Using a radius dish to sand kerfed linings...

[Logan]

Long-time lurker...all that.

I've been working on a StewMac kit for a bit now, but have been trying to do things as they would be done without a kit along the way, as my goal is to build my next guitar mostly from scratch. My bracings are all glued, kerfed linings are installed, and today I got ready to start sanding the top in preparation for closing the box. To do this, I am using a radius dish to do the top sanding.

What I notice (after I've already sanded quite a bit - stupidly), is that I am going to end up radiusing the entire top in order to get to the kerfings at the waist at all, since the Stewmac sides are completely flat on the top side. Is this right? I assume if this ok, I should have radiused the top before installing the linings to make this less work if nothing else?

[tippie53]

http://www.youtube.com/watch?v=QYHPCeVRUA4 this may help. You need to establish the neck angle to the top. This video will show you how .

[Logan]

So with the kerfing already installed, I sanded on the radius disc so that the kerfings are level about half to three-quarters up the lower/upper bouts. So would I just use an arched sanding stick to level the kerfing at the waist?

And in the video, when you put all your sanding weight at the neck, are you using the flat part of the disc I presume (not 100% clear to me)?

[Kevin Sjostrand]

Hi Logan,
You are correct that you should make sure your rims, top and bottom, are the right dimension before installing the kerfing which should be glued in about 1/32" proud of the edge. When you radius sand, you want to just sand the kerfing back down to the rim edge.
I'm not sure what you have been doing, but the rims for the top should be flat, an equal plain; as if you put a level across all axis and the bubble is in the middle of the level. For the top, you are only radiusing the edge.
I don't use a radius dish to do this, but it should work fine if you keep the dish over the center of your rims. If you don't then you may have a problem.

Kevin

[tippie53]

yes I am using the flat side to check the angle and to take the doming off the upper part of the body.

[kencierp]

Hi Logan,
This may help clarify a bit -- since it gets a zillion hits I know it has become a pretty standard read for scratch builders and for that matter kit builders.

http://www.kennethmichaelguitars.com/neckangle.html