Take 2 - pto drivelines for an L3901 to a drum mower

[icehorse]

This is a new approach to the related thread:

The basic setup is: tractor -> driveline #1 -> mower's gearbox -> driveline #2 -> drums.

Driveline #1 is too short for a slip clutch. I cannot find a driveline with 6-splines on BOTH ends, AND a shear bolt.

IF anyone knows of such a driveline that would solve the problem.

The new idea is to use a slipclutch on driveline #2. ?! Pros and cons?

 

[TheOldHokie]

This is a new approach to the related thread:

The basic setup is: tractor -> driveline #1 -> mower's gearbox -> driveline #2 -> drums.

Driveline #1 is too short for a slip clutch. I cannot find a driveline with 6-splines on BOTH ends, AND a shear bolt.

IF anyone knows of such a driveline that would solve the problem.

The new idea is to use a slipclutch on driveline #2. ?! Pros and cons?

Obviously no shear pin on a splined yoke. The manufacturer does not seem to think anything is needed. Why do you?

Dan

 

[icehorse]

Obviously no shear pin on a splined yoke. The manufacturer does not seem to think anything is needed. Why do you?

Dan

I bought what turned out to be a crappy drum mower. That's on me, I'm making the best of it. The mower came with an overrun clutch which I do not need and which will not protect my tractor.

Let me ask you about your first comment - I have many 6-spline drivelines and one of them has a shear bolt on one of the yokes. So I'm not sure I understand your first sentence, can you clarify that?

thanks!

 

[TheOldHokie]

I bought what turned out to be a crappy drum mower. That's on me, I'm making the best of it. The mower came with an overrun clutch which I do not need and which will not protect my tractor.

Let me ask you about your first comment - I have many 6-spline drivelines and one of them has a shear bolt on one of the yokes. So I'm not sure I understand your first sentence, can you clarify that?

thanks!

The yoke with the shear pin is not splined. If it is thats not a shear pin. Think about it.

 

[icehorse]

The yoke with the shear pin is not splined. If it is thats not a shear pin. Think about it.

I think our lingo is mismatched here And mine is probably wrong. The yokes on both ends have to accept the male, 6-splined stubs. I'm looking for a pto driveline assembly with the yoke ends I just described AND with one of the yokes also having a shear bolt.

When the yoke slides over the stub there is about 2.5 inches of overlap. The last 2.25 inches of the yoke will get detached from the rest of the yoke if the bolt shears. That 1/4 of overlap is okay because the ends of the stubs taper away (smaller), from the full 1 3/8 diameter of the stub. So when the bolt shears the stub's splines are only engaged with the end of the yoke that sheared off.

I think?

 

[TheOldHokie]

I think our lingo is mismatched here And mine is probably wrong. The yokes on both ends have to accept the male, 6-splined stubs. I'm looking for a pto driveline assembly with the yoke ends I just described AND with one of the yokes also having a shear bolt.

When the yoke slides over the stub there is about 2.5 inches of overlap. The last 2.25 inches of the yoke will get detached from the rest of the yoke if the bolt shears. That 1/4 of overlap is okay because the ends of the stubs taper away (smaller), from the full 1 3/8 diameter of the stub. So when the bolt shears the stub's splines are only engaged with the end of the yoke that sheared off.

I think?

Your analysis is way off. The splines carry 100% of the torque. The pin/bolt is not invshear and just keeps the yoke from slipping off the male splines.

Dan

 

[icehorse]

Your analysis is way off. The splines carry 100% of the torque. The pin/bolt is not invshear and just keeps the yoke from slipping off the male splines.

Dan

Yeah, I still think we're having a lingo mismatch. I'm not talking about the push-pin that some drivelines use to make sure the shaft doesn't slip off the stub. I'm talking about a separate shear bolt that attaches the last 2 inches of the yoke to the rest of the yoke and the whole pto driveline. this bolt usually runs parallel to the shaft itself. So when the bolt shears, the yoke comes apart. The last two inches are still overlapping the stub. But the rest of the yoke and the whole driveline is no longer attached.

