Bill M's Pm1340gt Setup

Hey Bill, looking good. Be sure to note/measure the distance to the optical sensor to the reflective markers, as it is quite important to for consistent readings. I also had problems when I grounded the shield in the cable going to the optical sensor, picked up the VFD noise. I ended up leaving the shield not connected at both ends. MacTach is very stable, and nice to have the SFM readings,
 
wrmiller19 said:
It's alive! :)

View attachment 104882

Now I just have to fab a mount for it and the sensor.
Click to expand...

MAJOR COOL...

As Brooks says... mine is still in the box...
And it probably will stay there for a while...
AC season is just too good (so far) this year.
The thing about being self employed... is you make up for the lean years... by working too many hours in the good years... :cool 2:
 
mksj said:
Hey Bill, looking good. Be sure to note/measure the distance to the optical sensor to the reflective markers, as it is quite important to for consistent readings. I also had problems when I grounded the shield in the cable going to the optical sensor, picked up the VFD noise. I ended up leaving the shield not connected at both ends. MacTach is very stable, and nice to have the SFM readings,
Click to expand...

So what did you end up with for sensor distance?
 
Too close or too far and it will error. I started with the optical, but switched to a use a hall sensor. Per the manual for the optical pick-up, they recommend 0.15-0.20". If your RPM is erratic, then you can try to tweak the distance. You also need to set the number of reflective strips (or magnets) per revolution. I found the RPM measured to be very close to the stated RPM on the lathe for a given gear at 60Hz. I have almost no variation/change in RPM once set, even under load. So the VFD does maintain the speed well.
 
Ok, thanks. I am going to try using the IR sensor as well, but bought the hall effect sensor just in case. How did you mount the hall effect and magnets?
 
Hall sensor/optical sensor mount uses the same base secured to the head by a single mounting screw, just that the hall sensor was epoxied to a small adjustable aluminum slide, there is a notch at the end that just fits the hall sensor. I machined an optical toothed gear, but embedded magnets in the teeth at a later point. If I where to do it again, I would machine a plain round aluminum ring drill shallow holes for the magnets and epoxy them in. I would use metal epoxy which is stronger than the standard stuff. I use 3 small set screws to hold the ring in place.

Lathe Hall Sensor.jpg
 
Couldn't get the IR sensor to switch below about 3.5v Adjusted the sensor distance and angle as well as the trim pot. Nadda. Don't feel like it right now, but will probably wire up the hall effect and give it a try. Right now I'm just tired of messing with it.
 
wrmiller19 said:
Couldn't get the IR sensor to switch below about 3.5v Adjusted the sensor distance and angle as well as the trim pot. Nadda. Don't feel like it right now, but will probably wire up the hall effect and give it a try. Right now I'm just tired of messing with it.
Click to expand...

Maybe pull it low with a pull down resistor? Maybe the load has too high impedance, I've had to do this with inputs on occasion.
 
And finally mounted and working. Took a few days of back and forth with Henry to figure out a wiring mistake in the documentation. I of course, followed it to the letter. But all better now.

DSCN4332.jpg


Didn't get fancy with the mount, but I did make it so I could adjust it up or down and rotate it if necessary.

DSCN4333.jpg
 
Bill if your ceiling ever collapses don't worry the DRO bracket will hold it up dang lol. Congrats glad you got this all working now, its been quite the project I have enjoyed this thread.
 
You must log in or register to reply here.
Back
Top