Generally we work flat ground, but occasionally we have to set up on a slight grade. It’s always tough for me to get my first layer of cribbing level without leaving a big air gap between the cribbing and the ground. I was going to cut some wedges out of some oak 8x8’s I had milled. What’s the best angle to cut on these for slight grades. Or is there a better way?
Cribbing on a slope
- Thread starter Treeline
- Start date
Reach
Been here much more than a while
- Location
- Atglen, PA
We just stack cribbing and let a gap; place one piece of cribbing across the slope on the “downhill” side and then stack on top of it so the rest of the stack is flat.
This picture isn’t the greatest, but it will give you an idea of one of the ways we do it.
This picture isn’t the greatest, but it will give you an idea of one of the ways we do it.
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deevo
Been here a while
- Location
- Horseshoe Valley, Ontario, Canada
I carry some 2x10’s 2x6’s and 2x4’s on both cranes in some circumstances helps level off the sides or ends if needed. I’ll see if I have any pics
Fivepoints
Carpal tunnel level member
- Location
- East of Huntsville, AL
Also make sure like the picture reach posted, put the downhill piece tall enough that the outrigger pad slopes up on the downhill side. Keeps things from unexpectedly sliding and if it should sink some you are still ok.
I used 5x5 lumber and 2.5x5 to crib with. Its nice because it all stacks together easily. With the 2.5s and the 5s we can setup on a hill very easy without a huge gap. I always like a lot of ground contact spreading the load.
I used 5x5 lumber and 2.5x5 to crib with. Its nice because it all stacks together easily. With the 2.5s and the 5s we can setup on a hill very easy without a huge gap. I always like a lot of ground contact spreading the load.
This is basically how we do now. I don’t mind having a small gap with my oak 8x8’s but I normally only carry pine 4x6’s with me and the gap makes me feel uneasy with those. It’s just a 40 ton crane but I’m kind of paranoid on the setup. Nobody ever tipped a crane because their outriggers were too stable.
Reach
Been here much more than a while
- Location
- Atglen, PA
Change out all your cribbing with Oak 4x6s and you’re good to go, no need for the pine (I don’t trust pine for cribbing ever) and you won’t need to carry two sizes either.
- Location
- Retired in Minneapolis
I had cribbing milled in rectangles...8x10, etc.and 4', 3' and 2' lengths
This gave me a lot of dimensions to choose for the bottom layer when leveling. It also eliminated most 'shims' in 2x dimensions to level up.
This gave me a lot of dimensions to choose for the bottom layer when leveling. It also eliminated most 'shims' in 2x dimensions to level up.
southsoundtree
Been here much more than a while
- Location
- Olympia, WA
How much void space between, and bridging across dunnage is legit?
Reach
Been here much more than a while
- Location
- Atglen, PA
I don’t have any “official” numbers, just our standard practices. We avoid space between the cribbing sticks, and stack them tight (maybe 1” between them on occasion?) together on the layer that bridges the void below. They never span more than about 3/4 of their length, so probably 24-28” max span?
Also, we are typically stacking on top of this at least one or two more layers to ensure even weight distribution across the whole layer, so that the load is not concentrated in the center of the span, which could cause cribbing breakage.
Reach
Been here much more than a while
- Location
- Atglen, PA
The White Oak, in my opinion.
- Location
- Fort Lauderdale
I've been using white oak boards for a while now. They hold up real well. I have my base layers are 12in wide 4 inch thick and 5 feet long. I also have 12x4x3ft for stacking up and also some 12x3x3ft and 12x2x3ft for spacers and fillers boards. I suggest getting some 1/2 in all thread and drill through side with some bolts and washers helps with splitting.
Sand bags… that’s freaking brilliant. I’ll definitely be throwing a few on the crane.
deevo
Been here a while
- Location
- Horseshoe Valley, Ontario, Canada
i have Various size cribbing on my cranes. Sorry for the sideways pic
Steve Connally
Been here much more than a while
- Location
- Suffolk, Virginia
So for my wedges I have 5x7 synthetic structural members. 24" long and maybe 1/2 at the skinny end. I could probably tell you what that angle is but it would probably leave a scar from thinking about it. The simple guy says turn it on its side and cut from one corner opposite to the other end. I like wedges, I prefer not to fill gaps with sand or other movable, shiftable items. Did shoring and cribbing on the fire department for many years. Wasn't ever acceptable for US to operate like that. The verdict is still out on the synthetic stuff though. Used it some in the FD but I haven't decided if crane dunnage is the best application.
I’ve cribbed on several sloped areas, but every time has been on permeable lawn surfaces, or some sort of understory type ground. In these types of areas I’ve always been able to, and feel very comfortable with, digging into the slope and leveling out a pad for my normal cribbing.
In some cases, we’ve lifted up a patch of sod, set up the cribbing, and laid everything back in place when finished with very little to no trace.
In some cases, we’ve lifted up a patch of sod, set up the cribbing, and laid everything back in place when finished with very little to no trace.
We do this when feasible but a lot of times we’re on pavement in the road and I think it would be frowned upon to cut the asphalt haha
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