|Forum topic by William Shelley||posted 06-21-2014 08:45 AM||819 views||0 times favorited||3 replies|
06-21-2014 08:45 AM
Continuing work on the shopmade bandsaw project, part “I lost count” of “to infinity, and beyond!”...
I’ve gone through many designs in my head for making wheels, most involving a piece of plywood or MDF with a hole in the middle. This plan, while simple on the surface, starts to become more complicated as I have a drill press with only a 16” swing, and the wheels I need to make will be 20” in diameter. The shafting material I’m using is 1-1/4” alloy 1045 cold rolled, turned, ground, and polished steel.
I tried an approach using 3/4 MDF cut into six strips of about 7” wide, boring the shaft holes in the center, of the ‘middle’ pieces, and then gluing everything up with layer 1 being perpendicular to layer 2. The glue-up and construction worked great, it was very flat and seemed sturdy.
What fell apart with this idea is that I had no feasible way to fasten the wheel to the shaft. I know that in some designs, a bandsaw wheel will have bearings in the bore and the shaft will be fixed to the machine frame. I could do this on the top wheel, but the bottom wheel needs to be fixed to the shaft since it’s the driving wheel. My current best guess solution for this problem is JB Weld. It’s strong, will bond to metal, and has high shear strength.
But then today I came up with a different idea. What if I were to build a pair of segmented wheels from hardwood (Hickory spokes and maple rim), that were each made as two halves and bolted together to ‘clamp’ onto the shaft? I could even take it a step further and drill a hole for a 1/4” bolt or threaded rod to pass all the way through the shaft, applying clamping pressure and acting as a key to prevent slippage while still allowing disassembly if necessary. I am slightly concerned about weakening the shaft by drilling a hole all the way through it. I don’t have a bottoming tap but I could probably tap threads partially into the steel, or perhaps even just use a ‘pin’ inserted 1/4 or so into a hole to act as a key.
Here’s a rough sketch of what I have in mind. What I’m looking for from the LJ community is some tips or advice on pitfalls I might run into, so that I’m armed with the best information available before I start cutting anything.
Thanks a lot for reading.
-- Woodworking from an engineer's perspective