Bracewood - Part 1

A while back I began working with the three billets of bracewood that came with my kit. One was fairly straight grained and square with the grain, one was fairly straight but off axis, and the third was NOT straight at all. The first two I split to find the grain and then ripped along the grain. Then I split perpendicular to the grain along the medular grain. Unfortunately, this didn't yield anything very long because the medular was at a significant angle with respect to the length of the board.
See the third one at the bottom and the best I could do with the first two above that. So I called LMI and they sent me two more billets... they look straight at this point. I've been letting them acclimate to my basement over the past few days. Hopefully I can begin working with them soon.

Rationale: Braces are glued to the top with the grain top-to-bottom. It is important for the grain to be straight due to expansion/contraction of the wood during humidity changes. But it is actually more important that the medular grain is straight because this is the plane that is glued to the top. If any end grain is exposed at the gluing surface it significantly weakens the brace at that point. If end grain is exposed on the side of the brace along the normal grain it doesn't weaken the brace nearly as much as along the bottom of the brace in the direction of the medular grain. This is why bracewood must be split along the medular grain, while it is often acceptable to simply rip the billet along the grain direction if it is not too wavy.

Go-bar deck

I profiled the back to test my go-bar deck. I'll probably brace it first.

Daddy's little helper

My son loves to help dad... especially in the workshop with tools. Here is a good picture of us ripping some brace wood with the table saw.


He mostly just watches, but occasionally I find something that makes him feel "helpful".

Side struts

Last night I took the piece of mahogany that I cut off the end block, and cut it into 6 pieces to use as side struts. I shaped them on the sander and glued them on.
The struts are probably bigger than necessary, but that is ok.

Bridge plate placement

Funny thing. A friend of mine thought my bridge plate looked too low. This prompted me to remember that my plan is a 25.400" scale, whereas my fretboard is a 25.500" so I'll have to compensate a little. But all my measurements suggested the bridge plate was exactly where I wanted it. Turns out I had the original plan tucked away and was using a copy. The copy was real close, but slightly bigger than the original. The original was right on 25.400" (measuring from nut to 12th gives half scale), the copy is extremely close to 25.5 ! Sometimes you get lucky by accident.

Bracing pattern sketched

Last night I began sketching the bracing pattern on the bottom of the soundboard. First I put a cutout of the plan on the board and marked where the braces ended.


Next, I removed the plan and began connecting the lines. I made 5 deviations from the plan:
1) I didn't like the 2" gap at the sides between the top of the X and the UTB, so I made the top of the X meet the sides at the UTB. I left the lower edge of the X at the same spot. This effectively made the X slightly taller, forward shifting the center of the X just a bit.
2) I made the bridge plate slightly shorter by about 1/8". Final height is 1-7/8".
3) I reversed the direction of the lower tone bars, they now connect to the sides on the treble side and the X on the bass side instead of vice versa. The angle they make is 32º with respect to the bottom of the bridge plate.
4) I angled the finger braces slightly more, instead of perpendicular with the X. They are now at 62º with respect to the bottom of the bridge plate.
5) The width of all braces are slightly different, in most cases thinner than the plan. I'll try to add specific dimensions once I get them cut.

Oh, and I noticed that the whole is not centered, off by about 1/16". Thank you very much LMI. Not that it will matter or be noticed by anyone but me (and you:)

Kerfing sanded

On Friday night, I sanded both the top and back kerfing using the 30' and 15' dishes respectively. There were a few spots I had to get out the plane to even it out a bit... but for the most part it went quickly. I'll probably hit it again just before I glue the top/back to it.