to buy an old thin saddle like that, but doing it that way really does make it just like the old ones...

Sunday, December 6, 2009


I've done fretwork before. But I've always hammered the frets in, checked them for levelness, then leveled with a 14" file, and then recrowned them.

This time around I've got a different idea in mind. This time, what I plan to do with high problem frets, is take them out and replace them. I want to get the frets seated evenly so that they're really close to each other in height, as close as I can get them, before I begin filing and recrowning.

Here's a better detail of the dot inlays.

Completing the Rim

I didn't realize just how bad the webcam pics were until I looked at them again after they had been uploaded. For these pics I'm switching to our phone.

I glued the neck block to the rim last night. On my first guitar, I used a Martin neck block. It was simple to set up. I just made the top of the neck block flush with the top of the rim. I like this neck block better. It's older in style. But it required a little more know-how. I placed it so that when the neck tenon is placed into it, the fingerboard will be 3/16" above the top. This will give some room for later on. When I fit the dovetail, the neck tenon will sink down into the neck block mortise, until the fingerboard is flush with the top.

After the block was clamped in place, I got started on kerfed lining. I use clothespins reinforced with rubberbands as clamps.

Here's the completed rim job. I used a battery powered drill and a chisel to make that v-slot around the neck block mortise.

And here's the neck's dovetail tenon resting in the body's mortise slot.

Now I just need to fit the top and back to the sides. I'll sand the rim using 2x2's that have the radii of the top and back cut into them. Then I need to shape the bracing so that it is all shorter than the binding at the ends, so that the binding will cover it all up. After that, I'll cut notches in the rim to accept the ends of the bracing. I really believe that taking the time to get a nice and tight, yet stress-free fit of all these parts really helps out the sound quite a bit. It's the kind of thing that doesn't happen on most factory-made guitars.