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For those of you with more experience with router collars, is it possible to use them to create a negative of a template? What I mean is, is it possible to use a combination of bits and collars to create a body mold from a body template?
Jason

Chris Paulick has a very good you tube tutorial on this. I have been using this method and it works well. Sorry I don't have the link

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http://goatrockukulele.com

Sure .. you just need to figure out the math .... from the original template, you are going to be routing away from it the bit plus the half the delta between the bit and guide collar. You want this to be a small number, so say we use a 3/8 guide and 1/4 inch bit .. so your total offset is now 1/4 plus half the delta of 1/8, which is 1/16 - total is 5/16. Now to use this new template to create a mold piece, you need to have the bit edge to be 5/16 inside the collar (or the bit to collar delta is twice this ) So if we need a delta of 5/8, use a 3/8 bit and a 1 inch collar or similar.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Yeah, I've seen his video and it's very informative. However, he shows how to create a gap. I'm looking to create inside or outside molds/templates that are negatives of each other.
Jason

Just be aware that you cannot do this if there are corners or sharp bends in the pattern.

You need to get a template guide kit to fit the base plate of your router. What you want to do is very common and quite simple. T

Another optionis the inlay guide kit .. it has an extra bushing that provides the offset to give the inner/outer dimensions in the correct value ... Lee Valley amd even Home Depot here in Canada have them ...

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

I've done this using bondo

First bass I built, first commision too, I had a mishap with the router, took a chunck out of the neck and fingerboard while nearing completion of the instrument.

What I did to fix this was:

1) create a smooth curve template, something like a section of an ellipse.
2) use this template with a pattern router bit, (the one with ball berring on the shaft) to give that nasty wound on the neck a smooth profile of the ellipse like shape.
3) Create a negative of the router template using bondo.
4) Use the negative template to route a patch piece from another piece of maple.
5) Glue them together.
6) As for the fingerboard, added binding.

Actually I'm amazed at how well the repair came out. You can tell it's there because the wood grain is different, and the way the maple reflects light too. but the fit is tight, and the customer still happy with instrument.

Another lesson, Don't take on commission jobs untill you've got the chops to pull them off!

Cheers,

Stefan

Thanks everybody. Those inlay kits from Lee Valley look pretty cool.
Jason