Brush and Tine Grapple Bucket Help ??

dtd24 · Dec 2, 2006

Am I the only one who gets excited by solid modeling?

tlbuser · Dec 6, 2006

shaley said:
Tl, Your grapple looks good and I like the teeth cut into face. I'd have to see how it closes on the bucket to determine how effective they are. I'm set up for a 2.5" cylinder which will put out 12,000 lbs. so I'm using 1" hinge pins.
Do you think a single cylinder 36" wide grapple arm will work almost as well as two 18" arms. I'd sure like to keep it simple. Although, the extra cylinder is only $49 at Surplus Center.

Well, work load has put a little strain on my "free time". And, now my new autocad 2007 program isn't running

I don't have a stress analysis program though so I was doing a little swaging on the dimensions. Also considered using round "torque tubes" instead of square, but I've got square "in stock". Would be easy enough to move the pin diameter up one or two before sending it off to the plasma cutter. I added teeth because the one that I've used doesn't grip round objects as well as I would like.

And yes, from what I've seen and used I can't find any real purpose for a double grapple. Simpler is almost always better, especially when you have to fix it!
Sending the .dwg arm file by PM

tlbuser · Dec 6, 2006

shaley said:
I think I'm going to go with an open back with a bent plate for stiffness and an open back for vision. Here is the bucket weighing in about 320lb. Just for a idea of scale the top tube is 4x4.

Yea, I like that! Still 6" spacing on the tines? How about adding some smaller rod or bar in between the tines to "sift" smaller rocks out ?

tlbuser · Dec 6, 2006

dtd24 said:
Am I the only one who gets excited by solid modeling?

NOPE, That's one big reason I upgraded to autocad 2007, Now, if only we can figure out why it's not acting right

shaley · Dec 6, 2006

tlbuser said:
Yea, I like that! Still 6" spacing on the tines? How about adding some smaller rod or bar in between the tines to "sift" smaller rocks out ?

Do you think it would be effective if I added some small round stand-offs with a groove, facing horizontal (flat) in between the tines say about 1" long so you could stretch a sheet of expanded metal across the flat area and tuck it down in between the tines and over the stand-offs for fine sifting

tlbuser · Dec 7, 2006

Didn't think about that concept. The finer the mesh.......maybe. Could use the tilt to shake the bucket. Hmmm, you maybe on to a good add-on feature. I was just thinking about general use. Like after I burn down a pile and pick up the left-overs. Or using the tines as a rake, especially if I make the grapple easily removable.

shaley · Dec 7, 2006

Tl, is 6" spacing close enough on the tines or do I need closer

Here's my latest delima. How do I pick up multiple post or poles such as 8" or 10" type used for pole barn or boat houses. If they are piled together I could see rolling the grapple forward and grabbing a cluster. What if they are laying flat on the ground some 8" here an 12" over there. When you tilt the tines and open the grapple the poles that are in the bucket roll forward and fall out. I guess you could just regather the new pile of mixed poles.

tlbuser · Dec 7, 2006

Really depends on what you think all of your uses will be. The only reason for tighter spacing would be to keep smaller objects from falling through. But yes, for the basic design 6" should be perfectly OK. If you're needs change, you could always weld / add something to narrow the gap.

Yea, round objects are tough to handle more than one at a time. Using the grapple to "pick one" out of a pile takes practice. IMO, getting off the ground is easier because then you just slide the forks under one, two, three.......however many the bucket will hold.

schmism · Dec 7, 2006

what do you guys plan on useing for fingers?

1/2 - 3/8 or 1/4 material

plasma cut by hand (template) in your own shop?

waterjet/cnc plasma at a machineshop?

starting with flat bar stock (3/8x3") or cutting from sheet (plate)

bar stock is hard to find at my local scrap place, but hunks of sheet (plate) are common....

shaley · Dec 7, 2006

schmism said:
what do you guys plan on useing for fingers?

1/2 - 3/8 or 1/4 material

plasma cut by hand (template) in your own shop?

waterjet/cnc plasma at a machineshop?

starting with flat bar stock (3/8x3") or cutting from sheet (plate)

bar stock is hard to find at my local scrap place, but hunks of sheet (plate) are common....

1/2 plate on the outside 3/8 tines. 4x4 x0.187 tube at top 1/4 formed plate at rear. I thought I'd just send the DXF to a shop and have it CNC flame cut or either LASER cut and do the assy.
I'll be glad to share the CAD plans. I just want to build it right the first time.