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Lathe VFD?

Susquatch

Susquatch

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I've been busy deciding on a VFD for two mills that I recently purchased. In the process, I realized that such a device might be a good thing to add to my lathe too. My lathe is a 12x40 enclosed gear head with a single phase 220V motor. The lowest speed on the lathe is 70 rpm. But there are lots of times when I would like to be able to run it at 50rpm. A VFD would facilitate that and add other speeds too!

Is this a good idea or a bad one? Anything I need to know or watch out for?
 
That's a new one. I thought VFD's could operate on single phase. Snookered AGAIN!

I think you misunderstood my other post. I am running it with a ground. However, I am not running it with a neutral. My whole shop was wired by the previous owner with single phase 220 with no neutral. Which is ok if it's for welders and other devices that don't require one.
 
VFDs do operate on single phase.
They take single phase 110v or 220v and turn it into 3ph power which necessitates a motor swap to a 3ph motor.
 
John Conroy spent a while converting his 1PH 220V 14X40 lathe to 3PH VFD. It can be done, but a mill is far easier, and the place to start.

If, after successfully converting your mill to 3PH, you will be better equipped to consider a VFD/3PH conversion...
 
Dabbler said:
John Conroy spent a while converting his 1PH 220V 14X40 lathe to 3PH VFD. It can be done, but a mill is far easier, and the place to start.

If, after successfully converting your mill to 3PH, you will be better equipped to consider a VFD/3PH conversion...
Click to expand...

I like the way you think. I'll wait to see how the mill goes first.
 
Resurrecting an old thread. Seems I work at the speed of smell..... Maybe a lot slower than that!

After 2 years of looking, I have given up trying to find a used 3 pH 3hp motor for my lathe. So today I broke down and ordered a new 2.4HP one for just over $700 and just over a grand with tax and $$$$hopping. Wow...

Why so difficult? Long story but mostly frame Size, VFD Rated, 24mm output shaft, has to fit my existing 2HP motor envelope.

I had wanted a 3hp to deal with starting current, but settled for 2.4. Maker after maker after maker told me nobody makes a 3hp with that frame and size envelope.

The new 2.4 is also only 10:1 turndown, and 50% upper limit so 6Hz to 80Hz. But that is more than enough to satisfy my goal to have a 45rpm low speed vs my current 70. And no fan is needed for cooling. I'll still use the gearing and fine tune with the VFD.

When it arrives, I'll make sure it fits, and then begin the next phase of this adventure - converting the single phase control system to 3 phase with a VFD. Then a DRO!
 
Susquatch said:
Resurrecting an old thread. Seems I work at the speed of smell..... Maybe a lot slower than that!

After 2 years of looking, I have given up trying to find a used 3 pH 3hp motor for my lathe. So today I broke down and ordered a new 2.4HP one for just over $700 and just over a grand with tax and $$$$hopping. Wow...

Why so difficult? Long story but mostly frame Size, VFD Rated, 24mm output shaft, has to fit my existing 2HP motor envelope.

I had wanted a 3hp to deal with starting current, but settled for 2.4. Maker after maker after maker told me nobody makes a 3hp with that frame and size envelope.

The new 2.4 is also only 10:1 turndown, and 50% upper limit so 6Hz to 80Hz. But that is more than enough to satisfy my goal to have a 45rpm low speed vs my current 70. And no fan is needed for cooling. I'll still use the gearing and fine tune with the VFD.

When it arrives, I'll make sure it fits, and then begin the next phase of this adventure - converting the single phase control system to 3 phase with a VFD. Then a DRO!
Click to expand...
Who did you order from?
 
Susquatch said:
Resurrecting an old thread. Seems I work at the speed of smell..... Maybe a lot slower than that!

After 2 years of looking, I have given up trying to find a used 3 pH 3hp motor for my lathe. So today I broke down and ordered a new 2.4HP one for just over $700 and just over a grand with tax and $$$$hopping. Wow...

Why so difficult? Long story but mostly frame Size, VFD Rated, 24mm output shaft, has to fit my existing 2HP motor envelope.

I had wanted a 3hp to deal with starting current, but settled for 2.4. Maker after maker after maker told me nobody makes a 3hp with that frame and size envelope.

The new 2.4 is also only 10:1 turndown, and 50% upper limit so 6Hz to 80Hz. But that is more than enough to satisfy my goal to have a 45rpm low speed vs my current 70. And no fan is needed for cooling. I'll still use the gearing and fine tune with the VFD.

