Tractor grapple

[ridefst]

I bought a Massey Ferguson MF1240 recently, and was using it to load logs onto a trailer with just a chain on the bucket.
It picked them up easily, but they were hard to control.

I figured that it would work a lot better if I had a hydraulic grapple on the bucket to pick up logs. It'll also be really nice when cutting them up for firewood, as I should be able to just hold a log a few feet off the ground and cut it into 18" pieces pretty easily.

I started with a photo of the bucket and a tape measure, so I could scale it properly in SketchUp.


I played around with different shapes, and cylinder lengths - ended up with this:
I'm only building one grapple, but drew an extra one to picture it both open and closed.


I'm fortunate to have a friend working with a large laser, so I sent the files over to him to get cut out of 1/2" steel.

I'm not very good at stopping work to take pictures...
But here's where I got to after one evening of assembly




Here the cylinder mounts are finalized. Just took the plugs out of the cylinder and stroked it by hand to figure out exactly where they needed mounted. I couldn't move the cylinder at first, so used an air blow gun to get it started, but after that it wasn't too hard to push/pull by hand.




Waiting on hoses now, it'll be run by a solonoid diverter valve off the curl function.
Hoping to get it running by the weekend.

The welds are decidedly not awesome, I'm much better with MIG than stick, but my MIG is far too weak for 1/2" steel, so I had to use the stick for once. I'm sure they'll be strong enough, but they are nothing special to look at, that's for sure!

 

[Citydude]

Nice work! Looks to be up for the task.

 

[MinnesotaEric]

Excellent. Looks like you hooked up a to a computer controlled plasma cutter.

Well done.

 

[ridefst]

Excellent. Looks like you hooked up a to a computer controlled plasma cutter.

Well done.

Nope, this is a step above plasma. I believe it's a 2,500 watt Amana laser.
The 1' and 3/4" pin holes required about 30 seconds of grinding with a dremel to clean up one small bump at the exit, and then the pins slipped right in with almost zero slop.
The cut quality is just amazing.

 

[tvman]

That looks good! I built one similar but the full width of the bucket. I might suggest though that you weld on some stops at the grapple hinges to keep the lid from opening past center.

Mine worked great for doing just what you are doing. I also got some teeth to bolt onto the bucket lip, some thing are hard to pick up without it.

 

[ridefst]

That looks good! I built one similar but the full width of the bucket. I might suggest though that you weld on some stops at the grapple hinges to keep the lid from opening past center.

Mine worked great for doing just what you are doing. I also got some teeth to bolt onto the bucket lip, some thing are hard to pick up without it.

I think I'll be ok on opening past center - the cylinder bottoms out before it can go over center. Good to keep in mind though, we'll see how it actually works out with fluid.
I was wondering about teeth on the cutting edge, nothing planned at the moment, but I could definitely see adding those later, depends how much trouble I have grabbing logs off the ground.

 

[Mysfyt]

Very nice design! What cad program did you draw it on?

 

[nybirdman]

Nice.I have the factory make "thumb".A tooth-bar will make it a lot easier to pick logs.

 

[petegoud]

Nice job, you may want to build up the flat plate holding all the top brackets. I've experienced some bending there using a similar flat plate. A lot of pressure on the top of the bucket, especially when carrying a large heavy log, and bouncing up and down in the woods.

 

[ridefst]

Very nice design! What cad program did you draw it on?

www.sketchup.com
Very easy to use, and they have a free version to boot!