Calibrating Boss Spindle Speed

[snakebit95]

Hey Guys,
How did any of you calibrate/verify your Boss spindle speed? The reason I ask, is that the small round screen-printed plate that denotes the spindle speed is not keyed. It is simply held in place by a small acorn nut (by friction). I removed mine early-on in the retrofit process, and now have no idea what speed the spindle is actually turning. I do not have access to a tachometer or a stroboscope, so I need some other options.........or a suggestion as to where I can rent one of the scopes.

I am really not too worried about the plate being accurate. I am more concerned about my Mach2 software readout being in sync with the spindle speed. If I could measure the actual spindle speed and use the Mach2 input speed, I think I could calculate a pulley ratio to compensate.

Thanks,
Wayne

[Kevin Taylor]

Try backing the speed clear down then tighten the nut with the pointer on the slowest mark should be real close Kevin

[Hood]

get yourself a small slotted optical switch and a 220 Ohm resistor. then connect this up to an input to Mach and configure it as the index pulse (inputs page) Get a disc such as a CD and cut a 10mm x 10mm slot on the perifery of the CD. Put a bolt through the hole in the centre and chuck it into the spindle. When you turn on the spindle you should see the speed in Mach. Alternatively make it a bit more permanent by doing like I have
Hood

[snakebit95]

Hood,
That is a GREAT idea!! I thought about some type of hall-effect device on-top of the spindle, but was not ready to take it that far for a single use. After starting this thread, I found-out my father in-law has a tachometer he uses on his RC airplanes that I am going to try. I plan to mount 2-pieces of reflective tape 180° apart on a black tool-holder to simulate a 2-bladed propeller. If that does not work, I may go the route you did..........or just purchase one of the cheap laser tachs on EBay to try.

BTW.......how is the new lathe coming along? Is it running yet?

[Hood]

How do you control the spindle speed? I have a VFD but just use a pot to alter the speed, it is great to know the actual speed when altering the pot, and Mach is very accurate calculating the speed
The lathe is coming along, waiting for a few bits and pieces such as the encoders arriving from the states, should be any day now. I just got the PLC a few days ago and I am struggling to learn how to write the ladder but I am getting there so hopefully the first run will not be that far off.
Hood

[snakebit95]

I control the spindle speed via a VFD and a spindle speed controller card. Basically, I command the spindle speed via MACH2 MDI input (example is M3 S2500). With the adjustable pulleys up-top, I have no idea what ratio they are currently set at. I do not plan to move them once I have Mach and the spindle in sync.

Glad to hear the lathe is coming along. Learning new things is a lot of fun; especially if they are challenging. There are a lot of good jobs for people who know PLC's and ladder-logic. Keep-up the good work!!