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The radius dish from luthiersupply.com is finally here. So I took 4 pieces of sandpaper (they're so cheap here so I figure use it once and throw it... it's about a dollar for all four sheets compared to 20 dollars for a large enough sheet) and went at it. I had no idea that the waist area was going to be significantly higher on a 25' radius so I had to plane the heel and end block area until it matches and it's still taking forever. I should have done this earlier before the kerfing went on... I still got some distance to go before I stop seeing daylight at the waist. At least now gluing the top on should be a snap... all I need to do is place the top on the dish and the side on top of that and go bar on the back.

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Tai Fu my friend what I do which is pretty easy is to use a combination of methods to make the dish sanding much easier and quicker.

For the back of the rim/guitar the sides are pre-radiused using a method that Colin came up with where the actual radius is transfered from the dish that will be used for the back to the sides. Then the sides are cut out to match. With this method very little time in the dish is required. I can't find a link right now but will keep looking and post it when I find it.

For the top/front of the rim I shim the neck and tail blocks so that all that material does not need to be removed in the dish. Here is a link to how I do this: http://luthiersforum.3element.com/forum/forum_posts.asp?TID=9528&%20amp;KW=(pics)#forumTop%22

I like to keep the top side of the sides flat when bending and when gluing in the blocks so I can do it upside down, the rim not me...... , on a flat surface.

And it is helpful too to radius the rim, front and back, in the dishes prior to gluing in the kerfed linings. It's just a lot less material to have to sand through and then the linings can be added, 1/32 - 1/16th" proud and sanded in the dish to form the radius on them too.

Lastly I like 80 grit paper in the dish - things move along faster.

I hope something here helps.

Found it! Here is how Colin transfers the profile (back or front) directly from the dish to the side: http://www.luthiersforum.com/forum/viewtopic.php?f=10102&t=8117%22

Another point to keep in mind with this method of top/back radiusing, if you have a cutaway you'll need to make sure that the taper of the rim in the cutaway area is appropriately higher also, similar to the effect of the waist. The arch of the plate will cause the contact point of the cutaway to be 'in-board' of the rim area in the upper bout that would contact the top/back sans cutaway, if you know what I mean. Pardon the poor drawing, but this may help explain what I'm talking about.

http://bluescreekguitars.com/blog/
This is another method. It is a simple process but one that takes your building to the next level. Like Hesh I also do the sides then place the kerfing. It makes for alot less work
john hall

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
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