Hotdog Rotary

Sun Apr 05, 2020

After several years of using the laser, I hooked up my hotdog-style rotary for the first time yesterday.

It seemed to be very easy to calibrate, so I wonder what all the fuss is about. I did have a look at The Manual, but I didn't follow it very closely. Maybe I missed something and I'll have problems in the future - feel free to let me know.

Here's what I did:
1. With the laser and controller powered OFF, I disconnected the Y-axis and hooked up the rotary.
2. I put in a random wine bottle (w/ no labels) to play with.
3. Per section 3.3.07, I READ the parameters, then set Enable Rotating to "Yes" and WROTE the parameters back to the machine. (I had already SAVED the parameters previously)
4. I drew a 3 x 3" square. When I did "Go Scale", I could see that the rotation was much to little. So I changed the Circle Pulse by a bunch to see if it would get better or worse. Per Murphy's Law, I chose the wrong way. Changing from 10,000 to 1,000 caused it to rotate even less. So I changed it to 20,000 and it looked reasonable. So I cut the square.
5. How to measure a round object? I took a piece of paper and wrapped it around the bottle. I marked the width of the square, and then measured it.
6. I could have adjusted the Circle Pulse, but I decided to mess with the "Diameter" setting instead. With a little experimentation (using "Go Scale") I figured out if I needed bigger or smaller numbers. Then I multiplied the Diameter by the error I had from my measurement. (E.g. the "square" measured 1.75" when it should have been 3". So it was off by 1.75/3 = 0.5833. So I multiplied the Diameter by 0.5833 and set that as the new Diameter.

7. Done. SAVED the parameters to a file.

Note that what I did will NOT work for a chuck-style rotary. The hotdog-style works by rotating the circumference of the object. Therefore, the actual circumference of the object is irrelevant. A chuck-style rotary works by rotating a particular angle around the axis. A rotation of 1 degree is a different distance depending on the diameter of the object.