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View Full Version : Grellier back radius quesion



bigdog1002
02-06-2011, 02:10 PM
Hi,
I am starting by 1st build using the Grellier soprano plans. To make things easier I loaded the plans into Autocad and began to convert the measurements to inches. When I checked the radius on the back braces I saw that B1 has a radius of 13" and B2 has a radius of 37". I made a radius dish with a 15' radius on my lathe but it obviously wont work. Should I just use shims when gluing the braces to get the correct curve on the back or should I create another radius dish with smaller radius ?

Thanks in advance,

Eric

Bradford
02-06-2011, 06:35 PM
Hey bigdog, something does not compute. I can't imagine those small of radii being correct. A !5' radius is very common for a back, and 25' is a common one for the top.

Brad

Liam Ryan
02-06-2011, 08:17 PM
Eric, Grellier is not God. Although, he's pretty close in my opinion for putting those great plans in the public domain for free. Just radius the back braces to 15' then radius the ribs/linings to 15' then glue the sucker on. Coincidentally, I use 15' for all my backs. You can use pretty much anything. some use flat backs although I don't recommend it .