Quote:
Originally Posted by jspatz1
Here are some aluminum hubs that might be suitable http://www.andymark.biz/hubs.html AndyMark has many hubs, bearings, shafts, collars, and bearing holders that might suit your needs. FRC robot builders rely heavily on AndyMark for parts.
For a cheap shaft coupling, with the low torque you are dealing with, a short piece of stiff rubber tubing and hose clamps might be suitable. The flexibility will allow for a some misalignment in your assembly.
Be careful of "sealed" vs. "shielded" ball bearings. "Sealed" bearings have some friction from the seal and are not free-wheeling. "Shielded" will keep out most dirt and debris, but are low friction. I assume with a wind application you are looking for as low friction as possible.
|
I was going to point him at the andymark hubs as well.
He can get ground aluminum bar that will fit in them from mcmaster. I would used flanged roller bearings to support the longitudinal loads, with a single thrust bearing at the top to ride on. Picture included.
For the speed reducer I would consider gates belting and pulleys, or 25 chain and andymark sprockets.
In addition, don't we get some dandy pillow-block jounted bearings that are self-aligning from igus that would work perfectly for this that he could bolt to a 2x4? I believe we used ours this year in a prototype shooter design, but if someone has them laying around that might be an easy way to do this too.
Thrust bearing:
http://www.mcmaster.com/#thrust-bearings/=94uhvf
Flanged Bearing:
http://www.mcmaster.com/#ball-and-ro...arings/=94ujic
1/2" aluminum precision ground shaft:
http://www.mcmaster.com/#aluminum/=94uk75
Use andymark hubs. Attach by drilling a hole through the hub and the shaft and pinning (can be done with a drill press so you dont' have to do any broaching for hex shaft or milling for keyways). Andymark has 25 chain sprockets that will bolt up to the hub directly for power transfer.
Use a hole saw to drill holes for the linear bearings then press them in. Put everything on the shaft before screwing in the short 2x4 portions to make sure it's lined up and freely rotating.