LMS 8.5 x 20

Jim,
It does have a separate small fan which I assumed (I know, I know) was to cool the electronics. Thanks for the education. (I hate it when I find out I'm not as smart as I think I am... again.)

MAE,
I got used to the pushbutton speed control pretty quickly and think nothing of it now. Hold the up or down button down and it will accelerate/decelerate smoothly. Short presses will increment the speed up or down by 10 rpm. I like being able to stop this lathe and then restart at the previous speed, in either direction. Handy for threading. My 7x14 had a speed control pot that had to be returned to zero to restart the machine after stopping it for any reason.

Tom
 
Thanks Tom. Does this thing stop on a dime when you hit stop. Just curious if it will thread to a shoulder. How did it come out of the box? Any complaints?
 
MAE,

It stops very quickly, but I wouldn't try to time it to stop tight up against a shoulder. Maybe a thread or 2 short and run it up against the shoulder by hand. I usually cut a relief groove to stop the tool in. Mine came out of the box darn near ready to run. A light clean up with mineral spirits, lubed it up and ran it. I took the top cover off and cleaned off the internal gears and lubed them with some spray on lithium grease, similar to chain lube. I don't know if a "break-in" is recommended or not, but I ran mine at 300, 500, 1000 and 2000 rpm for 10 minutes at each speed before I put any load on it. I figured it couldn't hurt. The more I use it, the more I like it. Hope this helps.

Tom
 
I haven't worked with the smaller BLDC motors like this, most of my work is in the 10 to 30 KW range. So I'm learning a bit here also. The controller theory is still the same.

One thought did occur to me, if the BLDC controller and the keypad controller are separate entities, then there may be an analog signal going to the BLDC controller, and it MAY be possible to manipulate that signal externally. This would require breaking the connection between the controllers and inserting some electronics between them. This could be as simple as inserting a pot. One would have to sit down with an oscilloscope and take a look at the signal to know how to approach the task. It could be a step pulse stream, a PWM signal, or it could be an analog voltage.
 
I thought about that, too, Jim, but I'm afraid of releasing the magic smoke from the electronics and/or the motor. I'm a EE, but on the power side of the equation. They have written text books about what I don't know about electronics. I know that for a fact because I used some of them for door stops in college.

Tom
 
That helps a lot thanks guys.

Tom, how accurate is the machine? Do you know the spindle runout? Again sorry for all the questions. There's a few lathes I'm looking at in this price range and I want to make the best decision. Plus it doesn't seem like there's too many owners of this particular lathe.
 
I thought about that, too, Jim, but I'm afraid of releasing the magic smoke from the electronics and/or the motor. I'm a EE, but on the power side of the equation. They have written text books about what I don't know about electronics. I know that for a fact because I used some of them for door stops in college.

Tom

You could possibly cobble up a 'translation circuit' between the hall-effect's feedback and the controller, but this could likely cause more trouble than it's worth. :)

What about making a back-gear for it? Don't know if it's even feasible, just throwing it out there.
 
Tom, how accurate is the machine? Do you know the spindle runout?

MAE, spindle runout on mine is .0006" in the center bore and .0005" on the register.


What about making a back-gear for it? Don't know if it's even feasible, just throwing it out there.

Bill, not sure about a backgear. But, did you check out the link I posted in message #2 above? That mod was done on a smaller machine than we're talking about, but offhand I don't see why it couldn't be done with a 8.5x20. I was impressed when I saw it.

Tom
 
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