I didn't think this would bring out so many ideas. Never thought about using different types of woods. Didn't think short (16") pieces of wood would collapse. Great answers.
Man, those look scary! I would not be crawling under a car resting on those stands. in fact most of the stands posted I wouldn't trust, the engineering skills on these stands is really suspect.
There is no way I would put a car on the mandatory get under it. Get some proper axle stands. They aren't very expensive. It would be way safer for you and the car.
I just did this too. I had to lift the body up real high to take the rear and spring out in one piece. I did mine 16" because the 2x4 comes 96" long, so there was no waste. In the past Ive made them out of "Pallet stickers" I believe they are called. Go behind the Home depot and ask them. They will probably give it to you free..
Geeze, some of you folks should probably stick to Volvos instead of Hot rods based on your replies. And god forbid you ever jack up a car again! The reason these work is from the wide base and top surface. You still have to have them on a level surface. But from all the broken jackstands we have seen here over the years I TOTALLY trust this method over stands.
Unless it's the sunlight & shadows casting doubts so to speak, are goldmountains stands inverted & positioned opposite front to back?
Yeah, and rat rod guys probably say the same thing when they are criticized for the poor engineering they use in their builds. Come on, we should be better than that around here. I would say that the cribs created with 2 x 4's stacked in alternating directions are the best designs, but unless these are made with a hard wood, and I don't think any posted are, at most I would keep the weight at 1000#'s per crib, and that would make me queasy. Let the weight down slow and watch for bending of the boards, and if they bend, don't go with it. You're approaching the structural limits. But these, no way, these are a death trap waiting to happen: The biggest problem is a lack of strength in horizontal forces, those things are gonna collapse like a house of cards. Those wood screws holding things together are not up to the task. And the tops are a simple V pattern with no blocks to keep the wheels from rolling.
Call me crazy, but solid blocking is my preference if I have to get under a car. However I have built the Whatever project similarly to the dirt cars I built in the 70's. Everything was accessible from above. I don't like crawling on the ground, never could make a creeper roll where I wanted to go, and besides that I've never been that agile. Getting up was hard when I was younger. Today it's next to impossible. I have to plan ahead so I have a prop. Having said that, I do have good axle stands. I need them these days to be able to stand upright when working on the Whatever project.
More ideas. As I mentioned in this thread Gibbon Fiberglass even made some out of GASP! Fiberglass!?! The material was about 3/16" thick. Got the car about 16" off the deck. Worked awesome assembling my touring Technical - Cribbing Boxes | The H.A.M.B. (jalopyjournal.com)
Which has greater structural strength, wood or fiberglass? "The compression strength of industrial fiberglass is almost 17 times that of the same species of structural timber." https://www.strongwell.com/news/industrial-fiberglass-versus-metal-and-wood/
I was going to reply to your post, but @Blues4U bet me to it and is correct in his comments. No sideways support, - little screws into the end grain won’t hold up under lateral movement. the idea is there, the execution is a little sketchy….…… the cribbing ideas work on compression, and by having the flat surface on each other, helps to eliminate the lateral problems.
and then there was this thread……….. https://www.jalopyjournal.com/forum/threads/how-can-you-be-safe.1298844/ Funnily enough, when we were kids we couldn’t afford jack stands, so got big solid hardwood blocks. Got sick of dragging them around so when the cheap Chinese ones became available, we bought some………
Thank you for the input. I admit that the cross bars screwed into the end grain isn't very strong, the boards across the top and bottom should work out.
All you would need to do is replace the 2x crossbars on the ends with a solid sheet of 1/2" plywood and it would tie it all together and triangulate things. Airframes and ships have used wood construction for ever. I do like your inverted top as well. Good idea. As usual you are overthinking things. THOUSANDS of folks have used these types of stands over the years. I am 110% about safety and this method done right, as posted and proven is just fine. (just look at the other thread I posted)
I much prefer my stacked 2x8s to using jack stands. When I do use jack stands, I stack 6x6s under the axle as a safety measure…
Blah blah blah , most hardwood is prone to splitting. Pine & fir are more flexible railroad ties are generally white wood (SPF ) power/ phone poles. are whitewood .. Look it up !Holding up 1000 lbs with pine or for cribbing is perfectly safe !
I know these next pictures are going to make some of you cower in fear, run to your mommies and hide under the bed in the fetal position, the pure horror of my wooden cribs holding something up without collapsing ! What's that thread, things that have always worked until someone that has never did it says that it can't work, ha ha ha ha ha ha ha ha ha
Have these been forgotten? Granted, Montgomery Wards and the JC Penney Auto Shop have been defunct for a few decades now, but...:
Can they survive a couple good whacks with a sledgehammer from a 45-degree angle. And still be used safely.
"Softwood" simply means it came out of a coniferous tree. Pine is a softwood, but so is yew. "Hardwood" simply means it came out of a deciduous tree. Oak is a hardwood, but so is balsa. @Blues4U puts it as two words, so that presumably includes hard softwoods and soft hardwoods? But: what kind of compressive strength are we talking anyway? Strange how no actual numbers have yet been mentioned? If it's 2x4s (not a standard size here — our closest is 50x114 i.e. 2x4½) then there is a total bearing area of 4x4x4=64 square inches per corner. Using @2OLD2FAST 's figure of 1000lbs, that's less than 16psi. That is less than 1/9 of the compressive strength of balsa! Even a soft softwood will carry that load 300 times over. The failure mode of this thing isn't going to be compressive failure. It isn't going to get crushed to splinters. It's probably going to be some combination of shear and bending failure, especially if the stack is tall enough for buckling to become an issue. My first thoughts: Keep the unsupported span of the topmost members as short as possible. Double up the topmost members: laminate and nail/screw liberally. Pay attention to the shear resistance between layers. (Consider grooving and split rings between successive layers, using a single long heavy bolt to hold each corner together. That means that changing the height would require some disassembly/reassembly and bolts of different lengths.)
If by now anyone is in doubt with regards to jack stands vs. cribbing, I believe rustydusty by simply stacking & properly nailing/screwing each layer gets my vote.
Or you can go this route. Very handy and sturdy. https://www.eastwood.com/eastwood-d...ickedid=650350156047&wickedsource=google&wv=4
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