question about speed control

Yes, replace the single phase motor with a Variable Frequency Drive and a 3-phase motor.

Bill

AST> I have a Record Power (DML24X/C) lathe and in order to change the

LOL! Actually, replace the single phase motor with a 3-phase motor controlled by a VFD. :)

D

i would check on switching motors from an A.C which you have now, to a D.C (direct current) you will need a voltage inverter to do this but will give you total control without compromizing power and i would think cheaper than a 3 motor phase and phase converter ross

Ummmmmm...... Isn't that what I said?

Bill

Dan Boll>> Yes, replace the single phase motor with a Variable Frequency Drive

I think that Record makes variable speed lathes. Perhaps you could contact them re a VS add on for your model. Also I note that a "Speed Genie" for variable speed is advertised in Woodturning magazine. E-mail

According to the size of your lathe and what you are turning, the cost of converting to VS compared to the trouble of changing belts might not be feasible.

I don't know your lathe's motor drive design, but is there a way that you can vary the tightness of the belt to make a 'clutch' for varying the spindle speed? Perhaps by a lever to vary the motor--spindle pulley separation or by interposing an adjustable idler pulley.

Turn to Safety, Arch Fortiter

Well, the money spender methods have been offered. I have a lathe with pulleys, and find I _may_ change speeds once during a piece. Given that it can take me an hour for a bowl, the belt change represents very little of the total time. I spend more hunting down and changing grits of sandpaper. I can live with it. For me it's 680, which provides good service for pieces as small as finials or bowls as big as the 15.75 capacity over the bed. Only you can decide whether it's a significant factor for you.

I have a similar lathe sold under a different name. I replaced the bolt on the drive cover with a magnetic catch. I also reduced the belt tension. With these changes I found I could then change speeds in about 10 seconds. I recently bought a VS mini lathe and I find the VS's low speed is not as low as my belt drive, and the power is much better on the belt drive lathe. Brad

"Brad" wrote: (clip) I recently bought a VS mini lathe and I find the VS's low speed is not as low as my belt drive, and the power is much better on the belt drive lathe. ^^^^^^^^^^^^^^^^^^ If you change to a variable speed motor, you would be well advised to keep the the variable belt drive in place--you will have the best of both worlds.

Three phase motors are usually less expensive per horsepower than single phase or DC powered equivalents. In addition, some of the newer vfd's that utilize the new generation of solid state power switching devices are also less expensive as well. I think it is the more widespread use of three phase commercially that creates more power control options being designed to compete in that market due to it's size. A good selection of three phase motors I have found is

There are a number of ebay sellers who sell competitively priced, new electronic speed controllers for three phase, and single phase ac, 'plus DC controllers as well, sometimes matched with an appropriately sized motor.

Three phase power from the power company is Not a requirement to operate a vfd three phase motor controller as vfd's are available that use single phase ac input and provide three phase output to the motor.

Look for motors with a service factor ("SF" on the motor spec plate) that is greater than 1.0, like 1.15, etc. This indicates how much the motor can intermittently be driven beyond it's rated hp without risk of damage to the motor. The higher the SF the longer and more reliable the unit should be generally, usually weighing more due to more robust construction.

hope this helps someone out there...regards, Joe

PS: email me with any questions as I am sometimes not on the ng's on a regular basis....check mail at least every couple of days though.