Bearing advice request

[Cadillac]

To keep the arm from moving to freely just adjust the bearing preload to be stiff. Or make some holes with a corresponding pin on the hub so when stowed one can pin it to lock in position so it can’t spin.
I used a electric winch on mine saves from all the cranking. Hardest part on a vehicle would be finding a solid place to mount the apparatus. Which I would think a 12” square plate 1/4to1/2 thick as the base with large U bolts strattling the frame would work.
Looking at your post mounting it to the receiver is good but then you will be swinging the load over the bed rails. Which your load will have to be high. Mounting on the side will allow the load to swing center in the bed. Just a thought.

 

[Ulma Doctor]

Hi PH Paul,
i'd consider delrin as a bearing.
tapered roller bearings would be a great feature, but for what is being asked i think roller bearings would be superfluous.
1/4" to 1/2" inch of delrin would work for a lifetime, add an inch of delrin if you are at all suspect to weight distortion
delrin is self lubricating.
in this instance grease or oil could be used to reduce friction, but really, i'd try it dry first.

i'd like to see the finished product, i have considered masking one myself

 

[Alexander McGilton]

I would not be using a wheel bearing from a trailer. The one listed above is rated to 1750lb of radial load, nothing said for axial or especially moment. Say the two bearings are 3'' apart or 1/4 foot. that 2000ft-lb is now 8000lb radial per bearing.

 

[PHPaul]

Thanks for all the input.

My plan (as much of one as there is) is for the base to plug into the hitch receiver on the truck, with a drop-leg side-crank trailer jack to transfer the load to the ground.



Looking end-on at the back of the truck, base (in black) plugs into the hitch receiver, jack (in red) can be attached directly to the base or moved to the end of the outrigger (in blue) if swinging a particularly heavy load. Outrigger could be attached to left or right side as needed.

Please feel free to critique my brainstorming, especially if there are load bearing or safety concerns.

 

[hman]

I've had pretty good luck on a low duty cycle application with what amounts to a disk (washer) cut out of a bleach bottle. The plastic is some kind of polyethylene or polypropylene and will reduce friction nicely. It's pretty robust, cheap to replace, and not as messy (and attractive to grit) as grease - especially if you frequently disassemble the hoist.

What might turn out to be even more important than the thrust bearing/washer is (as Alexander McGilton pointed out, the side load on the rotating mast and fixed base. If nothing else, make the rotating base out of something heavy walled, and extend the mast into the base as far as possible.

 

[pontiac428]

Here are some pics of a system that is becoming popular for fall arrest systems. Also jib cranes, and other stuff to be stabilized off of a receiver hitch:

 

[hman]

WOW!!! Love 'em - especially the one that swivels to the side! I've been toying with the idea of adding a hoist to my pickumup truck, but never yet found a design I liked. Gotta start thinking about how to implement one of these. Thanks for the pix.