Help with arc/circumference measurement

[SHNOOGANS]

I am working on a project that requires an arc on a frame piece. The plans do not specify a circumference, only that all frame pieces use the same circumference. I figuerd a 20 degree will work (12 ft boat frame) begining 2" from center. Does anyone know how to measure this????:BangHead:

 

[SteveColes]

I am working on a project that requires an arc on a frame piece. The plans do not specify a circumference, only that all frame pieces use the same circumference. I figuerd a 20 degree will work (12 ft boat frame) begining 2" from center. Does anyone know how to measure this????:BangHead:

Rick, could you draw a rough picture, I'm not dutr I undrtstansd what tiy are trying to do.

 

[McRabbet]

Rick -- A "20 degree arc beginning 2" from center" needs more explanation -- If you provide more details, I'm sure we can get a set of measurements for you using CAD.

Rob

 

[vorlon666]

Circumference (of a 360 degree circle) = 2 x radius x Pi

If you have 20 degrees of arc with a radius of 2 inches,

C = 2 x 2 x 3.14159265 x 20/360 = about .69 inches.

Not sure if this is what you are looking for :eusa_thin , but the formula works for any radius or size of arc.

Steve