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Jonas Mikolayunas
02-24-2022, 8:50 PM
Hey ya'll,

Requesting your wisdom to formulate a plan of attack.
I've designed an electrically driven contraption for top secret reasons. It includes a 1hp motor that drives a wooden drum (cylinder) via a 2-groove v-belt pulley transmission.

The Drum:


6" diameter x 10" length.
Constructed of 3/4" cherry discs cut with a cnc router, internally cross-doweled and glued up.
It will spend it's life rotating @ 1800 rpm



The Next Step:


I need to install a bearing in each end of the drum.
I need to install a 2-groove v-belt pulley on one end.
The pulley and drum need to rotate around a statically mounted 5/8" shaft.


The Problem:
I need the ends of the drum square with the face if I stand any chance at getting the bearings and pulley balanced and true. Never done this before.

Tools on hand:
Rikon 220-VSR Lathe
8" Cole Jaws
Carbide tipped tools
Steady Rest
Router Sled ('cuz it's cool)

Can I get there from here?

My gut tells me there will be a specific order of operations in getting all three surfaces true and square to one another.

I've experimented with lots of bearing and pulley types but I'm open to being smartened up.

p.s. - it's been so hard trying to get pulleys and sheaves to interface with the wooden drum that I've considered just extending the drum with a few oak discs and turning those down to be the v-belt pulley. Asinine?

Stay sweet

tom lucas
02-24-2022, 9:02 PM
Not exactly what you are doing, but I made a home-made sand-flea style sander using a big driver roller off of a conveyer belt system. I mounted it to pillow block bearings on each end with the pulley on the outside. I used a segmented belt. Got it as straight as I could with eye-ball and straight edge/square. Worked great. No wear on the belt/pulley at all. I don't quite get why it has to be so perfectly aligned.

Mark Hennebury
02-24-2022, 10:30 PM
True it up after the bearings and shaft are put on the cylinder.

Kyle Iwamoto
02-25-2022, 10:26 AM
Ummmm. 6" diameter piece of wood rotating it's whole life at 1800 RPM? Not knowing what you're doing, but I would guess that's a failure just waiting to happen. NO offense intended, but I'd use aluminum.

Dave Mount
02-25-2022, 2:20 PM
If your tolerances are that tight I would think that the ovaling of the wood drum through seasonal humidity cycling would be a problem. A wood cylinder turned true (round) today will not be true in six months unless it's in a tightly controlled environment.

Richard Coers
02-26-2022, 2:45 PM
Balancing the bearings and pulley? Surely you mean something else.

Jonas Mikolayunas
02-27-2022, 2:49 PM
Ummmm. 6" diameter piece of wood rotating it's whole life at 1800 RPM? Not knowing what you're doing, but I would guess that's a failure just waiting to happen. NO offense intended, but I'd use aluminum.
The drum is made of cnc'd discs that are cross-doweled and glued at every 45 degrees of rotation.

Jonas Mikolayunas
02-27-2022, 2:52 PM
If your tolerances are that tight I would think that the ovaling of the wood drum through seasonal humidity cycling would be a problem. A wood cylinder turned true (round) today will not be true in six months unless it's in a tightly controlled environment.
Think that would still happen with drum discs made with birch plywood?
Would marine plywood be a better option for this application?