When it arrives, I'll make sure it fits, and then begin the next phase of this adventure - converting the single phase control system to 3 phase with a VFD. Then a DRO!
Click to expand...
And now you know why I ordered an AC Servo with the same power rating as my 2HP single phase. AC 3 phase and VFD were $300 more than the AC Servo.

Up side way quieter and RPM down to effectively 0 with full torque. When I finally get around to a toothed belt drive for it the noise will increase but then I can use the motor encoder for spindle feedback. For now I have 60 Teeth per rev or 240 PPR and can power tap really nicely.
 
You'll luv the VFD.
I was skeptical before I installed mine but now I'm a convert. Being able to tweak the rpm at any stage of a cut is such an advantage over having to stop and change gears.
 
jcdammeyer said:
And now you know why I ordered an AC Servo with the same power rating as my 2HP single phase. AC 3 phase and VFD were $300 more than the AC Servo.
Click to expand...

I thought long and hard (countless sleepless nights too) about that option. Ultimately it was my age that convinced me otherwise. My wife might have to sell it tomorrow and I didn't want something that buyers would shy away from. I want buyers to all be screaming "Start The Truck" no matter what their level of expertise.

YotaBota said:
You'll luv the VFD.
I was skeptical before I installed mine but now I'm a convert. Being able to tweak the rpm at any stage of a cut is such an advantage over having to stop and change gears.
Click to expand...

Would not take much browsing this forum to know that I'm on your page. After all, I've been looking for two years. That's gotta scream "Boy that ugly old man must really love 3ph and vfd!" @Dabbler was the guy guilty of pushing me over that cliff - without a rope! Never looked back. No point, it disappeared in the rear view mirror 5ft down.
 
I did this video right after I converted my lathe. It shows the speed changes possible in the range between 60hz and 10hz which are the max and min I have set up in the vfd. Ignore my speed estimate mistakes, 15hz give about 300rpm and 10hz about 200. I love this conversion, the ability to change speeds on the fly is a game changer.

johnconroy.smugmug.com

GH1440W Lathe - John Conroy

This video hosted by SmugMug; your photos and videos look better here.
johnconroy.smugmug.com johnconroy.smugmug.com
 
Susquatch said:
Resurrecting an old thread. Seems I work at the speed of smell..... Maybe a lot slower than that!

After 2 years of looking, I have given up trying to find a used 3 pH 3hp motor for my lathe. So today I broke down and ordered a new 2.4HP one for just over $700 and just over a grand with tax and $$$$hopping. Wow...

Why so difficult? Long story but mostly frame Size, VFD Rated, 24mm output shaft, has to fit my existing 2HP motor envelope.

I had wanted a 3hp to deal with starting current, but settled for 2.4. Maker after maker after maker told me nobody makes a 3hp with that frame and size envelope.

The new 2.4 is also only 10:1 turndown, and 50% upper limit so 6Hz to 80Hz. But that is more than enough to satisfy my goal to have a 45rpm low speed vs my current 70. And no fan is needed for cooling. I'll still use the gearing and fine tune with the VFD.

When it arrives, I'll make sure it fits, and then begin the next phase of this adventure - converting the single phase control system to 3 phase with a VFD. Then a DRO!
Click to expand...

What is your frame size? I have lots of 3ph 3hp motors.
 
Susquatch said:
Resurrecting an old thread. Seems I work at the speed of smell..... Maybe a lot slower than that!

After 2 years of looking, I have given up trying to find a used 3 pH 3hp motor for my lathe. So today I broke down and ordered a new 2.4HP one for just over $700 and just over a grand with tax and $$$$hopping. Wow...

Why so difficult? Long story but mostly frame Size, VFD Rated, 24mm output shaft, has to fit my existing 2HP motor envelope.

I had wanted a 3hp to deal with starting current, but settled for 2.4. Maker after maker after maker told me nobody makes a 3hp with that frame and size envelope.

The new 2.4 is also only 10:1 turndown, and 50% upper limit so 6Hz to 80Hz. But that is more than enough to satisfy my goal to have a 45rpm low speed vs my current 70. And no fan is needed for cooling. I'll still use the gearing and fine tune with the VFD.

When it arrives, I'll make sure it fits, and then begin the next phase of this adventure - converting the single phase control system to 3 phase with a VFD. Then a DRO!
Click to expand...

There's one in the Edmonton FB marketplace. I was going to pick it up to have it around but not sure if I would ever use it. lol

https://www.facebook.com/marketplace/item/1383653685754506/
 
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