Hinge for folding bale tines

[madtowneast]

I am trying to design some bale forks with folding bale tines. I got as far as the general structure.

I am somewhat stuck on the details. The square tube are sized according to other bale forks I checked out (3x4x1/4, 2x4x1/8). The plate used is 3/4" right now, which may be overkill, but they are meant to handle up to 3000 pounds.

The big thing I am stuck on is how to design the hinges. Looking at other examples of bale tines with moving tine bar, the pins they use vary between 1/2 - 1-1/2". I was thinking about using some off the shelf 25 mm excavator bucket pins, but they are usually housed with bearings, etc. which seems overkill to other examples I have found: Example 1, Example 2, Example 3, Example 4

Anybody have inside into how to design the hings?

 

[zzvyb6]

1) You haven't defined the bale size or weights expected.
2) Why folding ? Can't you just do a QA tine rack and pick up or drop off as needed ?
3) If you insist on fold down tines, use a locked down type hinge that you release with a pin? When in bale holding position let the spikes be sitting on the stops.
4) Whats the weight carrying capacity of your loader or 3 point hitch ? This looks very heavy for just a round or large square bale.
5) Were you thinking hydraulic deployment ? Individual spikes aren't that heavy.
6) How many bales do you want to carry at 1 time ?

 

[madtowneast]

1) You haven't defined the bale size or weights expected.

Up to 3000 pounds, with 2 large square bales of alfalfa.

2) Why folding ? Can't you just do a QA tine rack and pick up or drop off as needed ?

When stacking over 3 high in my barn, pulling out the tines gets dicey. They tend to "stick" to the bales and want to pull the entire stack down. With the hinge you can "push off" without needing hydraulics.

3) If you insist on fold down tines, use a locked down type hinge that you release with a pin? When in bale holding position let the spikes be sitting on the stops.

I designed stops into the back, so the tines can only tilt towards the upper portion. And some 1/2 holes for a pin if needed

4) Whats the weight carrying capacity of your loader or 3 point hitch ? This looks very heavy for just a round or large square bale.

2x large square bales of alfalfa, so about 1200-1300# each.

5) Were you thinking hydraulic deployment ? Individual spikes aren't that heavy.

No

6) How many bales do you want to carry at 1 time ?

2-3 depending the size and type.

 

[zzvyb6]

What do you think of some sort of 'push-off feet' ? My stack wagons have various versions of 2 plates that extract the machinery. Could be dangerous, though: max height and you on the brakes.