Why do PTO shafts need to be cut equally?

[newbury]

As long as the resulting combined shaft does not either bind or separate in use why is there such emphasis on them being cut exactly equally?

 

[Bill Guenthner]

Equal length halves gives the largest range from shortest to longest operating length.

 

[JC-jetro]

I think you would split the difference equally to both ends of cut shaft. let's say implement is higher or lower due to terrain or tractor pto shaft elevation higher or lower due to the same. Remember is the shaft is not cut short enough and you have a heavy implment like a tiller and if you lower and hit a bump then then energy (potential and Kinetic) would be against the tractor rear and PTO final shaft. It could potentially bust the rear housing, damage the pto and seal there. You also need good inner and outer cut shaft overlap for good torque transfer.

 

[RalphVa]

They slide together and have to match up. One side too long, and that is all it will slide to: the length of the long part.

 

[jaxs]

If you had a 72" shaft when collapsed and cut 24" off one to get the needed 48",there would be only 12" "overlapping". Had you taken 12" from both there would be 24" overlapping which spreads load over twice the sq inches of engagement and an extra 12" up/down shorter/longer flexibility.

 

[Sawyer Rob]

As long as they have enough overlap and don't bottom out, it doesn't matter one bit.

I bet some of mine aren't and I've never had one problem.

SR

 

[oosik]

I measured thrice - cut once. Half off each shaft. EXACTLY as the Op Manual indicated. Never had one problem.

 

[5030]

...so the rotational forces are equally applied to both sections. Simple really.

 

[wirlybird]

As long as the resulting combined shaft does not either bind or separate in use why is there such emphasis on them being cut exactly equally?

You wouldn't necessarily need to cut each tube "exactly" the same length but remember that the overall shaft will only collapse or go as short as the longer tube section allows.
And as mentioned equal length tubes will give the largest range of short to long while maintaining a safe amount of overlap in the tubes.

 

[ericm979]

For the last one I shortened, I cut the plastic shields a 1/2" shorter than the shafts. That makes it easier to slide the shafts together as you only have to align the shafts or the shields but not both at once.