Another DIY Grapple

[IvanS]

Tittle pretty well says it all. This is a brush grapple that I've been working on the last couple of weekends. Ready for paint and hydraulics. Made from primarily 3/8" bar stock and sized to fit my Kubota B3300SU - 48" wide and weighs around #300 by my calculations. My LA504 loader has the Kubota quick attach system and this is designed to work with that. Sorry for the terrible picture quality, will get some better photos later this week.

I couldn't resist the temptation to have the logo water jet cut into the front plate. It wasn't very expensive - hope Kubota doesn't mind

 

[motoman3b]

Looks sweet :thumbsup:

 

[adirondackmtnman]

NICE!!!:thumbsup:

 

[ovrszd]

Great workmanship. Love the logo.

Is that a 2" cylinder, hard to tell in photos?? You may want to consider some trussing on the claw. My 2" cylinder bent 1/2x4" flat bar that is trussed. When it'll bend is when one side of the claw is gripping a larger item than the other side. All that twist is concentrated in the claw design and adds stress in wierd places. Easier to fix now than have to straighten and reinforce after it's bent. Keep in mind the grapple's power to clamp is determined by the tractor's hydraulic capacity, not by the tractor's size or lift capacity. So in practical use your tractor can clamp just as tight as my M9540, just maybe not as quickly.

Another issue is that you need something to protect the cylinder. For example, if you clamped onto a stump that would fit in the "V" shaped hole under the cylinder you have a high chance of bending the cylinder.

Again, great job, looks great!!!

 

[stuckmotor]

Beautiful workmanship. Reminds me of how much I miss BattleBots.

 

[IvanS]

Great workmanship. Love the logo.

Is that a 2" cylinder, hard to tell in photos?? You may want to consider some trussing on the claw. My 2" cylinder bent 1/2x4" flat bar that is trussed. When it'll bend is when one side of the claw is gripping a larger item than the other side. All that twist is concentrated in the claw design and adds stress in wierd places. Easier to fix now than have to straighten and reinforce after it's bent. Keep in mind the grapple's power to clamp is determined by the tractor's hydraulic capacity, not by the tractor's size or lift capacity. So in practical use your tractor can clamp just as tight as my M9540, just maybe not as quickly.

Another issue is that you need something to protect the cylinder. For example, if you clamped onto a stump that would fit in the "V" shaped hole under the cylinder you have a high chance of bending the cylinder.

Again, great job, looks great!!!

You are correct, 2" cylinder and I am going to add some gussets to the side arms of the claw as you suggested. Had not thought about the cylinders expose from underneath; I will consider that before painting. Thanks for the compliment.

 

[IvanS]

Beautiful workmanship. Reminds me of how much I miss BattleBots.

That's exactly what my son mentioned while I was building it.

 

[ovrszd]

You are correct, 2" cylinder and I am going to add some gussets to the side arms of the claw as you suggested. Had not thought about the cylinders expose from underneath; I will consider that before painting. Thanks for the compliment.

Not trying to hijack your thread, just demonstrating a point with pictures. See how my right set of claws is only gripping with one tooth. The outer, far right tooth isn't doing anything. When loaded like that the force of the hydraulics has to be distributed across the claw structure or it will twist it. Also in these photos you can see how I protected my cylinders with a shield.

Again, great project. Good for the Soul isn't it?? :thumbsup:

 

[IvanS]

Got some better pictures this morning:

Looking for a local source for sandblasting before I paint, hope that will lead to longer paint life.

 

[ovrszd]

Lookin Good!!! Don't spend too much time and money on paint. You're gonna scrape it all off anyway!!!

 

[murphy1244]

You may want to weld some mesh to the back of the grapple to protect your tractor when ramming into brush

 

[IvanS]

Thanks for the thought Murph, I already have the mesh sitting in the shop... I am a bit curious about branches, sticks, etc. getting caught in the mesh and tearing it up but I guess that's better then them making it to the radiator.

 

[Boris1]

Looks awesome! How much would you say was

Tied up in materials?

 

[94BULLITT]

Looks good.

 

[bubbacuse77]

How wide is it? Did you get the logo cut with Plasma or water jet?

 

[bubbacuse77]

Sorry I guess I should read before posting. your first thread said it all........................Nice work.

 

[IvanS]

Looks awesome! How much would you say was

Tied up in materials?

I'd say about $425 including the cylinder and the cutting of the logo.

 

[sittinstill]

I just bought material to start my grapple for my bucket and your hinge pin for your grapple is a great idea! I'm going to change my design to be like that, if you don't mind me asking what size is your pin that u used to go threw the base of the top grapple hinge?
Thanks

 

[IvanS]

I just bought material to start my grapple for my bucket and your hinge pin for your grapple is a great idea! I'm going to change my design to be like that, if you don't mind me asking what size is your pin that u used to go threw the base of the top grapple hinge?
Thanks

If you are asking about the pivot for the grapple portion, it's a 3/4" bolt. The "hinge tube" that spans the width of the grapple is 2" diameter 3/16" wall tubing with a 1" long plug turned on the lathe and welded into the ends of the tubing. I tapped the plug and the grapple arm and then put a set screw into the plug to keep the bolt from backing out. The bolt passes through a piece of 1/4" wall DOM with a grease zerk in it for the pivot bracket on the frame. Hope my explanation makes sense.

 

[sittinstill]

Yes it does thanks.
I bought a tube that's appox 2" x 1/4 wall and a shaft that runs threw it snug. So I going to use the whole length like you instead if making individual hinges for both sides. Simpler and effective. Thanks. Gonna start this weakend and ill try to post some pics of progress.