• Congratulations to John K. Jordan winner of the June 2025 Turning Challenge (click here for details)
  • Congratulations to John Shannon"Cherry Bowl" being selected as Turning of the Week for June 30 2025 (click here for details)
  • Welcome new registering member. Your username must be your real First and Last name (for example: John Doe). "Screen names" and "handles" are not allowed and your registration will be deleted if you don't use your real name. Also, do not use all caps nor all lower case.

Turning off a Variable Speed Lathe

Brian Horais

Brian Horais

In Memoriam
Joined
Dec 20, 2014
Messages
249
Likes
1,848
Location
Knoxville, TN
Website
www.horais.com
How many of you turn your variable speed lathe down to zero RPMs before turning it off? I make this my everyday practice, but I have heard some turners just turn off their lathes with the on/off switch, independent of what the speed is set for. I like to know that my lathe will not be turning when I 'power up', so I set it to zero RPMs when turning it off. I think of this as a safety item. What are your thoughts/experiences?
 
You know Brian, I really never though about this subject until you mentioned it. I guess it is by habit that I always turn my VS to 0 rpm when I am finished for the day.
 
I'm a 'turn the pot to zero' guy. Goes back to my days in radio where I was taught to turn the pot down on my mic to avoid the switch pop from getting on the air.
 
I admire your discipline but must admit I just punch the button. I adjust the speed before I turn on again, but your way is clearly the safer one.
 
I just cut it off and unplug. I have noticed that the speed does not ramp so fast that even with my reflexes I can get to the speed control and change it. Now to qualify that statement if I have a larger blank I do lower speed before power gets turned on.
 
Mine doesn't go to zero, so it's not a choice. My brain only has room for a limited number of rules, so I always check the speed before turning the lathe on. That seems more important than what it is set to while it's off.
 
Another Nova DVR user, so different opperation. If the electronics are off (not just the motor) I have it set up to default to 300 RPM when powered up. I also have it programed to ramp up to speed over a second or two, so if it was last used at a higher speed setting it doesn't just blast off when I hit the start button.
 
I have trained myself to turn the lathe speed to zero before hitting the switch. I have also got into the habit of flipping the breaker off when not using for more than a few minutes. The box is right behind the head stock so easy to hit.
 
Not really given it much thought, but probably do both. But back in the "old days" you didn't have much choice, depended on how many many steps you had on your lathe's pulleys, it always start at a preselected speed.
 
Personally I'm in the habit of hitting the off button first and foremost whenever shutting down. I think it should be an instinctive reaction for shutdown. I'm in the camp where you turn the speed dial down prior to start-up. Just my habit.
 
My Rikon goes down to the minimum speed on the VS dial. I turn it all the way down so I don't mount a piece and start it at WOW! speed.
 
Whenever I teach I routinely inspect all the lathes for belt position and speed dial Fully counterclockwise.
also have the students check the belt position and speed.

I have a good friend who suffered a severe hand injury from a student’s bowl.
The class was NE Bowls. The lathes had reeves drives. The student had finished a bowl on a suitably high speed and mounted a new blank without turning down the speed. The blank shot up 12 feet before my friend who was rushing over could reduce the lathe speed. The descending bowl hit is hand. 20 years later one finger still doesn’t work right.
 
Great replies by everyone! I think we all have safety in mind when working around our lathes. Surprises can sometimes be very harmful, as you pointed out in your post, Hockenbery. I took a class once and pointed out my theory to the instructor on turning the lathe speed down to zero before shutting it down. He responded that he never does it because it will wear out the speed control. My view is that speed controls are replaceable (although I doubt the control will wear out), but body parts don't readily heal (if ever).
 
brian horais said:
Great replies by everyone! I think we all have safety in mind when working around our lathes. Surprises can sometimes be very harmful, as you pointed out in your post, Hockenbery. I took a class once and pointed out my theory to the instructor on turning the lathe speed down to zero before shutting it down. He responded that he never does it because it will wear out the speed control. My view is that speed controls are replaceable (although I doubt the control will wear out), but body parts don't readily heal (if ever).
Click to expand...
Yes, parts for antiques are even harder to find.
 
I just hit the off button. Most of my turnings are bowls. When I prep a bunch of wood, they are all different sizes. At start up, I turn the lathe on and have my hand on the speed button to adjust instantly as or if needed. I ALWAYS do this, on automatic. I did hear a story about Dave Ellsworth sending a blank through a wall at one of the early AAW Symposiums in Davis, CA years ago. If I am turning a bunch of pieces the same size, I don't check the speed....

robo hippy
 
brian horais said:
I took a class once and pointed out my theory to the instructor on turning the lathe speed down to zero before shutting it down. He responded that he never does it because it will wear out the speed control.
Click to expand...

And, using the lathe will wear out the motor, belt, power switch, bearings locking levers, tailstock crank, ........ :D

My first lathe had a Reeves drive so it didn't take too many missteps to do things the right way ... meaning turning the speed control down to minimum before stopping. For those who aren't familiar with Reeves drives, one of the idiosyncrasies is that you can't move the speed control lever unless the lathe is running. If you shut the lathe down with the speed control at maximum RPM and then mount a large heavy unbalanced blank things can be pretty exciting while simultaneously ducking for cover and lunging for the speed control. :eek:

My normal practice is to turn the speed pot down, but sometimes I just want to momentarily pause to check things out .... in which case I will just hit the stop button.
 
I usually turn the speed 'pot' way down to a slow rpm but not to zero. My old General 260 has a "Forward/Stop/Reverse" switch which I use while turning. At the end of the day I turn the speed down --- hit the red power off button (mounted on the inverter box) --- and then pull the plug from the wall. I do this in case there is a power surge or lightning strike that would fry my inverter or mess it up. Some of you may think this is overkill.....but I think of it as an insurance policy! :D Had the lathe for 24 years without any inverter problems.
 
John Walls said:
I have trained myself to turn the lathe speed to zero before hitting the switch. I have also got into the habit of flipping the breaker off when not using for more than a few minutes. The box is right behind the head stock so easy to hit.
Click to expand...

John,
Flipping the breaker off doesn't disconnect the neutral or ground wire in case of an electrical storm. It is safest to unplug your lathe when finished for the day. I heard of VFDs getting fried even when the breaker was off so I don't take a chance because it only takes a few seconds to unplug most lathes.
 
Thanks for the hint. At the moment, mine is hard wired to the box, no plug. When I get a chance this summer and make it to the hardware store I may put a plug end on to be safe.
 
The VFD's used on most lathes have accell, decel and minimum & maximum speed settings although many of the lathe manufactures apparently don't think turners should be able to access the settings. The VFD's on my lathes are units that I bought and installed myself and I set the accel, decel and the minimum and maximum speed as I like. My practice is to just hit the stop button or switch then when I am done for the day I hit the power switch. As far as starting at a high speed setting I have taught myself to turn the speed down to minimum when dealing with heavy out of balance turnings, but when working on turnings that are already balanced I leave the speed pot alone.
 
John Walls said:
I have also got into the habit of flipping the breaker off when not using for more than a few minutes.
Click to expand...

Circuit breakers aren't meant to be used as switches. Frequent toggling can lead to a breaker becoming "weak" ... meaning that they will trip at a much lower current than its rated current.
 
You must log in or register to reply here.
Back
Top