Think cheap/aluminum round bar

I’m looking for 3.5” or larger aluminum round bar. I only need 6” long. I’ve tried those online metal places and and and I’m not giving $75.00 for this.
I’m making a 3.5” by 6” long flat drive pulley.

Why aluminum? Is a little soft even for flat belt. Steel pipe welded to a central spindle would be stouter.

DMiller wrote: Why aluminum? Is a little soft even for flat belt. Steel pipe welded to a central spindle would be stouter.

The plan calls for aluminum but I’ve given the pipe on a hub lots of thought.
It goes on the shaft of an electric motor and turns a rubber tires drive wheel.
The 3.5” is somewhat important for proper RPM.

Drink lots of beer and get the smelter going.

Any good scrap yards in your area?

Tbone95 wrote: I wouldn't call 3.5" x 6" "scrap".  That's a pretty valuable piece.

Edited by Layne - 20 Dec 2018 at 1:30pm

jaybmiller wrote: OK I can't 'see' how a 6" long metal pulley will attach to a std electric motor. Most only have at most 2" of shaft. Having 4" of spinning metal at 1725 RPM is, well, a recipe for 'oopsy !!' Something about mass, inertia, and them physics things we never really studied too hard... Have to ask what's the HP of the motor ? I'm thinkin ghtis is for the forgling hammer gizmo ?? Jay

Yes it’s for the power hammer. It’s a 1 hp 1725 rpm motor. If it’s made proper I don’t see why it wouldn’t stay put. Key way and set screw hold it in place.

allis g wrote: at those RPM's you'll have to get it balanced on a dynamic balancing machine or it will destroy itself.

Well the one thing we have in little ole Busch Arkansas is an engine balancing machine shop and as luck would have it he’s one of my closest friends. Maybe I’ll just have him machine it as well and I’ll be working n something different at that time.
The engineers that designed this never made mention of balancing it. I wonder if all those I’ve seen in the hundreds of videos were balanced???
Other parts are definitely required to be sent to the balance shop. I appreciate the concern.

The heavy mas isn’t spinning 1725 rpm only the motor and this aluminum flat drive pulley. Picture it as a clutch. You step on a pedal which raises the motor til it touches a 30” is rubber tire. 3” against 30” is serious reduction and then one must figuare the built in slippage which means the tire will most often never meet full rpm. It’s designed to slip and run the hammer at less than 200 blows per minute.

Yes it will have a key way which I’m not able to machine. I do realize what you’re talking about on bearing pressure. Picture this. The flat pulley 6” long and 3” diameter is drilled 2 inches deep it slides on the motor shaft that fill 2” it rubs the tire in the middle of that 6” pulley which puts the pressure 1” beyond the end of the shaft. Keep in mind this isn’t serious pressure. It just rubs hard enough to get that tire rolling and designed to slip to control speed.
Now picture a drillpress motor with a step pulley. It sticks farther beyond the end of that shaft than that flat pulley rubs on that tire and the drillpress will have constant belt pressure on the bearings.