Gold Dollar Bevel Angle

[Malort]

Hi everyone,

I'm playing around with some gold dollars. I've read the bevel angle is usually higher on these but the eight I have in front of me are all between about 15.5°-16.5°.


1) Is this consistent with what you guys have found?
2) Do you see a problem with how I measure this (below)?


2*(arctan((S/2)+W))

...where S is the thickness of the spine and W is the width of the blade, measured with calipers.

 

[bluesman 7]

2) Do you see a problem with how I measure this (below)?


2*(arctan((S/2)+W))

...where S is the thickness of the spine and W is the width of the blade, measured with calipers.

Yes, the width needs to be the ACTIVE WIDTH. This is from the edge to the furthest point that touches the hone. Usually the same place that you are measuring thickness. I find a clear scale to be an easy way to measure the active width without damaging the edge.

Also technically you should be using the arcsin as you are measuring the hypotenuse, but at these small angles the error of using arctan will be very small. A quick and dirty is thickness/active width X 57.3 = inclusive angle.

2 * arcsin .5T/AW where T is the thickness of the spine.

 

[Malort]

Okay, that makes perfect sense. Thank you!

I made a typo and meant 2*(arctan((S/2)/W)). I was using arctan because I wasn't measuring the hypotenuse like I should've been, but the entire width straight on, and getting much higher dimensions.