Crib blocks

[wsmm]

Mostly I see crib blocks being used under tires. Is it save to use them under frame locations and or axle locations?
Thanks for the help.
Bill

 

[Jim.ME]

Mostly I see crib blocks being used under tires. Is it save to use them under frame locations and or axle locations?
Thanks for the help.
Bill

Please describe what are you call a crib block? To me timber blocks like 4 x 4 or 6 x 6 about 2 feet long are cribbing blocks. Stacked two wide with the next layers alternating 90 degrees to the ones below would be fine under a frame. Singles just stacked one on the other, not recommended.

 

[Janicholson]

If it is concrete or cinder blocks you refer to, they are not to be used for holding up vehicles or equipment. They work OK in walls. Just not done. They crumble and drop the load from point loading. Wood cribbing

, and jack stands OK

 

[wsmm]

I was referring to timber cribs of either 2x4 4x4 4x6 6x6 screwed together or fastened some how together. NO concrete or cinder blocks involved.

 

[Jim.ME]

I was referring to timber cribs of either 2x4 4x4 4x6 6x6 screwed together or fastened some how together. NO concrete or cinder blocks involved.

timber cribbing should be fine

 

[showcrop]

I was referring to timber cribs of either 2x4 4x4 4x6 6x6 screwed together or fastened some how together. NO concrete or cinder blocks involved.

Those are not cribs because they are not designed for stacking as in the picture that janicholson posted. The blocks that you describe are most likely to be used under tires, but only when in width of at least two times wider than the tires. and in a height of no more than half the width.

 

[Janicholson]

The cribbing I found an image for are just stacked like shown, no fasteners. Jim

 

[Jim.ME]

The cribbing I found an image for are just stacked like shown, no fasteners. Jim

Also as I posted, alternating layers at 90 degrees to each other.

 

[caterpillar guy]

I like to use bigger blocks size wise like 8x8 or 12x12 uses fewer blocks and builds up faster. 4x4's built up to a couple feet high are a slow process. 12x12's will get it done with fewer blocks and be just as solid with less wiggle places in the cribbing. I also like the bottom blocks to be about 3 feet long if there is room without being under foot. I just saw them out of small logs if I need new ones with the chainsaw.

 

[Fixingfarmer]

cribbing to do it right just like the picture like that takes a lot of space. I am not saying it’s wrong for a second. I honestly have not done that once ever. I use mostly metal stands that take up less space including some big 20 ton stands with a nice spot to catch the frame not just a flat round top. When we did big stuff like a 992 axle or 777 haul truck needed to be lifted so the tire guy could work on it we used solid lumber. Like half an oak tree solid a 2x4 but dimensional and in feet not inches. We never got killed doing it that way and for the most part especially on the loaders you could position the cribbing then position the machine not much scooting of that piece of lumber if you could help it. Find an Amish sawmill and acquire some chunks you cant get at Lowe’s

 

[jniolon]

these are just like mine. Mine are 12x12x12... You'll use up all your 2x4s. Take care jacking your ride to insert these.; I have to do the front first then the rear.. My floor jack is extended completely with a 4x4 block on the pad to get the tire clearance I need

j

 

[sms]

Mostly I see crib blocks being used under tires. Is it save to use them under frame locations and or axle locations?
Thanks for the help.
Bill

I am a strong believer in properly used solid wood cribbing. However I did have a bulldozer on cribbing with the tracks off and was under it with a 3/4 drive breaker bar trying to get a stubborn bolt loose and twisted/slid the whole machine on the blocking, luckily it stayed on the blocking. Always be careful.

 

[wp6529]

A few references:

https://docs.google.com/presentatio...0oVCTCIt3Wlppp_Kfc/mobilepresent#slide=id.p68

https://www.fema.gov/pdf/emergency/usr/module2a.pdf

https://www.montgomerycountymd.gov/...d_Stabilization_Equipment_(DRAFT_Nov2014).pdf

 

[Fixingfarmer]

Boy I don’t know on the last one of those from Montgomery county. Be very careful if standing the cribbing vertical like that they show it spread out nice and crushed into the perpendicular cribbing but I’ve seen people especially split wood that way if they don’t use the perpendicular on the top and bottom. Also if this is needed why bother with the load bearing number that is higher since you must use the perpendicular one anyway? Good pictures though!

 

[wp6529]

Boy I don’t know on the last one of those from Montgomery county. Be very careful if standing the cribbing vertical like that they show it spread out nice and crushed into the perpendicular cribbing but I’ve seen people especially split wood that way if they don’t use the perpendicular on the top and bottom. Also if this is needed why bother with the load bearing number that is higher since you must use the perpendicular one anyway? Good pictures though!

Later in that document they cover the vertical shoring and show examples where there are multiple vertical elements, thus why you have the top beam to distribute the load across the vertical piles. Also note that it is a doc for emergency services and not necessarily what you would do on a nice controlled building site. Either way these docs give a good overview of using they typical cribbing stacks and and idea of the significant loads they can carry.