Mark (TheCraftsmansPath.com) on May 22nd, 2008

With the bracing completed and the notches cut into the kerfed linings, it was time to start the work to attach the top to the sides. However, this task was not going to be able to be completed without some creative clamping.

Because the top must be clamped all along its perimeter, any normal clamping scheme would require quite a number of clamps in oder to adequately attach the top to the sides. When I previously glued the braces to both the top and back plates, I used the go-bar deck with flexible go-bars as clamps. This technique would also work for attaching the top (and the back as well) however, there are a few issues with it. First, in order to do it I would have to cut down all of the go-bars due to the hight of the sides. Second, because there is a radius along the edges of the sides, the setup would not be very stable to clamp with go-bars without something to compensate for that radius.

Spool_Clamps.JPGSo, what to do? Go out and buy a bunch of light duty clamps? No – just borrow another page for the old-time luthery book and make some spool clamps. In the picture you can see the pile of these that I made. Twenty-four of them, to be exact.

The spool clamps are fairly simple to make – an 8″ carriage bolt, some 1 1/4″ dowel rod, some fender washers, wing nuts and cork. It was a bit tedious to glue the cork to the pieces of dowel – I did this in strips (after the dowel pieces were already cut) and then trimmed the cork to the edge of the dowel with scissors. Not pretty because the cork is a bit crumbly, but it works. The only other issue was drilling holes through the dowel and cork for the carriage bolts to pass through. To do this I cut a circle in piece of MDF and cut a line with the band saw into circle from the edge. This allowed me to squeeze the circle closed with a screw in order to clamp each piece of dowel while drilling the holes.

Neck_Block.JPGScoring_Neck_Mortise.JPGTrimmed_Neck_Mortise.JPGOK so, with that activity all done, before I could attach the top, I needed to cut away the side material that was overlapping the mortise in the neck block. To do this I scored inside the lines of the neck mortise with a sharp utility knife and snapped away the side material. Finally I trimmed away the rough edges of the sides with a sharp chisel until they were even with the sides of the neck mortise. The rounded bottom does not need to be perfectly true because the neck tenon does not actually contact it when assembled.

Dry_Fit.JPGClamped_Top.JPGWith the neck mortise clear, it was time to dry fit the top, make any final adjustments and then glue it up. The important things here were to be sure the the neck edge was 3 15/16″ from the sound hole and that the tail edge was 20″ from the neck edge. I had previously measured these locations and marked them on the underside of the top with a pencil so, I was ready.

I applied glue sparingly to the kerfed lining strip along the top edge of the sides – I did not want any squeeze out on the inside of the guitar body. The clamping started at the neck end with a couple of Quick-grip clamps and a caul. With these clamps in place, I added a few spool clamps along the upper bout on each side of the neck block. This allowed me to then apply a clamp from neck to tail to bring the tail in to the 20″ mark. From there I just clamped the tail and added spool clamps along the sides – the last two being applied after the waist clamp was removed.

4 Responses to “Dreadnaught Guitar: Attaching the top”

  1. Mark,

    Pretty ingenious solution to a complicated glue-up, without having to buy a *whole bunch* of clamps!

    You have made terrific progress, and the guitar is looking like a nice musical instrument. I have enjoyed this journey with you – THANKS!!!

    Al

  2. Al,

    Thanks. I can’t take credit for the spool clamps – they are an old luthier tool/technique.

    I’m learning that there are lot’s of those old time techniques and tools that are very helpful on this project.

    Thanks for stopping by!

    –Mark

Trackbacks/Pingbacks

  1. The Craftsman’s Path » Dreadnought Guitar: Enclosing the body
  2. Cello clamps « Finely Strung

Leave a Reply