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Any tips or hints on digging out my own radiused dish for gluing tops and backs. I can calulate the angle, but what or how should i use to route/dig/ or sand it out?

There are several approaches to making your own radius dish jig. If you do a search in the you will find several different ideas.Brad Way39110.6717824074

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Brad
Avon, OH

The jig I built to do dishes is eerily semilar to Ron's that he has a picture
of on the thread Brad linked. It was pretty quick and dirty, but gets the
job done. In terms of using it, the router obviously rides on top of the
rails. I plunged down at the center of the dish, rotated the dish under the
jig, and slowly worked out. One important note - make sure that the pin/
nail you use as the pivot point for the dish is lower than the router bit!!!

After routing, I ran the ROS over it to smooth things out. I used 3/4" C
grade plywood for the dishes and it worked surprisingly well. It's just
what I had around. If I was going to buy material, I'd likely buy MDF. For
the jig, 3/4 plywood for the base and poplar for the rails and spacers. All
screwed together so I could take it apart and salvage the pieces later if I
need to.

it is best to make the jig so that the radius rails are interchangeable to be able to try variouus radii. the easyest way to make the rails is to buy radius templates from luthier suppliers or lmi and use a pattern following bit to route them.

the radius templates come in handy for a variety of tasks.

I think you just answered the question I was going to ask, but let me be sure.

Thanks again for the pics, I was planning on a jig similar, and this made things more clear.

my dilemna, or confusion, is:

How do you guide the router to cut the precise radius?

Are you saying that the slots holding the router are arched at the designated radius?

Thanks again,

 

jon, see my post above.

That is what I was replying to,

 

so is that a yes?

 

Thanks

The rails have a concave arch in them - that is, the lowest point is in the
middle, right above where the center of the dish sits. You simply use a
straight bit in the router and let the router follow the curve on the rails to
create the curve in the dish.

here is a link to an archived discussion which has a couple of photos in it. there are many ways to do it.

   http://www.luthiersforum.com/forum/forum_p osts.asp?TID=3585&KW=radius+dish+jig#forumTop