I work with moving machine tools on a somewhat regular basis and all the supporting cribbing is wood. I would not hesitate to put a 20,000# machine on four of those blocks. Getting the car up on the blocks is a little hairy but not unsafe to personal safety. Once on the blocks I would rather be under that then a car supported by jack stands.

 

Dean

forget the 2x10 - what you are interested in is the three smaller pieces - are they 4x2

Some crude assumptions,
the smaller pieces are 3"wide and 10" long (and 2" high but that's irrelevant)
Assume the timber is a Western white wood, machine stress graded, Utility grade ( couldn't find anything weaker in my collections of various Timber design standards )
This has a compressive strength perp to the grain of 1.1N/mm2
Assume the middle piece of 3x2 takes 50% of the wheel load and the outer pieces take 25% each.

The 10" long by 3"wide peice has a compressive strength (perp to the grain) of 250*75*1.1 = 20625N = 2102 Kg = 2 Tons near enough. Therfore each wheel stand has a capacity of 4 tonnes.

I haven't included any of the allowable factors for short term loading, direct bearing, etc. but these could possibly increase the above capacity by a factor of 2.

Fortunately wood is renewable or I'ld have admonished you for unneccesarily wasting materials LOL.

 

Don't knock shear pins - the shear capacity (double shear) of the 12mm pins in my 2 Ton jackstands is (most pessimistic choice of steel) 2.5Tons and is more likely to be in the order of 6 tons.

Stella


mmmmmmmmmmmmmmmmmmmmm

 

Hell, get enough beers in me and I'd be willing to get close enough to at least pass Dean the tools, and grab his ankles and scream when the car fell on him.

 

Dean- I think you are marketing this to the wrong crowd on RL. I see lots of potential from a group that will THANK you for your efforts!

 

Not sure how to interpret a post with "Grab his Ankles" and "Scream" in the same sentence.






If the mechanic in white had slid further into the car, her 'airbags' would have cushioned the fall of the Beeemer.

 

A softer version of this:

 

Can I buy you a life insurance policy me as the benafactor?