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Optical Tachometer


NEW! We have brought out a new machine mounted reflective optical tachometer. Low price great performance. Now with SFM



Site by: Digital Platinum


 How often have you wondered what the speed of your mill or lathe spindle was? How often have you wondered what the Surface Feet  per minute is?.If you needed to know you would have to lift the cover and look at where the belts were
orientated. Then you need to look it up in the manual or on the chart stuck to
the belt guard and try to figure out the setting. Next you would need to use a calculator to see what the SFM or in the case of metric SMM (surface meters per minute)  was compared to the chart speed and the diameter.  Then again there is always the problem that imported motors generally are 50Hz motors and when run at 60 Hz the speed is quite a bit different. Last, even if you have a hand held mechanical or
optical tach you then have to lift the guards to sense the spindle pulley.
Holding anything near those pulleys isn't safe while the machine is running.
In response to the above problem I have developed together will Alan
a micro controller machine mounted tachometer. It reads from 30-9999 RPM It uses reflective
optical sensors so there is no need to make a disk with a slot cut in it. Simply
place a piece of reflective tape on a flat non reflective pulley or if the
pulley is shiny place a piece of black electrical tape on the face of the spindle, bend the provided sensor  to fit your location
and install the display. As many of you know the RPM on the charts on a mill drill are not correct. The
mill drill that I have has the speeds for the both 50~ and 60~. Both are wrong
for the 12 speed positions on the pulleys. 
I ran some tests today using both the machine mounted tach and a handheld tach.
The chart for the lowest 60Hz speed showed 120RPM
Both the machine mounted and hand held tach read 173RPMs.
At 230 chart it read 286 at 440 chart actual was 497. At the highest speed the
chart said 2500 RPM , Actual speed was 2362.

Machine mounted Tachometer now with Surface Feet per Minute (SFM) or choose the metric SMM version 

About 14 months ago I introduced a Machine Mounted tachometer. The advantage of this tachometer over a hand held one is that it is safer to use, and always there. No need to check the pulley settings on the machine. It had another feature in that there can be two reflective sensors so a machine with dual motors can have their RPM checked with one tach simply by pressing a button. It has a sleep mode that when not being used reduces the current required. The one that I installed last April on my Shoptask has batteries that are now 6 months old and should last another 6 months.

            Since then we have add a SFM feature that will tell you the nearest SFM as well as the speed. You simply press one button to select the SFM reading you want. It works with both milling cutters and lathe stock diameters.  It can be set for 1/8, 1/4, 3/8, 1/2, 3/4, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10.  As far as I know there is no other tachometer that will readout both the RPM and nearest SFM. Best of all the prices for the tachometer will be the same. 

On the Metric version this feature works with both lathe and mills. The Metric Surface Meters per Minute scale for the following 3,5,8,10,12,16, 20, 25,30,50,100,125,150,175,200,250, diameters of millimeter cutters/stock. The Tachometer  provides the RPM and then as you select the diameter of the cutter/stock. The large LCD display shows the Surface Meters per Minutes