Hypothetical question: VFD Motor on Hercus 9” and removing pulleys

[Dave022]

I have a Hercus 9” Model A that I am going to restore. The trouble I have is limited space. I understand that the pulleys allow higher torque at lower speeds. But would it be possible to use a 1.5 KW motor for example, and remove some pulleys whilst still generating high enough torque?

 

[Chipper5783]

Yes. Your question of "will it still generate enough torque?" is a bit like asking if a truck is strong enough to carry that much weight. It obviously depends on how much weight and how much truck.

You should be able to calculate the amount of torque developed based on the original set up and compare that to your proposed set up. How much derating you'll accept is up to you.

 

[Ulma Doctor]

1.5kw is plenty enough hp & torque for a 9" lathe.

i have a 3/4 Hp (.559 Kw) motor on my Hercus ARH 922.
it makes all but the very deepest cuts just fine with the OEM gearing and pulleys.
you won't have to change anything

 

[Dave022]

Looked at the motor plate today and it says that it is 115V, in NZ we are on 240V how would this be possible?

 

[JimDawson]

Looked at the motor plate today and it says that it is 115V, in NZ we are on 240V how would this be possible?

That motor is a dual voltage also capable of running on 230 volts. It's probably wired for 230 if you got it locally. But it is a single phase motor so running on a VFD is not possible.

 

[countryguy]

I ordered a nice Alu. frame WEG motor a few year back. This allowed me to get into a VFD rated motor w/ a constant torque (CT) and make it run w/ the VFD the way it should. Price wise, it even very reasonable. They have sales engineers that are bored and like to talk about some of the different hobby stuff. Mine did anyway. Call them to assist! Engineers love to chatter on don't we. ....ask my wife.

 

[Dave022]

Thank you, realised that this couldn't be VFD; obviously didn't read the plate properly. I will look into the WEG motor. Originally I was wondering if I could remove the countershaft assembly to save room but I think I can see the advantages of VFD anyway; especially if I want to cut metric threads on my imperial machine

 

[12bolts]

Have you considered a DC motor, (think treadmill) and go from there. Bulk HP in a small package. Max torque at zero RPM. All you need is a variable DC supply. Which coincidentally, your run of the mill treadmill already has installed as standard OEM

Cheers Phil