Official Luthiers Forum!

Hi everyone,

I was hoping some you smart guys or gals can make some radius arcs - to help shape the braces.

I tried the ruler thing - flexing it - but I am not happy with the results - I want a template I can just print out and glue to a piece of wood and then shape the wood with the template.

For my back braces I need a 11' radius, and 8' radius, and a 20' radius

Or is there a program that can do this for me - so I can print out the arcs segments as needed ?
Seems so simple - but I can't find anything -

Thanks in advance !

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It's this new idea from recent decades that everyone gets a participation award. - MUX

better yet - can someone create a PDF that has all the common arc radius' all on one page ?
So as someone needs it - he or she can print it out and cut out the arc they need.
Even if it has to be printed on 11x17" paper - it would be useful, or if you can tape together a few sheet of 8 1/2" x 11 paper that would work too.

I was thinking - if you print the arcs in landscape mode - you can get more of the length on there - it would be useful to have a center line on the arc too.

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It's this new idea from recent decades that everyone gets a participation award. - MUX

John - Could you use a steel measuring tape with the end pinned to the floor and a marking knife or pencil secured at the various radii?

BTW, I have used the free version of Google SketchUP, a 3D modeling program to model most of the geometry on the guitar. Arcs are very easy. There’s a slight learning curve for the program of course, but it comes in very handy.

Joe

A piece of string, a nail and a pencil works good too.

I thought of that but it would be useful for lots of people to have a siple pdf to print with various arcs.

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It's this new idea from recent decades that everyone gets a participation award. - MUX

Or you could order some of my radius gauges here:
http://www.luthiersuppliers.com/products/p7.html

With these you don't need to print anything. Just place it on the wood and trace the arc with a pencil on the brace. These are convex and concave on each side. Good luck!

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Tracy
http://www.luthiersuppliers.com

John - I could create a PDF with those radii. I will do that and post it shortly.

Here you go John. This is scaled for 11" x 17" so it will need o be printed on that size paper in order to be accurate.

Thanks Charlie

And LuthierSupplier, that ia also a good idea and alternative

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It's this new idea from recent decades that everyone gets a participation award. - MUX

Oops...I somehow missed LuthierSupplier's response. Their templates are definitely the way to go if you don't have CAD and want a high quality template that can be used over and over.

The tape rule or string method is not very accurate in my opinion, I have a set of templates and they are a great tool.

Fred

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

It will be within a few thousandths properly done Fred, which would be as close as cutting it from a piece of paper. Plently accurate for at least my purposes

http://gicl.cs.drexel.edu/people/sevy/l ... mpass.html

replace the pencil with a router and you can very accurately make your own templates. i did. or just use the method to draw the arc. its the best method ive come across. short of someone else making them with a CNC, that is. that, of course, costs significantly more.

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sweat the small stuff.

Per John's request, I have added 3 additional radii to the attached PDF.

Charlie-
Thanks for those files- very useful.

Steve Senseney produced a similar .pdf which is accessible from the MIMF library.

You can get it printed full size at any place that has a large format printer, or use it to lay out your large radius template, or check the results from a long compass layout.

Cheers
John

My pleasure, John. I like the fact that Steve's file includes the offset measurements, which is a good idea. Thanks for posting it.