aluminm bearing for pivot?

I am making a swing-away bike carrier to fit in trailer hitch reciever. With everything shut down I need to use what I have on hand. Can I use 6063 aluminm (rigid aluminum conduit) as a pivot bearing? I plan on pressing it into a steel sleave. Loasding will be under 200 lbs at 30 inches - bearing length 1 1/4 inches - shaft 5/8 to 3/4 inch. The arms are made of 3/16" wall 1 1/4 inch square tube. and I don't really want to just bear the load steel to steel on the 3/16 inch wall thickness or a steel tube on the pin. Not sure what my pin material will be yet untill I get through my "ends" box on Monday would be good if I could find some chrome shaft like a shock absorber/strut shaft or hydraulic cyl rod

Reply to
Clare Snyder
Loading thread data ...

I am making a swing-away bike carrier to fit in trailer hitch reciever. With everything shut down I need to use what I have on hand. Can I use 6063 aluminm (rigid aluminum conduit) as a pivot bearing? I plan on pressing it into a steel sleave. Loasding will be under 200 lbs at 30 inches - bearing length 1 1/4 inches - shaft 5/8 to 3/4 inch. The arms are made of 3/16" wall 1 1/4 inch square tube. and I don't really want to just bear the load steel to steel on the 3/16 inch wall thickness or a steel tube on the pin. Not sure what my pin material will be yet untill I get through my "ends" box on Monday would be good if I could find some chrome shaft like a shock absorber/strut shaft or hydraulic cyl rod

-------------------------------

Steel on steel is/was common on lawn and garden equipment, and it lasts a long time on joints that don't often move, and some that do.

I bought a 20-year-old Toro snowblower whose auger and ground drive control handles were sheet metal U-shaped pressings running on steel pivots, the bearings being just punched holes. The more stressed auger drive handle had worn egg-shaped on the control rod side but the less stressed ground drive handle was still fine.

I located the handle by the unworn side of the hole under the mill spindle and bored for a bronze bushing and now it works like new. The older all-steel ones are easy to fix.

Reply to
Jim Wilkins

6061 makes for a terrible bearing.

Use delrin or the like. One can also buy pre made delrin bearings for small dollars from McMaster.

Joe Gwinn

Reply to
Joe Gwinn

Remember the speed is about 4 RPM and only 90 degrees of motion.

I'm using brass. I found a couple brass fittings that will fit on a

15mm or 5/8" shaft whichever I can find. I'll see what our local Metals Supermarket has available. We are under lockdown up here and getting ANYTHING is a long drawn out affair. The Myford Super 7 can help me make what I need out of what I have or can scrounge. I have HMWPe that I could make the bushings out of too but I think it would be more likely to deform under the load when opened.
Reply to
Clare Snyder

I'm using brass. I found a couple brass fittings that will fit on a

15mm or 5/8" shaft whichever I can find. I'll see what our local Metals Supermarket has available. We are under lockdown up here and getting ANYTHING is a long drawn out affair. The Myford Super 7 can help me make what I need out of what I have or can scrounge. I have HMWPe that I could make the bushings out of too but I think it would be more likely to deform under the load when opened.

----------------------------

The nominal ID of 1/2" pipe is 0.622".

I made the pivots for the hydraulic bucket loader for my garden tractor from

3/8" brass pipe nipples (ID 0.493") and 0.500" O1 drill rod. When I disassembled it several years later one pin was measurably but not visibly bent from hitting a stone step under the snow but the well-greased brass bearings were like new.

Cut off ends of brass nipples are valuable as mandrels with pipe threads that run true to the chucked OD.

TIG welding retaining plates onto one end of the drill rod created a brittle zone beside the weld that I had to anneal. Replacements for pins that broke were cross-drilled for retainers instead. The problem is that the pivot pin has to be rigidly attached to the thinner outer members of the fork joint so only the larger steel/brass surface rotates.

Parts diagrams for front end loaders show how manufacturers have designed the pivot components. Bucket loaders are cut and assembled from stock shapes of plate and rectangular tubing in ways applicable to hobby construction. The hardest problem I faced was keeping widely separated bearing bores sufficiently parallel.

I'd consider oilite sleeves for the bicycle carrier, because plastic can be difficult to machine to size. The design bearing pressure in my loader exceeded oilite's rating.

I stopped using the loader and bought snow blowers because I had repaved the driveway. The bucket chewed up soil and the edges of asphalt when snow fell on mushy thawed ground that didn't support the skid plates.

Reply to
Jim Wilkins

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.