Root Rake/Grapple For Kubota B2910

[rswyan]

More parts accumulating after being cut:

 

[rswyan]

These four 1/4" x 6" plates will form the towers/masts into which the upper jaw will mount. They were tacked together in pairs for machining/drilling:

In hindsight it would have been better had I tacked all four of them together - which would have left no chance of any variation in hole placement, even if a bit unwieldy ...

As it turned out, one of the series of holes was slightly off between the two sets ... no biggie: grind a little out and fill it with weld ...

 

[rswyan]

Drilling the holes. Lennox Bi-metal holesaws were used to cut the larger holes:

 

[rswyan]

Drilled and ready to have the rectangular hole cut out:

 

[rswyan]

Completed:

The additional (large, round) holes in the inner two plates (near the bottom) is for routing the hydraulic hoses to the cylinders from the center of grapple into the towers/masts.

 

[Deerherd]

I'm always impressed when someone on here takes on a project of this scope. I have to learn to weld....

I have the same W.R Long grapple, only wider. The one suggestion I have would have is to add an additional angle to the lower jaw. It appears from your drawing that it is straight.

It would increase your brush carrying capacity, put the "spades" on the lower jaw in a better rooting position and give you a better hold on whatever you are carrying. I handle lots of logs and for ease of picking them up it's a great design. Just drive up to the log, give it a little push to make sure it's resting on all the spades and close the grapple. It pulls the log into the lower angle every time.

Here's a photo of what the lower angle looks like. Good luck and nice thread.

Edit: While typing this thread you posted lots of updates so it looks like you are past my suggestion.

 

[rswyan]

Was having an issue with the bandsaw tracking correctly when I cut the chisels for the lower rake ... so I used the Delta Sharpening Center to square them up and put an edge on them.

One on the right is straight out of the saw, the one left has been squared and sharpened ... you could shave with it :

 

[Walkin Horse]

I am blindly gathering parts to make a grapple. I'm still stalled on what the geometry is for the cylinders to close. I will be watching your build so keep posting. Are you making it qa or pin on? I have gotten 2 4" square tubes and a bunch of 3/8 x4" flatbar. Looks like I need some sch 80 pipe.

 

[rswyan]

I'm always impressed when someone on here takes on a project of this scope.

Thanks ...

It will be the first one of this level of complexity that I have done.

I have to learn to weld....

It isn't really all that hard ... particularly with MIG ... a friend who is a welder showed/coached me.

Really learning to weld well is a bit more involved I'm sure

I have the same W.R Long grapple, only wider.

Yes ... I used your pictures along with NHBotanut's) when I was laying it out and modeling it

The one suggestion I have would have is to add an additional angle to the lower jaw. It appears from your drawing that it is straight. It would increase your brush carrying capacity, put the "spades" on the lower jaw in a better rooting position and give you a better hold on whatever you are carrying.

Interesting that you should mention that ... as that was in the original design from a couple years ago ... the one I lost in the hard drive crash.

I took it out this time around as I was starting to get a little concerned about overall weight and was looking to economize.

I handle lots of logs and for ease of picking them up it's a great design. Just drive up to the log, give it a little push to make sure it's resting on all the spades and close the grapple. It pulls the log into the lower angle every time.

Cool ...

I'm really looking forward to using it once it's done ... to the point that I might go ahead use it once I get it finished but wait to paint it until next year ... since it appears I'm running out of good weather for both.

Here's a photo of what the lower angle looks like. Good luck and nice thread.

Thanks !

Edit: While typing this thread you posted lots of updates so it looks like you are past my suggestion.

Yeah ... I welded the lower rake teeth on night before last i think ... but I can always modify it later if need be

 

[rswyan]

I am blindly gathering parts to make a grapple. I'm still stalled on what the geometry is for the cylinders to close.

Yeah ... that was a bit of a mind flock for me ...

I'll try to post a better explanation of how to do it (locating attachment and pivot points) ... might be a few days though. Having access to a CAD program is helpful in figuring it out ... but it isn't a show stopper if you don't.

In terms of ease of fabrication though, you want to these locations to be easy to find/locate ... example: '... drill the hole for the pin 2" in, and 1" down from the top right corner of the plate ..."

I will be watching your build so keep posting.

Will do.

Are you making it qa or pin on?

SSQA ... but I still have to build the tractor side SSQA

I have gotten 2 4" square tubes and a bunch of 3/8 x4" flatbar.

I used 1/2" x 3" flat bar (upper jaw arms, rake teeth) ... but there's no reason 3/8" x 4" couldn't work, providing it's properly reinforced.

The strength is really in the depth (4" in your case)

Looks like I need some sch 80 pipe.

Always handy to have around ...

Pipe (of the same wall thickness) will handle stress/forces better (from any direction) than square or rectangular tube (whose ability to handle forces is more directional than pipe)

 

[rswyan]

Welding up the arms for the upper jaw.

These were clamped four ways to Sunday to prevent/minimize warping, then welded on the one side and allowed to cool ... then the welds were ground flush and the arms were flipped and re-clamped with the now welded side down, and the unwelded side done ... ensuring it was allowed to fully cool before being unclamped.

The areas to be welded were all beveled and welded in three passes to ensure good penetration.

 

[rswyan]

Got the new welding table (4' x 8') set up and the pieces/parts moved onto it:

Ultimately, 30" of the table will be cut off to use for the root rake/grapple and another project (shrub bucket) which leave it as 4' x 5 1/2' ...

 

[rswyan]

Tacking up the inner teeth for the upper jaw:

Just a word on the Harbor Freight magnetic clamps: they are very handy for aligning/holding things ... and are pretty reasonable if you pick them up on sale ...

 

[rswyan]

Lower gussets and rake teeth with chisels welded on the bottom cross bar ...

Starting to get heavy ... and a little dangerous ... the teeth chisels are extremely sharp, as my thumb found out the other night when I accidently bumped it into one of them:

 

[rswyan]

Some of the radius' on the upper jaw arms, which I thought turned out pretty well for minimal time & effort invested:

 

[rswyan]

Tacking on the right side upper jaw arm:

 

[rswyan]

Left side upper jaw arm and one (of three) more cross tube tacked on:

 

[rswyan]

The next cross tube tacked on:

I actually used two ratchet straps on this which I had already taken off when I took the photo.

This piece is pretty heavy ... and I still have one more cross tube to go ...

I was able to stand it up on end by myself ... but I didn't think I could flip it all the way over without loosing control of it ...

Could be time for the boom pole.

The above is where things stand as of this morning.

 

[Xfaxman]

Instead of the boom pole, get a shop crane / cherry picker / engine hoist. :thumbsup:

I use mine a lot.

 

[rswyan]

Instead of the boom pole, get a shop crane / cherry picker / engine hoist. :thumbsup:
View attachment 393012
I use mine a lot.

That would be very handy ... and no fumes ... :thumbsup:

Was talkin' about this with a friend the other night and he suggested a gantry crane with a chain hoist ...

I'd love to have either one ... but space is pretty tight in the shop/shed ... need to get that polebarn finished and a floor poured ... lol ...