general 160 late vfd conversion project getting started

[Michael Schneider]

Hello All,

Thought I would ask for advice/wisdom thoughts for an upcomming project.


I am getting ready to convert my general 160 reeves drive lathe to a vfd.

I already have the vfd and motor (lenze actech and leeson 1 1/2 hp induction rated motor).


Basic Plans

swap motor and add vfd
add 110v outlet on lathe by vfd
Add a couple of e-stop switches in useful places


I am pretty comfortable with the motor and controller and have set it up off the lathe.

Some Questions:

Should I leave the reeve drive in place in the headstock or swap out? (still working fine)
Who makes a good pulley for the motor and what size ?



Motor info

Leeson 1 1/2 Hp Electric Motor 1750 RPM 230/460 Volt 3 Phase Inverter Rated

NtG Rise 30*C
HP 1.5 Duty Cont.
Code J Amp 4.2 / 2.1
S. F. 1.15 RPM 1750
Nom Eff 88.5 PF 74.9
Volt 230/460
Load type CT Inverter Type PWM
INVERTER RATED
Frame D90S Design 3 PHase
IP code IP55 Date 014F
IC code IC411 Alt 1000M
HP 1.5 KW 1.1
Code J Amps 1450
Nom Eff. 85.5 Cos O/ 74.5
Volt 200/400
SpeedRange 3-60HZ Weight 35Lbs. 15.9KG



Just curious if any of you have done a similar project and if so, any tips for things that worked well, or things that did not.

Thanks
Michael

[Dennis Ford]

I have done three similar conversions, two had the reeves drive left intact, on one the reeves drive was replaced with a step pulley setup. Leaving the reeves drive intact provided an efficient method of getting maximum torque at low speeds. One of the two that kept the reeves drive was a very old (and built like tank) lathe with a very high quality reeves drive, it was smooth and quiet. The other was a fairly old delta, it worked well but was noisy. The one that got a step pulley was also an old delta, it operates quietly. I think the owner uses the slowest ratio almost exclusively.

Most turners will need a mechanical ratio change in order to get good torque at low speed and a high speed good for small spindle type work. If your reeves drive is in good shape, keep it and install a motor pulley about the same diameter as the one on your old motor. Replacing the reeves drive with step pulleys (2 or 3 step) is a viable solution but it does add to the cost since you need two step pulleys and a new belt. It does eliminate one belt and several moving parts so will be less noisy. Finding step pulleys with bores to fit your shafts and a ratio that works for you will take a little measuring and research.

[Larry Copas]

I did a Rockwell 12” lathe with step pulleys last year. I mounted the VFD high so I could easily see the readout and vary the speed on the VFD pad. Since I had been using a Oneway 12-24 I copied that layout. I got tired of reaching across the lathe to use the VFD pad so bought and installed a remote pot. Hundreds on eBay starting at 99 cents. I waited until I found a made in the USA NOS AB pot. When I added the pot I went ahead and added a reverse/off/forward switch. I was worried about accidentally hitting reverse at full speed but the way my VFD is optioned, the lathe gently slows to a stop, than goes to reverse. No drama at all. My motor is a Baldor 1140 rpm 1 ½ HP mainly because it was laying unused in my rathole. I normally leave the belt on the next to highest speed step. Go from 25 rpm power sanding to wide open. It has worked flawless and I really like it.

I also wired in a two outlet box as you are contemplating. Its a good idea and I use mind quite frequently. While wiring, go ahead and put in a master on/off switch.

I picked up a low usage General 260 a few weeks ago with factory VFD. My first experience with a General and so far its great. You will really like your upgrade.

[Dick Strauss]

If you have a heavy duty cast iron reeves drive that is in good shape, I would keep it. If they are pot metal like the ones on the Griz/Jet/HF/Delta, etc, I would convert them to step pulleys.

I converted my Delta 46-715 1440 lathe. I replaced the stock 1hp 1725 rpm motor with a Leeson 1.5hp 3ph 1140 rpm motor so I actually have greather than 2x the torque I had with the old motor. Because the motor had been in storage for 5+ years, I had to replace the motor bearings before I could really use it because they were kind of dry when I tried it. One of the reeves pulley sets actually broke and was no longer available. So, I also replaced both stock reeves pulley sets with Maska/Baldor 4/3/2 cast iron step pulleys (from ElectricMotorSite.com) and bored them to fit the stock spindle shaft and motor shafts. The new step pulleys give me speed ranges of roughly 20-650 (using the 2/4 ratio) , 40-1350 (using the 3/3 ratio), 75-2650 (using the 4/2 ratio) using 2-70Hz on the VFD settings. I always build my control boxes (with magnetic attachment) that contain an e-stop button, speed pot, and for/stop/rev switch. Depending on the job and tool, the best/safest placement for the controls may change. I like the magnetic control mount so I can attach it to the tool where it is most convenient and safe for that one job.