Homemade Rock Bucket w/ Grapple...

[BigDogues]

Hi guys,
I thought that I might share my design for my "light weight" rock bucket and grapple with you. I invite all comments, good, bad or indifferent...
I gave up searching for a rock bucket to fit my Kioti CK25 after some fairly intensive research. Seemed like any rock bucket that was available weighed way too much. Most of the 60" buckets that I had found started at 500 lbs. and went up to more than 800 lbs. for some models. And that was before adding the grapple. When your lifting weight on your tractor is 1200 lbs. that just reduces your capacity way too much right from the get-go. Not to mention most designs have very deep buckets that put the weight even further out from the pivot point. Of course most of those buckets are designed for skidsteers not CUTs. Yes there are a few buckets that are made for CUTs but they tend to be a little expensive for my tastes. (over a $1000 for the bucket and another $450 or more for a grapple ends up resulting to much cost and a low WAF)
So nothing left to do but build my own. My intention is to use 3/4" rod stock spaced 3 3/8" on center for the 17 ribs of my bucket. This will give me a 2 5/8" spacing between the ribs. Anything smaller that falls through I'll get with my landscape rake. The side walls will be 1/4". Should be plenty strong enough as most of the forces will be directed on the edge of the sheet. Naysayers should note that my current bucket side walls are half of that thickness.
I'll be using a 3/4" x 4" cutting edge with 6 weld on bucket teeth to make the digging easier. The weld on shanks should provide me a bit of a material "dam" to help keep the rocks from rolling out. 3" x 3" x 1/4" angle iron is used to tie everything together and give me a place to mount my grapple. I'll be adding a few gussets to strengthen the angle iron under the grapple (not shown in my illustration) My bucket brackets will also be made from the same angle iron (also not shown).
The grapple "kit" is being supplied by Andy Tatro. Andy was good enough to sell me the grapple as a loose item kit so I could place the grapple where I wanted it. (Thanks Andy /forums/images/graemlins/smile.gif)
Estimated grand total for weight... about 400 lbs. /forums/images/graemlins/grin.gif So, considering my current bucket weighs 210 lbs. It's a lifting loss that I can actually live with.
Thanks to everyone that I unashamedly stole ideas from.(especially PineRidge /forums/images/graemlins/smirk.gif) These boards are a great resource! /forums/images/graemlins/laugh.gif
Construction begins next week (hopefully /forums/images/graemlins/tongue.gif) I'll be sure to post many pictures as I go.
-Phil

 

[slowzuki]

I think its great to build your own, but I think you are a bit optimistic on the weight.

 

[RedRocker]

I'm wanting to do the exact same thing. I was looking at a Virnig rock bucket for CUT's, but it's over $700 bucks plus about 200 for shipping. I was thinking of building one similar to it with a grapple. I too want less depth, maybe a foot or so shorter.

 

[BigDogues]

Ahh yes,
I knew I left out something... dimensions! This is not a large bucket. The bucket itself, less the grapple, is under 16" tall, 26" deep (30.5" to the tooth tip), and 60" long.
Material weight as follows...
51' 3/4" rod @ 1.504 lbs./ ft = 76.704 lbs.
14' 3" x 3" x 1/4" angle @ 4.9 lbs./ ft = 68.6 lbs.
3/4" x 4" x 60" cutting edge = est @ 50 lbs.
2 1/4" HRS end plates 358 sq. in. @ .0709 lbs./ sq .in. = 25.38 lbs.
6 bucket teeth w/ shanks @ 3 lbs ea. = 18 lbs.
Grapple assembly with cylinder (I think someone had said it ran about 80 lbs)
Total 318.684 lbs
That leaves about 80 lbs for weld. (Should be enough /forums/images/graemlins/wink.gif)
I think a 400 lb. estimate was pretty conservitive. /forums/images/graemlins/grin.gif

 

[RonMar]

I think you may experience a lot of twisting in your design. IE: I am assuming you have a 4 cylinder FEL so with the arms attached at the bottom near the outside edges and the dump/rollback rams attached near the top above the arms, when you run the bucket into the ground and apply a load out at the cutting edge, the top edge up between the dump rams is going to want to bend along it's length. From your attached pic, I am assuming you are using a 3X3X1/4 piece of angle across the top also?. That may not be strong enough to resist this bending moment and the middle of the tines and cutting edge up forward will sag(tines will twist clockwise in your attached picture). I also didn't read anything in your initial post about gussetts re-enforcing the rods. I think if they are unsupported this will also allow the cutting edge to sag under load as they will just bend. I also believe the bottom angle may bow backward as the middle of the cutting blade runs into immovable objects and pushes directly back on the rods/tines.

