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28" Ohio Heavy Shaper, DC drive motor questions...

Salem Straub

Cast Iron
Joined
May 22, 2012
Location
WA, USA
Hi everybody, I have an option to buy a big old shaper locally... it's an Ohio Machine Tool Shaper, Heavy 28" model. It appears to be all there, including the vise, and everything I tried on it, moved... I may be able to power it up when I go back to look again.

I know some of you have Ohio shapers, but I can't find much out there about them, especially not the 28".

It's got an electric drive system, the like of which I've not seen before.

The input is 3 phase AC, which first goes to a knife switch.
After the knife switch, the power goes to a line starter, equipped with momentary run/stop buttons.
From the line starter, an armored cable goes to the motor housing.
From the motor housing also comes an ever larger armored cable, which runs over and down along the side of the machine to a box about 14" square on the machine base, with a vertical square post coming out of the top, with a lever that rotates it. It kind of resembles a big switch. There is no arm from the machine that actuates the switch; it's apparently either an on/off or reversing, or speed control of some sort. It doesn't click into positions, rather it feels "infinite."
The motor itself appears to be DC - there is a three ring commutator on one end, at any rate.

I've not seen a drive like this, I can only guess that it's an early AC over DC electric speed control of some sort. It does not have a smaller motor belt driving the large motor, piggyback style like on some lathes I've read about.

Any of this ring a bell?

I haven't even been able yet to suss out what the AC input voltage is set up to be.

Thanks for any thoughts, I need an education on early electric drives!
 
That sounds like a wire wound rotor AC motor. Variable speed by using resistor banks or switches. Lots of torque.

Most common application was for crane motors before VFDs and Vector drives came into existence.
 
What Ziggy said.

DC of that era - if not from a DC generator and "distribution system" (common aboard some seagoing merchant vessels) was a tad on the massive side.

The 50 HP DC Niles at Galis, it was all in great boxes in a walk-in expanded mesh cage about the size of a suburban half-bath.

3-P in? Your unit is not typical DC. Either an MG or physically massive rectifiers were needed, pre "silicon" days.

Now the fun begins to find out just what ELSE it actually IS!

Motor and other goods maker names would help. Some of this stuff is published in old company history info online. Reliance was really good about that.

"Pictures", please! Data plates especially
 
I think you guys nailed it. That was fast! I love this forum...
i looked up "wire wound rotor AC motor" and found some articles explaining wound rotor AC motors, and how they were used widely for AC speed control before VFD's became dominant. The pictures show the slip-rings on the rotor and all, looks like what's on the shaper. The box with arm must be the speed controller, or wye-connected group of resistors.

That is excellent, thanks guys.

I'll likely be posting more about this machine in another thread, heck I'll come back and put some pics of the motor drive in this thread for posterity!
 
Make sure to maintain the brushes on the motor slip rings. They will arc severely and require re-finishing the slip rings if arcing does occur.
 
I'll likely be posting more about this machine in another thread, heck I'll come back and put some pics of the motor drive in this thread for posterity!

A HS bud was really into street railway cars & their museums and restoration. Got himself a proper "Motormans" license, and all. Boring to my "wannabee high tech" mind in the day.

And then I relocated to Hong Kong. Some of the 1903 tech was still in use.

Your drive IS "high tech" by comparison!

:)
 
Make sure to maintain the brushes on the motor slip rings. They will arc severely and require re-finishing the slip rings if arcing does occur.
This.

Take all the brushes out and clean them up, even if they feel like they're free in there.
Learned that the hard way a couple times. Laziness gets painful, quick.
 
Good to know. I did see that the slip rings appear to have smooth surfaces... the whole machine does not evince heavy signs of wear anywhere I could see, other than the clapper cross slide having been repaired in the past, probably due to a crash.
 
Can email 16" manual if you want to PM an address

Its all I have come up with that is even remotely applicable to my 1951 36"

Just plain jane AC motor though

ON EDIT - manual emailed
 
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