Small bearing or low-friction "pin" to assemble t-slot frame

[jamesson]

Howdy folks

I have to say up-front, that I am not an ME by trade. My background is in EE. So, I apologize in advance if I accidentally make my question confusing.

I need to join a couple of these

http://www.minitecframing.com/Produ...talog_Pages/20.1074_19X11_Profile_Square.html

with a bearing that will allow rotation along one axis. I need to provide a bearing that will go in the outer slot (red rectangle) and provide rotation around the central axis (blue line)

Could be a bearing, could be a simple "pin" of Teflon or some other low-friction material. I would like the option of either fixing linear motion in the slot or letting it move freely,

but if only one of those options is possible, I will go with whatever is cheapest. As you can see from the site, they have their own nuts and bolts for fixed joints, so if my only (reasonably priced) option is to have something sitting outside the slot, so be it.

The primary design parameter is price, followed closely by durability. I expect it to be used 5-10 times a day for a period of some years, and experience lateral stress (perpendicular to axis of rotation) of approximately 20-40 lbs. Also, if it's any more than $1/piece, I may have to rethink the project.

In general, I am extremely curious about the process you folks use to find stuff like this. I'm assuming people don't just send drawings to McMaster-Carr?

Many thanks in advance for any help

Joe

 

[Tom.G]

Nothing specific but a Google search for Swivel Key Ring returns many ideas that may lead to something.

I also tried Swivel Lifting Rings but they are rated in tons of lift ability and prices are the 3-digit variety.

Fishermen use something called a Barrel Bearing Swivel that may be modifiable, 60lb test and $0.50 each. see:
https://www.amazon.com/dp/B00H991N3S/?tag=pfamazon01-20

So there are a few leads, hope it helps.

Tom

 

[tygerdawg]

For that kind of duty cycle perhaps you would consider a simple dowel or pin inserted into a bushing. Add a little grease.

 

[jamesson]

For that kind of duty cycle perhaps you would consider a simple dowel or pin inserted into a bushing. Add a little grease.

Where would I get a pin like that? Or grease?

 

[CWatters]

Google suggests that the head of an M5 cheese head bolt has a diameter of 8.5mm which would just about fit the 8.6mm slot? Perhaps you could use one of the M5 square nuts they sell into the other side. Adjust the screw through a hole and hit the threads of the square nut with locktite or similar?

 

[jamesson]

Google suggests that the head of an M5 cheese head bolt has a diameter of 8.5mm which would just about fit the 8.6mm slot? Perhaps you could use one of the M5 square nuts they sell into the other side. Adjust the screw through a hole and hit the threads of the square nut with locktite or similar?

Absolutely worth a shot as a proof of concept. Any suggestions for lubrication?

 

[CWatters]

Wheel bearing grease?