But this is making me think that the 2", short end of the yoke that gets detached ought to be the tractor end - so only the short piece is still spinning.

 

[TheOldHokie]

Yeah, I still think we're having a lingo mismatch. I'm not talking about the push-pin that some drivelines use to make sure the shaft doesn't slip off the stub. I'm talking about a separate shear bolt that attaches the last 2 inches of the yoke to the rest of the yoke and the whole pto driveline. this bolt usually runs parallel to the shaft itself. So when the bolt shears, the yoke comes apart. The last two inches are still overlapping the stub. But the rest of the yoke and the whole driveline is no longer attached.

But this is making me think that the 2", short end of the yoke that gets detached ought to be the tractor end - so only the short piece is still spinning.

Q: Why do you have splines.
A: To carry high torque loads and prevent slipping

Q: Why do you have a shear pin
A: To carry and limit the shick loads

Q: How can a shear pin limit torque and prevent shock loads on a spluned hub?

I have no idea what you are describing or how it would work

Dan

 

[icehorse]

Q: Why do you have splines.
A: To carry high torque loads and prevent slipping

Q: Why do you have a shear pin
A: To carry and limit the shick loads

Q: How can a shear pin limit torque and prevent shock loads on a spluned hub?

I have no idea what you are describing or how it would work

Dan

 

[TheOldHokie]

View attachment 175711 View attachment 175711

Thsts hew to me and seemingly solves your concerns.

 

[icehorse]

Thsts hew to me and seemingly solves your concerns.

Almost! What I want to find is the whole assembly not just 1/2 a yoke.

 

[JasonW]

Woodland mills sells a PTO shaft like you are describing. Splines on both ends with one having a shear bolt.

I had to buy one for my wallenstein chipper.
Post some pictures of your setup. Did the mower you bought not come with PTO shafts?

 

[Russell King]

Also look at tiller drive shafts. Some of them have a yoke like that.

But you should be able to find both halves of the yoke and replace it on your existing shaft.

 

[PoTreeBoy]

Almost! What I want to find is the whole assembly not just 1/2 a yoke.

Google 'pto shaft with shear pin or clutch' and you'll find your choice. You'll probably have to cut it to length.

Back to your design choice - since the purpose of the pin/clutch is to prevent or minimize damage to the driveline due to overload reflected from the implement, it makes since to install it as close to the implement as possible.

 

[BAP]

View attachment 175711 View attachment 175711

That design has been around for many many decades and works very well. It’s used in a lot of haying equipment including pull type forage choppers.

 

[BAP]

Check out this website for Agrisupply. They have a lot of PTO driveline parts including what you are looking for. You have to scroll through the list to find them.

PTO Shaft, PTO Parts, PTO Adapter, PTO Power Take Off, Eurocardan

Agri Supply stocks an amazing selection of Eurocardan PTO shaft parts and accessories, including clutches, tubes, and yokes for your tractor and implements.

www.agrisupply.com

 

[NCL4701]

My Woodland Mills WC-68 chipper has a PTO shaft like what you’re looking for. I would call them and ask about getting one if you don’t find one easily at Agri-Supply or similar retailer.

I’ve only called them once, but the folks in their parts department spoke English fluently, weren’t talking off a script, and appeared to have the ability to think and respond like normal people (I know that’s hard to believe, but it’s true).

 

[icehorse]

Google 'pto shaft with shear pin or clutch' and you'll find your choice. You'll probably have to cut it to length.

Back to your design choice - since the purpose of the pin/clutch is to prevent or minimize damage to the driveline due to overload reflected from the implement, it makes since to install it as close to the implement as possible.

A few days back I thought the shaft with a shear bolt would be easy to find.

But thanks to the folks who mentioned woodlandmills - they've got what i want!