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

"Clare Snyder" wrote in message
...

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.

On Sun, 18 Apr 2021 00:14:48 -0400, Clare Snyder
wrote:

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

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

On Sun, 18 Apr 2021 16:07:57 -0400, Joe Gwinn
wrote:

On Sun, 18 Apr 2021 00:14:48 -0400, Clare Snyder
wrote:

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

6061 makes for a terrible bearing.

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

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

Joe Gwinn
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.

"Clare Snyder" wrote in message
news
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.