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rustyolddo
07-25-2005, 10:09 PM
Seem to recall an add on digital readout for spindle speed. Anyone have a source?

rustyolddo
07-26-2005, 10:55 AM
I found what I was looking for: http://www.camtronics-cnc.com/

hoagiem
07-27-2005, 02:50 PM
i did a search for digital tachs on the internet and found some interesting handheld tachs for hobby airplane props. maybe these could be modified to work or the spindle could have some relief cuts that the optical sensor could pick up. just a thought. good luck.

whelen
07-30-2005, 06:32 PM
Rustyolddo, I just ordered one from Little Machine Shop. It's meant for the SIEG mini lathe models. Although I don't know why. They come with a digital tach readout. Maybe the older models didn't. Chris Wood of LMS states "This tachometer is specifically designed for the 7x10 and 7x12 mini lathe. But people have adapted it to work on many different machines." Part number 1684, Tachometer, Spindle, includes interrupter wheel, sensor, and cable. "This spindle tachometer ... displays the speed, to the nearest 20 rpm."

I just purchased one for my SIEG X2 MicroMark, MicroLux milling machine #82573. I had it shipped to KDN Tool & Automation (www.kdntool.com). KDN Tool is converting my SIEG X2 - Microlux #82573 to full CNC. They will be replacing the gear drive (2,500 rpm max) with a belt drive (4,000 rpm max). And will wire in the tach output into the DeskCNC card, so that DeskCNC can be used to set/change spindle speed in the G-Code.

Whelen

ryanhathy
12-07-2008, 09:17 PM
I know this thread is old, but hopefully the idea I have will help people looking for a cheap tachometer solution.


i did a search for digital tachs on the internet and found some interesting handheld tachs for hobby airplane props. maybe these could be modified to work or the spindle could have some relief cuts that the optical sensor could pick up. just a thought. good luck.

I agree, I also thought about using an RC Airplane tachometer, all you would need to do is paint the spindle shaft white and then paint some black bars over the white around the circumference to mimic the prop blades blocking the light. You could also add an LED for a light source if external lighting is insufficient.

I didn't go through with the RC tach idea because I found that for only about $10 more, I could get a hand held laser tachometer which makes things super easy. You can get them for around $30 on Amazon and possibly less on ebay.

Amazon.com: Professional Digital Laser Photo Non Contact Tachometer - Accurate to 99,999 RPM Measurement Tool: Home Improvement

All you have to do is put a reflective strip on one side of the spindle on your machine. The tachometers usually come with a couple feet of reflector tape. The laser will reflect off the the reflector strip each time the shaft rotates around and bounce back to the optical sensor on the laser tachometer and it will use the pulses to calculate the RPM. That's what I use with my machine and it works really well. The nice thing about the laser tachometer is you can use it on more than one machine, along with pretty much anything else that rotates. Also, they can work up to almost 2 feet away from the shaft, you don't have to have it very close at all.

Crevice Reamer
12-07-2008, 09:41 PM
Another source:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=41727

About the same price when on sale, but I think yours is better.

CR.