Rotary motion to reversible linear motion

[olf20]

I'm not totally happy with the way motion is transferred from the steel pressure plate to the final drive shaft via the rubber o-ring, so am making up a couple of compression spring holders to hold compression springs against the final driveshaft bearings to hold a more constant pressure between the rubber o-ring and the steel pressure plate.----Brian

All the snow blowers that use this type of drive use a lever and operator to apply
the pressure to the two. But they do work great for a long time, not to mention you
get reverse as a bonus.
olf20 / Bob

 

[Brian Rupnow]

What did I do today?--Well, not that much really. Since I am now going to put roller bearings on the shaft that meshes with the rack to drive the carriage back and forth, I had to make a new gear which gets locked to the new hardened shaft. (The old gear and shaft were machined from one piece of mild steel.) I like this gear better--the outside diameter of the first gear was not perfectly concentric to the bore, so it had a hard spot in it when the rack travelled full length. I haven't decided yet whether to make the new shaft from a piece of 1045 steel and leave it unhardened (but harder than mild steel) or to make the new shaft from 01 steel and harden the areas where the bearings ride on. Problem is, there's a keyway milled down one side of the shaft, and I don't know if the shaft will remain straight after hardening or if it will "banana" on me because of the keyway.