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Does anyone have the math formula for the angles to cut out pieces of a rosette, based on the number of pieces? I have seen it here before... I wrote it down but can't put my hands on it...
Steve

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

I have never cut rosette pieces but there are 360 degrees in a circle, basically all of the angles have to add up to 360 by the time you get around. I would look at each pieces having one angle (its second side belongs to its neighbor so 360/number of pieces.

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http://www.Harvestmoonguitars.com

30 x 12 = 360

12 pieces with 30 degree angle

or 30 pieces with 12 degree -

work on it using a piece of paper and see how it all goes together.

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

As simple as 360° / number of pieces you want.

If I want a rosette of 12 pieces, I know each piece will do 30°.

So I make a jig to cut each side of my pieces at 15°, here we go.

By the way, Alt + 0176 to do ° sign !

Francis

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Francis Richer, Montréal
Les Guitares F&M Guitars

I just realized I put this in the electric forum... whoops

Okay, I understand the angle now. I hate to be dense but, does each piece need to be cut a certain length?

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Steve Sollod (pronounced sorta like "Solid")
www.swiftcreekguitars.com

Well, you have to guess the width and lenght you need to fit into your rosette design. If it's not clear, cut these in paper before, you'll see right away. Also, don't bother you really with the length... Just make sure you cover the whole width of your rosette, and after, just cut the inside and outside circle with a router.

I just made a 12 pieces rosewood rosette this way, too bad I didn't take pics...!

Good Luck
Francis

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Francis Richer, Montréal
Les Guitares F&M Guitars

The length of the segments determines the diameter of the circle.

If your outer diameter of your rosette is 6", then 6Xpi = 18.84" is the circumference in inches.

If you are doing only 4 segments, then the length of the outer curved segment is 18.84/4 which = 4.71, for example.

If the length of each of the 4 segments is reduced by one inch, then 3.71"X4segments= 14.84" 14.84/3.14 then the outer diameter of the segment is only 4.7 inches.

So, you have to know the diameter of your rosette and the number of segments.

Course, I don't do it like the above at all. I just make a really thick rosette that is at least as wide as the outer diameter and then trim it to match the cavity. No math needed...

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"Building guitars looks hard, but it's actually much harder than it looks." Tom Buck