Wood wheels for belt grinder

[BayardStrachan]

Is making wood wheels for a 2x48 belt grinder possible, or even safe? I have everything but the wheels and I haven't found any wheels in nz for a halfway decent price. I have access to a wood lathe.

Also, do all of the wheels need to be crowned, or Is it either the drive wheel or the tension wheel or both?

Thanks, Bayard 

[George N. M.]

I would worry about 2 problems.  1) Is wood, even a hardwood, strong enough to resist the centripidal forces at the speeds a grinder opertes at? 2) How fast would wood wear at the mounting holes?  Is it possible? Yes.  Is it practical and safe?  I'm not sure.  If you were dealing with lower speeds in a hand driven piece of machinery I'd be more positive but high speeds makes me leery.  Perhaps an extensive safety cage around the wheels would be possible.

Folk with more wood working and lrge grinder experience may have a different opinion.

"By hammer and hand all arts do stand."

[Stash]

To respond to George's questions, 1 I would turn the wheel from glued up quality plywood, and 2I would press  a steel bushing into the center hole. Will the wheel be spinning on the shaft? I would press in a bearing.

Steve

[George N. M.]

Stash, good responses to my concerns.  I still wonder about durability, e.g. the pressed in bearing becoming loose in the wooden wheel.  Maybe he could make a stack of them and trade them out fairly often.

GNM

[BayardStrachan]

What if I pressed a steel bushing into the wood, and into the bushing, a bearing, I feel like that might work? 

Main concern is how to anchor the drive wheel to the motor shaft, any ideas? 

[gewoon ik]

I have seen belt grinder with wooden wheels. In a woodworking shop.

It did not run thrue. But the speed was kept lowish.

[Frosty]

Dad made metal spinning dies from glued maple blocks, alternating the grain direction and we ran some pretty high rpm depending on the part and they took considerable forces against them from the work being done. It was a scissor tool shop so forces against the die were significant. 

I'd look for or rip/plane thinner than 1" to laminate and no bushing AND bearing you can buy press in bearings with a key or glue it in. The shaft on your motor or jack shaft should have a keyway or flat to lock it with a set screw in a hole deep enough to plug with wood and smooth to match the wheel.

Frosty The Lucky.

[BayardStrachan]

Thanks everyone for the replies, I may have to parn this project though, I thought my motor could turn faster than it does. 

[Buzzkill]

I used a wood drive wheel for a while on the 2x72 grinder I built.  This may not be ideal, but I used a couple pieces of (oak I think) 2x4 glued with the grain 90 degrees from each other.   I marked and drilled a center hole just a hair undersized so I had to tap it into place on the shaft.  The shaft was keyed, and wood is softer than steel so I tapped a key into place to hold it securely.   Then I clamped the motor to a workbench and used a piece of RR track as a work rest for lathe tools to get the wheel perfectly round.  I used the wheel for more than a year with no problems and now use it on the power hammer I built. You should crown either the drive wheel or the tracking wheel if I recall correctly, but not both.  If I were to do it again I would drill pilot holes and add 2 or 3 wood screws to help hold the pieces together for some additional peace of mind.

What's the rpm of your motor?   The first version of my belt grinder used a 1 hp motor with 1750 rpm.  I used 2 step pulleys opposite of each other to change the belt speed.  That's not as good as a variable speed 3 phase motor with a VFD, but it worked ok for me in all but the fastest setup.  I could stall the motor fairly easily in that arrangement.

 

[JHCC]

If you add wood screws, make sure that they are spaced evenly around the wheel and the same distance from the center, to minimize how much they interfere with the wheel's balance.