I assembled a 60" trash bucket a few weeks ago(see attached pic) and ran into some bending/twisting. I used 4X4X1/4 angle top and bottom with six 4X4X1/4 uprights for the loader attach framework and 4X1/4 side plates. The gussetts that support the tines are 1/4 plate 6" at the base and 15" tall. Tines are 2X2X1/4 box 30" long(20" useable length). I have a 3 cylinder loader so what I saw were the outer tines drooping under load as the top rail bowed along it's length under load. The way I placed the top angle, corner forward, I had to notch it 2" to clear the center mounted dump cylinder. This notch added to the problem but I believe it would still have bent under load to some extent. In hind site, I should have reversed this piece of angle so it was corner aft and then I would not have had to reduce it's strength in this plane by notching it. I added a additional piece of 4X1/4 plate along the top with a 2" overlap(6" total top plate width with 4" in the middle where the cylinder notch is located) to resist this bending. This has removed almost all the flex along the top rail. but even with this reenforcement, it still flexes to some extent under load.

If I were attempting a project such as yours, I would skip the rod entirely as it is not adding much strength particularly when bent, but it is adding a lot of weight. I would have plate waterjet or laser cut into the desired shape for all the tines(similar to your pictured sidewalls but not as deep). To the bottom edge of these plate tines I would weld strap material for side to side re-enforcement to create an inverted "T" profile. This would be fairly easy to create with a torch and hammer. Tack weld the strap to the tine at one end and apply heat along the strap and bend it to the same profile as the tine, welding as you go along. I would then weld these tines to a very boxed/triangulated structure with large top/bottom plates that would resist the bending loads I mentioned above. I think if you re-calculate with tines 1/2 the area of your sidewalls or less and subtract the weight of the 3/4" rod, your weight would not be that much greater(3/4 rod weighs 1.5LB/FT). You will be heavier but the structure will be significantly more ridgid

These things are expensive for a reason, the good ones have a lot of man hours involved in design and fabrication. Good Luck.

 

[rameye]

Phil,,

I'm over in Stoddard if you ever want to practice with your rock bucket! /forums/images/graemlins/cool.gif

ram

 

[BigDogues]

RonMar, Thanks for your input. I think you are absolutely correct that some twisting and flexing is to be expected. Hopefully it will flex back. I don't really plan on using this bucket for any hard digging though. Instead I'll use my regular bucket for the aggressive digging and piling and the rod bucket for sifting and handling brush.
I have attached a picture from a skidsteer bucket manufacturers site that I, umm, borrowed some ideas from. I basically just scaled it way down for my use. I thought about building something along the line of what you are describing, similar to the Virnig Mfg. rock bucket, but opted for the rods. I guess I wanted to keep as much as the work "in house" as possible. /forums/images/graemlins/grin.gif Not to mention almost all of the material I already have laying around.
I am also hoping to pick up some more torsion control when I add my brackets since I have to add another hunk of either angle or channel in the back to attach them to to give me the proper angle. I guess I'll find out soon enough. /forums/images/graemlins/grin.gif

 

[RonMar]

A chunk of rectangular box tube along the top like the one in the picture you attached would be a good idea, that would help a lot with the the bending/twisting. I had contemplated the same thing initially for my fork bucket as that is the way my loader material bucket is constructed but I was trying to keep the top as open as possible to accomidate the brush/logs/stumps I planned to move which it has been performing fantastic on. It has also been pretty good at picking up rocks(has about 3 1/2" between tines) as I have been collecting debris for burn piles on my land. It is hard to judge scale in that picture but the side plates look to be quite thick. Look forward to seeing your version.