U-Joint operating angle?

Guys I am building an intermediate drive shaft for a project that runs between 2 fixed gearboxes. Theoretically the output of gearbox 1 and input of 2 should be perfectly inline... but my world isn't perfect so I'm sure there is some slight misalignment so I want something to accommodate for that. I've been told that a U-joint operating at zero or nearly zero angle will fail in short order, because the needles won't be spinning properly in the caps.

Any truth to this or will I be just fine with a Ujoint at hopefully zero angle?

Use a 'lovejoy' coupler instead.

They need to be at a slight angle https://www.youtube.com/watch?v=Idk3BVDVHq4

https://www.youtube.com/watch?v=Idk3BVDVHq4

True about the angle, but what load are you runnning? Low load will last a long time. No angle causes
brinnelling. Little needles make grooves on the loaded side of the center cross and possibly in the cap.

I would agree, use a lovejoy coupling if planning to be aligned.

Thought about a lovejoy but have never seen one hold up in a 100hp+ application.

Maybe I've just never seen one sized appropriately.

(quoted from post at 08:25:09 07/27/18) Thought about a lovejoy but have never seen one hold up in a 100hp+ application.

Click to expand...

They have a dual chain coupler for high horsepower applications. Each end of the shaft a sprocket which takes a big chain (same amount of teeth on each sprocket) then a double row roller chain with a master link to put the chain together. Then it has a plastic cover for the chain so the coupler can hold grease. Google surpluscenter they have the double roller chain couplers, and good local bearing house should have them also. But for chain couplers they have to aligned, and they are not made operate or move at an angle. We used them on 100hp electric motors running hydraulic pumps.

Isn't that (Two sprockets with a double chain) the type of deal used to connect the engine to transmission in Oliver tractors? Somewhere around the late sixties, early seventies?

I thought that I remembered a coupling like this in a 1755 Oliver.

Pair of sprockets with a roller chain wrapped around them. Very common connector for your use.

Lovejoy connector.

As you say you likely won't get it perfectly aligned, so a U joint probably gets enough rotation to work out?

Paul

Dual chain coupler should hold up.

A u-joint is not appropriate for the application you describe.

Check these guys out:

http://www.magnaloy.com

https://www.rexnord.com/products-services/process-motion-control/couplings/elastomeric-couplings/omega-elastomeric-couplings

https://www.rexnord.com/products-services/process-motion-control/couplings/grid-couplings

http://www.lovejoy-inc.com

Just to name a few.......

(quoted from post at 06:44:28 07/27/18) Guys I am building an intermediate drive shaft for a project that runs between 2 fixed gearboxes. Theoretically the output of gearbox 1 and input of 2 should be perfectly inline... but my world isn't perfect so I'm sure there is some slight misalignment so I want something to accommodate for that. I've been told that a U-joint operating at zero or nearly zero angle will fail in short order, because the needles won't be spinning properly in the caps.

Any truth to this or will I be just fine with a Ujoint at hopefully zero angle?

Click to expand...

I?ve seen lots of farm equipment with u joints
running at zero angle . New Holland swather
headers for one and Hesston swather headers .
Seen one on face book one time where the u joint
was about 4 feet across

The reason for CV (constant velocity) joints is to eliminate any problems caused by different lengths of shafts in a drive train. What I read on the
subject mentions that at different lengths there is some slop (overrun-under run shaft differences due to odd lengths) in the shafts which cause the
vibrations. Running zero angle I wouldn't bother.

Case in point. I bought an old Starcraft I/O which I fully restored. The drive shaft from the engine to the outdrive had a CV joint. Purpose was to keep
the outdrive from vibrating as the turning angle increased. I was strapped for cash at the time and didn't rebuild the CV joint with OEM parts. Sure-nuf,
at zero turning angle zero vibrations. As I turned to either side, as the angle increased the vibration intensity increased.

I had a JD 1209 swather and 530 baler, neither having CV joints. A drawbar extension of about 14" was used to achieve equal lengths and eliminate
vibrations. My current baler is a JD 375 which has a CV joint on the tractor end...............and is a !@#% for one person to couple to the tractor. It's
heavy and the tractor's shaft is locked....have to take the pressure off the belts and rotate the input shaft of the baler while putting pressure on the
coupling to get the splines lined up so it will connect, all while supporting the weight of the shaft and CV joint. Another one of Mother Deere's neat
inventions.

Forgot all about a chain coupler. They can take the power and are good for 1 to 2 degrees of misalignment which hopefully I will have less than that.

Did you actually measure?

.5 of a degree would be hard to discern with the naked eye.

If there isn't at least that much built into the design the u-joint will fail prematurely.

Fact of life........

(quoted from post at 00:14:36 07/28/18) I?ve seen lots of farm equipment with u joints
running at zero angle . New Holland swather
headers for one and Hesston swather headers .
Seen one on face book one time where the u joint
was about 4 feet across

Click to expand...

It is true-the needles will wear indentations on the inside of the cups.That wear is called brinneling. There is special tool that looks like a protractor,with a magnetic base,and pointer that points at 0 at perfect ,level.You set it on the yoke,and then on the shaft and then subtract the difference.That will be your degrees of angle. I believe 2-3* is the minimum.Mark.