Homebuilt PTO SPADER..hmmm

RitchElbe · Aug 12, 2014

I am debating a new project. A home built rear pto driven spader. (see attached link) My thoughts are..2 crank shafts from a inline 6 cyclinder, use the push rods with spades brazed on. Tie the crank shafts into a limited slip rear end for power from the pto...any thoughts?
https://www.youtube.com/watch?v=Db4fWUwilXI

CNC Dan · Aug 12, 2014

RitchElbe said:
I am debating a new project. A home built rear pto driven spader. (see attached link) My thoughts are..2 crank shafts from a inline 6 cyclinder, use the push rods with spades brazed on. Tie the crank shafts into a limited slip rear end for power from the pto...any thoughts?
https://www.youtube.com/watch?v=Db4fWUwilXI

Push rods won't be strong enough.
Use the connecting rods instead.
Might not be long enough.
Differential should work if you can get a low enough ratio. Nevermind the limited slip, just weld the spider gears on a standard one.

bcp · Aug 12, 2014

I watched several of the spader videos. One showed a digging depth of 20cm, almost 8 inches. That would need a very long stroke engine crankshaft.

Bruce

RitchElbe · Aug 12, 2014

dunno why I said push rods....but I was already pondering extensions on the piston rods..

dieselcrawler · Aug 12, 2014

I've never seen anything like that... what's the advantage over a normal tiller?

RitchElbe · Aug 12, 2014

My understanding is better water absorbing qualities to the ground. No serious hard pack layer, easier to break the ground up as opposed to a tiller which of course means less wear and tear on the tractor

Baby Grand · Aug 13, 2014

It also doesn't invert the soil, leaving the soil structure largely intact.
Sounds like an interesting project!
You could use a standard auto crank and get the displacement you desire by using a lever to raise & lower the shovels.

oldnslo · Aug 13, 2014

dieselcrawler said:
I've never seen anything like that... what's the advantage over a normal tiller?

Would not be a susceptible to vine wrap either. My experience wit tillers is that vines, grass, etc. like to wrap up in them Vs being chewed up and buried.

Renze · Aug 13, 2014

Your 4100 will never lift a spader made of crankshafts that allow a foot of stroke, even a Cat C18 only has 7.2 inch of stroke.

https://www.youtube.com/watch?v=ycadZjZ1Vnw

This video explains a rotating spader with harrow roller, tech talk starting at 2:00
you can mount some readily available rigid cultivator teeth (or ripper legs) and their duckfoot spades to a shaft and drive it with a tractor final reduction, either a planetary or a portal style of an old WD45 or so... Then drive the input shaft with a chain drive for the correct speed (you cant put a big sprocket on the main rotorshaft because it will drag through the earth and the big gearbox cover will make messy work)