I contacted David Brown at REBB Industries. I had read comments on PracticalMachinist.com that REBB still sold replacement A-100 Driving Rings. Dave confirmed that they did at a cost of $100 + shipping. Ouch. Still, since it's the heart of the variable speed drive and the variable speed drive is the heart of the press, I figured it was worth the risk to see if it would help.
I ordered one and in a couple of a weeks it arrived arrived.
So, time to take apart lower drive assembly and install the new ring.
I ordered one and in a couple of a weeks it arrived arrived.
So, time to take apart lower drive assembly and install the new ring.
While the drive ring assembly is apart, I might as well verify the sizes of the fasteners.
The 6-32's hold the A-128 Oil Retainer to the A-112 Drive Mounting.
The 10-32's bolt through clearance holes in the A-112 Drive Mounting into tapped holes the back of the A-100 Driving Ring. Looks like they could use a little cleanup before reassembly.
Olander must have been over on Commercial St. for a long time, given the condition of this relic. Can you even get a steel thread checker anymore? All the ones I see these days are plastic.
The 6-32's hold the A-128 Oil Retainer to the A-112 Drive Mounting.
The 10-32's bolt through clearance holes in the A-112 Drive Mounting into tapped holes the back of the A-100 Driving Ring. Looks like they could use a little cleanup before reassembly.
Olander must have been over on Commercial St. for a long time, given the condition of this relic. Can you even get a steel thread checker anymore? All the ones I see these days are plastic.
Drive ring assembly with all of the fasteners removed.
After removing the four 6-32 slotted screws, the A-128 Oil Retainer came off with a tap of the mallet (and a stout oak drift) from the underside.
I can finally see the A-129 Oil Retainer Gasket. It's a simple cardboard gasket between the Oil Retainer and the A-112 Drive mounting. Presumably this was intended to keep oil from the lube points on the drive mounting from getting up onto the mating surfaces of the A-100 Drive Ring and the A-104 Driven Cone.
After removing the four 6-32 slotted screws, the A-128 Oil Retainer came off with a tap of the mallet (and a stout oak drift) from the underside.
I can finally see the A-129 Oil Retainer Gasket. It's a simple cardboard gasket between the Oil Retainer and the A-112 Drive mounting. Presumably this was intended to keep oil from the lube points on the drive mounting from getting up onto the mating surfaces of the A-100 Drive Ring and the A-104 Driven Cone.
Side view of old A-100 Driving Ring (top) and then new one from REBB Industries.
The new one has an aluminum base vs steel for the old one. I wonder if the new (urethane?) one was cast or molded? The new one has the same thickness metal support ring (~0.375"), but the (urethane?) ring is ~0.750" thick vs. ~0.600" for the old black rubber one. Maybe when it was made, the old one was that thick, too! Between the compliance in the A-120 Coil Springs and the clearance in the slots of the A-8 Motor Plate, it shouldn't be an issue to get it fitted up properly. |
A-112 Drive Mounting cleaned up with WD-40 and gray Scotchbrite.
New A-100 Driving Ring ready for installation. Old driving ring not feeling the love. |
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Low speed run of the press with new A-100 Driving Ring installed.
Doesn't sound much better than the old one! |
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Medium speed run of the press with new A-100 Driving Ring installed.
Doesn't sound much better than the old one! |
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High speed run of the press with new A-100 Driving Ring installed.
Doesn't sound much better than the old one! |
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Close up of the gap between the A-112 Drive Mounting and the flange of the A-114-N Drive Bush with the press running.
Note the variation in the gap width. It looks like all the clearance and compliance in the drive ring assembly is just inherently rattly. Very disappointing. The A-104 Driven Cone and its assembly are rock solid in the A-2 Head casting. So the source of the noise must be either the motor or the driving ring assembly. I've run the motor on the bench and it's pretty quiet and well behaved, even when the driving ring assembly is installed on it. |
It like more work is required to figure out how to quiet this down. Maybe some sort of more stable from of compliance instead of the four A-120 coil springs? Combined with a bushing to reduce the slop between the drive mounting and the drive bush?
Time to give this situation some more thought. In the meantime, lets have a look at the belt tension assembly.