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OK, I finally carved out some time for the kit. I am assembling the rim, and I do have a mold. When I place the rim in the mold and press the sides out, there is overlap on the ends. Am I correct to assume I am to cut (trim) these parts to fit? (based on good conformance to the mold)...

Second, the upper bout block is slightly (1/8") taller than the rim. Should this be trimmed before glueing? Same for lower bout end block. In both cases, the block is extending above the back of the rim.

(ps: I saw a good example of expanding the bouts in the project #2 guitar forum which I plan to use).

Mike

The block are to be trimmed now and as for the side set , you want to trim the set so that as you close the mold the waist wants to come up off the mold. Then when you use spreaders to push that back the set will be forced to the mold for a tite fit
jhon hall BCG

Not sure what you mean by "the waist wants to come up off the mold"...

Ok, John, I went back to the shop and looked at the setup again. With nothing trimmed, the sides are in the mold, the lower bout of the mold is open, and I butted the ends if the sides together. When I (gently) attempt to close the mold (there is over one inch in the gap of the mold at the clamp) I can see the waist of the sides move away from the mold waist, but I still have over 3/4" of an inch to go to close the mold.

I am not forcing the gap closed...just trying to see what you are referring to. So, at this point, do I trim a bit off the end of each side (lower bout) and then attempt to close the mold again, and as soon as I see just a little movement at the waist (away from the mold) as the mold closes, then I have it right? At this point, the mold is closed, then apply the spreaders and glue the blocks?

Mike

Mike,

This is what I did. Get a flat clean piece of stock to sit the mold on. Put a line on the clean flat stock (that's your center line). Close the mold and place it on the the flat piece with the mold centered on the line (hold in place with blocks screwed down into the flat piece and against the mold). Place one half of the side in the mold and clamp it to the mold (make sure you have the same amount over the center line upper and lower bout) mark the center line with a square. When you cut leave the line. Do the same to the other side and clamp both sides to the tail and head block out of the mold. When dry install back in the mold and install your spreaders.

That's what I did and see what others have to say.

Peter

Oh yeah I would leave at least an good 1/8" of the blocks sticking up so when you put the radius on you have some stock for the radius of the top and back.

When dry? My sides are already bent if that is what you are refering to.

But I do see the point about securing the mold to flat stock...

Mike

OK, I am starting to understand. But I am unclear on leaving block stock above the rim (in the back). Let me phrase it this way. Does any block stock (upper and lower bout blocks) extend on both sides (top and bottom)? or just the bottom? 1/8"?

Even so, at this point, I still do not understand why.

Mike

    There is a radius on the back and this will actually plot to a dynamic ( varying angle ) as you go around the guitar. If you place a back brace on the back as it were in the guitar , you can visualize the angle of the kerfing at that point.
   A 4-5 degree angle works for the first few so that you don't have a flat spot on the kerfing. You want the joint on the back to be as flush as possible once you get to that point.
    The blocks will also get this effect and this is what pls53 is refering to I belived. Once you glue in the kerfing you want to keep this in mind and not just sand them flat.
john hall
blues creek guitars

OK. So the top of the guitar, the blocks and kerfing are flush to the rim and the surface of the kerfing is at a 90 degree angle to the rim.

On the back of the guitar, I leave about 1/8" of each block above the rim. The kerfing is attached in a similar fashion (1/8" or so) above the rim. When all is dry, then I sand the blocks an kerfing so that the blocks and kerfing rise at a 4-6 degree angle above the rim (towards the center of the guitar). This will then allow the back to be attached with an arch.

Have I got it right now?

Mike

Mike:

http://guitarmaking.blogspot.com/

Check out the site above. It's a site from one of our members, Jon Kendall. It's FULL of great information. Go through the old months...the early months in Jon's building. Those are FULL of stuff that'll open your eyes. Pictures are worth thousands of words.

Hope that helps.

Bill

_________________
Eagles may soar, but weasels don't get sucked into jet engines.

Thanks Bill... Thats what I needed.

Mike

OK, getting ready to cut & glue. Somebody please say "yeah" to this: leave the top bout block and the bottom bout block 1/8" taller than the rim (rising out of the back of the guitar)

Mike

The sides are profiled, but I think I am lost on the radius stuff. Guess I need to go to school

Mike