Trying to sell my old Seneca lathe. One minor sticking point is that I seem to have lost the "rocker" that goes under the tool in a lantern-style tool holder.
I want to try and make one, but wasn't sure about the geometry. I have the "cup" that the rocker sits in, so I was able to determine with some degree of accuracy the length (chord) and depth (height) of the arc. All I needed to know was the diameter of the circle that the arc was part of.
Turns out it's dead simple if you review some circle theorems from high school Plane Geometry. A couple of YouTube videos 'splaining it and I now know just how big a circle I need to turn to cut the rocker/arc out of.
In other news, I screwed myself...again...on a McMaster order. I really, REALLY need to pay more attention. A .505 reamer (which is what I wanted) is MUCH bigger than a .0505 reamer. Guess which one I ordered...
I want to try and make one, but wasn't sure about the geometry. I have the "cup" that the rocker sits in, so I was able to determine with some degree of accuracy the length (chord) and depth (height) of the arc. All I needed to know was the diameter of the circle that the arc was part of.
Turns out it's dead simple if you review some circle theorems from high school Plane Geometry. A couple of YouTube videos 'splaining it and I now know just how big a circle I need to turn to cut the rocker/arc out of.
In other news, I screwed myself...again...on a McMaster order. I really, REALLY need to pay more attention. A .505 reamer (which is what I wanted) is MUCH bigger than a .0505 reamer. Guess which one I ordered...
