C&P 12x18 with Motor Running WAY to Fast

I bought a C&P 12x18 a few months back, cleaned it up and turned it on but it’s running way too fast.

The motor is from the 80’s and is single phase and the person I bought if from said they were using it - but there is no way they were using it as is.

Any ideas?

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Can you post a photo of the press? Any chance it has a Horton Pulley on the shaft opposite the flywheel? Generally speaking motors will be a single speed unless there’s a cone pulley, rheostat, potentiometer, or variable frequency drive. You can reduce speed by decreasing the motor pulley size and/or increasing the press drive pulley size.

If you’re able to post a photo maybe it can be resolved without much trouble.

Bradley.

You may also check to see if the motor has a brush advance. It could be this was accidentally changed during transit. Look on the motor to see if there’s either a handle or a sliding plate at the end opposite the driveshaft. It will rotate around the motor’s centerline.

Adjustable brush advance is an older method of speed control on some single-phase motors. It physically shifts the brushes relative to the coils in the stator. The change in brush angle changes the motor speed. Generally, straight up is neutral and the motor will stall. Further away from neutral is faster. Some can even go either direction to reverse the motor.

These were once pretty common and are very easy to use, but also very energy inefficient. They also have the effect of reducing the motor’s torque dramatically as you reduce speed and they wear out the motor more quickly through brush wear and waste heat, so be careful with it if your motor has this. You’ll want to look for overheating from the waste electricity, or arcing inside the motor caused by carbon dust from the brushes.

If possible, I’d say replace the drive motor with a modern 3-phase and digital speed control. It’s so very nice and you can generally pick up a kit with just about everything you need on eBay for less than $200. I’ve done this on our Golding Jobber No. 7 and it made running the press so much nicer. I plan on doing the same to our 8x12 C&P next. It’s currently got its original 1950s motor with the brush advance system.

Michael Hurley
Titivilus Press
Memphis, TN

Michael, Would you post the search terms I can use on ebay for that kind of setup please, I’m thinking of something like that for my C&P

An image of the motor data plate might show if there is something else in the installation that requires attention.

Scott, look for things like “VFD with motor” or similar. VFD Is Variable Frequency Driver.

I believe this is either exactly the same or very similar to the package I bought when I upgraded the Golding:

https://www.ebay.com/itm/MOTOR-VFD-PACKAGE-1-3-HP-3600-RPM-TEFC-BROOK-MOTOR-WITH-50-HP-115V-TECO-VFD/362077056648?hash=item544d796e88:g:FrYAAOSw-zxWn-Jh

And here’s a video I shot when I got the motor running:

https://flic.kr/p/WWkLYK

One thing I should note is that the controller support arm I built has not worked very well. It was always a bit floppy, and I recently broke it off the press when I tripped and landed on it. The press and controller are both fine, it’s just the arm that got broken. I’m going to re-make it as a free-standing pole that I can move around and put out of the way.

One other thing I did was to put a fused switch in between the wall and the controller, just for extra safety. That’s the box next to the controller on the upper arm. The fuse is under the cover, above the power switch. Since our shed isn’t the greatest at keeping dry (especially in our rainy, humid southern climate!) I made sure everything is outdoor-grade and all connections are kept off the floor.

I think in total, including motor and controller with shipping, wiring, switch and box, and wood for the support, I was out no more than about $275-$300, and putting everything together took an afternoon.

Michael Hurley
Titivilus Press
Memphis, TN

Thanks Michael, that looks like a good solution. i have the original Kimble with shifting brush assembly, but the motor is in such neglected shape idk if I’ll be able to get it running. Where my press is located I can just attach the controller etc to the wall.
Always loved those Goldings, they look like they came from outer space.

Scott-
A trip to the motor repair shop for general cleaning & maintenance may be all the Kimble needs. And it’ll be a far better machine than a cheap modern motor.

BTW, the Teco VFDs are OK, but make sure you get one that will accept a single phase input if that’s all you have; not all VFDs will.

The Kimble is almost certainly rebuildable, but in this case I’m going to respectfully disagree with zbang. Most of the time older machinery is better built than newer stuff, but modern motors are generally built far better in most ways than vintage ones. Better understanding of motor physics, along with modern computational design means that modern motors are far more efficient and reliable. Just make sure you’re getting one rated for continuous industrial use.

Also, if your Kimble has brush advance it can only be single-phase. It cannot be speed-controlled as efficiently or as effectively as a three-phase motor. It doesn’t matter whether you’re using brush advance, rheostat, or VFD, speed-controlling a single-phase motor means reducing torque along with speed. Using a three-phase motor and matching VFD, you get full torque along the entire speed curve. This makes running the press at low speed SO much easier.

There’s certainly an argument to be made for refurbishing and maintaining the original motor to maintain overall originality for the press. I can completely understand that point of view and don’t have a problem with it. Just understand it will be harder to run slowly than a modern motor. It’s also may cost more to refurbish than to buy new.

It comes down to which is more important to you; ease of operation or originality. There isn’t really a correct answer.

Michael Hurley
Titivilus Press
Memphis, TN

To my surprise, after a couple of hours and a couple of cans of electric motor cleaner, the old Kimble runs fine. So I’ll probably put a set of brushes in it and look for a flat belt pulley for my 8x12 CP.

Scott- great to hear that. Since the motor pulleys were fairly small diameter (most I’ve seen are under 4-5”)*, if you’re handy you can make one by mounting a mostly-round wood block on the shaft and using that as a lathe. (Keep the sawdust out of the motor, though.)

* (do the math to check- desired impressions/minute * main shaft revs/impression = shaft speed, then work the flywheel/motor pulley diameters and mid-range motor speed)

Have you considered a step-down pulley setup on a mandrel between the motor and the flywheel? It’s a pretty inexpensive yet effective option. I was having the same issue on my 1898 old style. My motor was variable speed, but if I set it to a workable speed, it didn’t have enough torque to keep the press going.

To drop the press to a reasonable speed, I took an old mandrel from a bench grinder with a smaller pulley on one side and larger pulley on the other and set it between my flywheel and my motor. Now instead of one small pulley (on the motor) pulling one gigantic pulley (the flywheel), the small motor pulley (say, 3” diameter) pulls a medium pulley (say, 6”) which is attached to a mandrel with a smaller pulley spinning on the other side (smaller than the 6”, so something like 2-3”) which pulls the large flywheel. Adding these 2 pulleys of varying size on a mandrel will slow the speed while maintaining the torque (torque not being an issue in your case since the motor is single speed, but you get the idea).

I’ll attach a google image of an old lathe that uses a similar mandrel setup. You can get a new mandrel for $35 on Grizzly.com, or you can scare up an old one off a lathe or bench grinder.

I don’t have the press anymore, but I can post a photo of the original setup if I can find an image of it.

I’m not an engineer, so I just did trial and error to get it right. A step-down pulley with multiple sizes in one may help with getting the speed just right (there’s one in this image that the red belt is attached to).

image: image_44078.jpg

image_44078.jpg