No 4 Motor Vibrations

Help! – our No 4 sounds like a freight train and can be heard two floors up.

Thinking the sound was possibly coming from the ink drum or chain, I removed the belt that connects the motor to the gear box, but no luck. The motor itself is quite (I disconnected it from the press and turned it on while it sat on the floor) but when attached to the press, it causes vibrations that make the metal cabnit resonate and the floor shake. The motor appears to be connected as per the diagram in the manual and the bolts that hold the motor base onto the underside of the gearbox have rubber washers.

Is anyone familiar with this problem? Would adding rubber to the points of contact where the motor/gearbox assembly attaches to the press frame help?

My suspicion is that the motor itself is to blame. When I’ve put my hand on it while it’s winding down, it feels as if the shaft is acentric – creating a wobble. The motor is a Dayton model 5K460A, 3/4 hp, 1725 rpm. Anyone have the same motor?

0 0 votes
Article Rating
Notify of
Oldest Most Voted
Inline Feedbacks
View all comments
Paul Moxon, Moderator
12 years ago

I say this press on May 21. The motor was the loudest motor I’ve ever heard. So as Chris said it will have to be replaced. There were the usual repairs: new form roller clutch pins, springs for the carriage latch spring and front trip wedge, LB-7 copper paper guides and the cylinder needed to be retimed. Other than that it’s a nice press and appears to have seen little use since 1948. It will be a great addition to their studio.

John and Nancy Johnson
12 years ago

Chris, We don’t have any vibration issues with our #4, only a little chain rattle. Maybe you can try mounting the motor back onto the press and disconnecting the chain from the gear box to eliminate the turning of the inking drum. If there is no vibration with the motor driving the gearbox but not the inking drum you would be narrowing down the areas of possible problem. Another thing you might check is the tightness of the chain. A really loose chain might cause some vibrations.

John and Nancy Johnson
12 years ago

The pulley you have matches what we have on our #4. Our motor/pulley is set up as yours is – there is a keyway on the motor shaft but not in the pulley, and a hex screw is tightened into the keyway of the motor shaft to hold the pulley in position.

Eric Holub
12 years ago

A square key is not a lead wedge. It is steel, and meant to fix the pulley to the shaft in alignment, without slippage. It is not meant to give.
I’ve had worn v-pulleys that cause just such vibrations, but the 4s I’ve seen all had flat belts from motor to gearbox. Still, running a pulley without the key can result in wear and eccentricities that cause vibration.

Paul Moxon, Moderator
12 years ago

Square keys are easy to get and the length can be cut, but you should measure it. I’ve seen motors on No. 4s from various manufacturers. This model was in production for 25 years.

We’ll discuss a visit via email.

Paul Moxon, Moderator
12 years ago

This will be hard to diagnose without seeing it in person. In an email you mentioned the this press (c.1948) had been neglected: “at one point the ink drum/well had caught on fire – leaving lots or caremalized ink in the tray. We also found a family of dead mice up inside the frame.” It could be that there is more ink inhibiting the chain/sprocket or that the gear-box needs more oil.

You say that the motor is quite on it’s own. The wobble could be caused by the absence of a square key to secures the pulley and the shaft. Are there notches on each part? These should align to fit a 3/16″ square bar. Still, you may need to replace the motor. Contact Grainer or McMasterCarr either should have a replacement.

My time in NYC is brief, but I could arrange come by before or after workshop at CBA.

Copyright © 2024 vandercookpress.infoTheme by SiteOrigin
Scroll to top
Would love your thoughts, please comment.x