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Hi guys

I am building an asymmetric wedge small jumbo of my own design and would like to fully profile the sides before bending.
I have made paper templates of the shape of the sides and I'm going to transfer these to 1/2" mdf. The mdf templates will then be used as a pattern to shape the sides/ribs.

My first thought is to saw close to the line on the ribs and then use a pattern router bit to create the profile, but my concern here is the tear-out of the sides.

My second idea is to again saw close to the line and then use a robo sander (don't actually own one) to create the profile, my issue here is that I sometimes use cocobolo and we all know how cocobolo clogs abrasives - especially if the sanding is concentrated in a 2 - 3mm band.

So my question to you is, how do you do it?
How do the factories do it if they don't have a laser cutter?
And also, how to hold the sides tightly on the template without clamps and such getting in the way, maybe double sided tape?

Thanks in advance.

Bob

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http://www.bobmatthewsguitars.co.uk

I usually have to do some sanding of the rim set after it is assembled and the neck and headblocks are in place.

I'm not sure exactly how you are going about the assembly, but if I understand your process correctly, and I were worried about tear-out with a pattern router, I would just use a climb-cut. It ought to work fine.

Lincoln

Bob: I think you are over thinking about doing the conturing.Use your template to mark your sides. Cut your side close to shape with bandsaw, bend,glue on your end blocks,then form your top and bottom radius with sandpapered dishs with the rims in your mold. I don't conture until I have the rims assembled. Just the way I like to do it. When you pre-conture you have to be a bit more careful when bending to make sure the bend locations are in the same place on both sides.
Tom

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A person who has never made a mistake has never made anything!!!

+1. If you contour it to final dimensions, you still have some radiusing to do even if just to level. You may then end up with sides that are narrower than you'd like. Also, no worries about tearout.

Oops, just realized you're talking about a wedge body.....ignore my comments.

Bob : Note to myself ....................Read the posts more carefully !!! Carry on folks. Thanks Beth.
Tom

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A person who has never made a mistake has never made anything!!!

A wedged back is still spherical, just on a slant, no?
So I think the previous advice is valid...

I left a least 1/8" extra on my side profile for the 5 Manzer style wedges I have completed and on my current project. I just trace my outline on the wood and saw the profile out and bend the sides. After the rim is assembled I sand to final side dimensions with my radius dish before gluing on the kerf cut lining. It only takes a few minutes to do the sanding, then after the linings are on I sand them back to the side heights, with the dish.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

I have to go with Fred and the others. I'd leave 1/8". By the time you bend, get it in the mold, get the top flat and reach your final profile with planes, sanding, whatever, you will be glad you had that little extra. At least I usually am

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Joe Beaver
Maker of Sawdust

I don't do it that way but if I did I'd probably reach for a spoke shave.

Thanks for your responses guys, I do normally sand in the dish but want to minimise this step as much as possible, so I will go with Lincoln's suggestion and climb cut with the router and a pattern bit. I'll let you know how I get on.

Bob

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http://www.bobmatthewsguitars.co.uk

Where did you get your patterns?