pallet forks or grapple for boulders?

[Builder]

Just got a boulder retaining wall job. 5' high x 120' long. Most boulders are 2'-3' in diameter with a few 4 footers, so I'm looking at 2-3 layers of boulders. Plenty of room to work from below. I could carry them in my LB115 bucket or even my M-7040 bucket, but "placing" them is a different story. I'd rather work out of the M-7040 because it's smaller.

Seems like pallet forks would work really well with their adjustable tines to slide them under the boulders, but a grapple bucket might be even better. Only thing I'm worried about is bending bottom tines on grapple? The grapple I'm considering is a Titan 72" with 5/8" thick bottom tines, so it's a pretty HD grapple.

My thought was to ditch out a level ledge for 1st layer, fabric, then backfill behind first layer to build ledge for second layer, fabric behind 2nd layer, then more fill, then 3rd layer.

Thoughts/suggestions?

 

[Duffster]

I think you are thinking from the wrong end of the TLB.

 

[Builder]

I think you are thinking from the wrong end of the TLB.

I don't think so. As I said in my first post, I will be using backhoe end to level the ditch they sit in. What you probably don't understand (and I didn't say) is they need to be carried from the boulder pile about 1/5 mile to where the wall is to be built.

I'd rather not use backhoe bucket to clamp the boulders against the boom because it might mark them up a lot, too.

 

[HCJtractor]

I have used my grapple to move boulders and place them where needed. Really works great. I would think you have more control over the boulder with a grapple than a fork. Being able to clamp it and tilt, curl it would allow better dexterity in placing it. As far a bending it, that should not be problem. A fork may slide under it better to pick it up, but that would be the only advantage, in my opinion. The grapple would also hold it tighter when transporting the boulder and not allow it to slip off.

 

[IslandTractor]

Grapple, grapple, grapple.

Pallet forks would be a pain as you'd need to secure the load each time. Grapples do this sort of work easily so long as the boulders are big enough that they don't slip between the tines. That would usually not be a a problem with wall building but if it is you could easily put a barrier in place on the bottom of the grapple to hold them in.

 

[BX2230Dude]

You need something like this to rotate and set each rock precisely.

Rock Jaw Rock Moving Equipment

It's kind of pricey, you could probably fab something up from a pair of good logging tongs for a lot less.

 

[J_J]

How about one of these.

http://www.starhilljawz.com/video3.html

Star Hill JAWZ

 

[IslandTractor]

There are two separate tasks, moving the rocks from pile to wall and then placing them precisely. I think OP was focused on the first. Grapple or grapple bucket is the way to go for transport. He has a TLB so maybe just a thumb on the BH would be a cost effective placement tool.

 

[Builder]

I don't have enough money in the job for an "active" backhoe thumb, although a simple fixed thumb would be better than nutin'.

 

[CurlyDave]

There are two separate tasks, moving the rocks from pile to wall and then placing them precisely. I think OP was focused on the first. Grapple or grapple bucket is the way to go for transport. He has a TLB so maybe just a thumb on the BH would be a cost effective placement tool.

You are right. I have both a grapple and a thumb and the combination works quite well to build retaining walls.

My machine is only 43 hp, so I am not able to handle 4' or rocks and even 3' ones have to be more like 2' x 2' x 3' for me to pick them up, but the thumb is the only way to go for placement with a BH.

The grapple will work for placing the larger rocks, but there is going to be difficulty placing the smaller ones accurately enough, especially if you want to decide what face should be out.

I doubt you are going to want to carry the 4' ones in your M-7040 bucket. A 4' cube of concrete would weigh 8000 lbs, and rock is more dense than concrete.