wooden car stand (cribbing) project

Couple of these and you can roll it around your garage.

 

You mean put the wooden car stands on top of the HF rollers?....think I would just use a regular dolly to lift it and move it to the location I want.

For folks reading this thread....here's one of the original DIYs.

http://www.myturbodiesel.com/wiki/w...r-raising-the-car-in-addition-to-jack-stands/

 

Yeah i guess. Just naturally does not seem strong but you do make a great point haha.

 

Common screws have no shear value

 

Yup. That's what my dad did in his garage. It wasn't the exact ones in the link I sent but the idea is there.

Yes I was getting at the ability to move it. To me if you can't move the car why not just get jack stands?

 

use framing nails. much stronger than screws

 

I'm not a framer, so please explain to me (saying it a sincere way) how framing nails holds the wood better than wood screws? The framing nails have stronger metal so it doesn't shear right? But I thought the idea is to get compression bonding between the two wood material. So screws would hold the wood tightly together while the wood glue cures. Leaving the screw in is an added bonus. Should I even care about shearing if the glue is present and also would I care since majority of the force is downward towards the ground instead of lateral. I don't know how much racking would occur. I know the traditional design...there's very little chance of racking unless it was really poorly constructed.

P.s. I only have a couple of wood clamps...not many nor big...so screws works best for me.

Jack stands would be to easy wouldn't it? Just kidding... the reason is with wheel car stands, you get much more clearance and the jack stands would get in the way of most work underneath. They sell wheel car stands, but they are $500+... these are about $80 to $90 to build. I'm recovering from sore/injured back...so I don't want to aggravate it, but so a regular dolly which I have from Costco...the foldable kinda can lift 50lbs no problem.

 

Makes sense. I use truck jack stands on my Civic and I could limbo under it if I tried. But yes sometimes jack stands get in the way.

 

The sheer strength is much greater and that's what you want here. Not something to hold til the glue dries. I would even use glue. With humidity and temp changes and the load that will be on and off these I bet the glue will fail quickly. YouTube some nails vs screws videos. Screws are good for sheetrock and decking. Most everything else when you want strength use nails.

 

Use PL Premium and the glue will not fail

 

pudge151, huh? haha.. Glue can create extremely strong wood bonds.

OP,
The nail vs. screw thing.. I started to try and explain but, instead there's some decent articles already, that get more in depth.
Here's a couple.
http://lifehacker.com/5990779/screws-vs-nails-when-do-you-use-one-or-the-other
http://www.builderonline.com/building/dear-builders-engineer-nails-or-screws_o

Really when it comes down to it, it depends on the particular screw/nail/wood and project you're talking about.. It's not a cut dry this is better than that answer. They each have a purpose they were designed for.

This project is one of those things you can get technical on.

I do think DoorDing made a solid point tho, "How much will it cost if the cribbing fails?".

 

I digged up some datasheet numbrs:

PL Premium
Compression Shear Strength, ASTM D3498: Douglas Fir to Douglas Fir plywood Dry Lumber Bonding 638 psi (4.4 N/mm2 )

Titebond II premium 3,750 psi (+ Maple to Maple (ASTM D-905) Bond Strength at 70°F)

So I think I will stick with titebond...I'm sure both are good.

I answered that with other structural screws that are 2 1/2" long hundred pack.

But really no one has answered me why the required shear force? From the original design everything is downward force. I don't see lateral forces involved. The truck is being loaded onto the car stand...it's downward force. There's no lateral force (significant) unless one just releases the hydraulic jack down on the car stand super fast and one wheel hits the wooded wheel stand first and then there's lateral movement. But each wheel stand will have over dozens of screws and glue. So the sum of these (regular deck) screws and glue...do you think it will still shear off?

I would counter sink so the screw would not stick out of the surface. Far as welding, you name a shop that would build for custom wheel stand for less than $500 let alone $250. This is supposed to be a good reliable way to jack the vehicle up...many pro garage shops use them in their everyday use. Rhino Ramps, I don't dig driving up and then having the ramp move or slide. Also the ramps are longer and again will get in the way. Finally...Rhino ramps gives you a measly 6.5 inches in lift.

What's the lateral load on a static to low dynamic load from jacking up the truck and resting it onto the wood car stand?

I didn't want to use nails because I didn't want to pilot hole and then a nail, but same time I don't want to split the wood.

I'm going to look up my deck screws I have and see what is the shear force. I believe in numbers from reliable companies...

 

I usually use Titebond 3 for finishing and PL Premium for construction

 

I agree with you, but given the shear force and the amount of glue I will apply...do you think either design there will be shear failure? Just debating with you for more sound advice. I gave up on saving weight since I won't be carrying it...just dolly it around...so the old design I lose an inch...but no question about racking. The new design, I'm not sure... didn't get a reply from my old professor, so hopefully Jonah or another structural engineer can comment as well.

Remember that the PL premium or Titebond is supposed to be strong as wood, so how do you think any of this will shear apart? I'll have a 8 to 12 screws per row of screws and then there's glue.

 

Why not just use some 4x4's, you could screw/glue the top ones together so they wouldn't shift, Put a couple 2x's for stops if you wanted.. Then you completely eliminate all these concerns/questions you're having. And easier to store, when you're done you could stack them against the wall or something out of the way.

 

or buy jack stands haha

 

That there will hold up a house. 4x4's are neither cheap nor light. This is what they use to crib bridges and houses...4x4 and 6x6. Wouldn't I have to worry about the shearing force if these aren't glued together or screwed together? 2x4's have been used for a long time for cars....just wasn't sure if my design would make sense...and wanted some structural engineers and architect who actually done design to tell me. It's been too long since I've been in the lab to look at wood failure with a deflection meter to see how much force versus wing span to fail.

 

Already explained why Oz.. jack stands get in the way and only lift the car by the frame rails and not much higher... wooded car stands are by the wheels... so I get almost 2 ft of clearance.

 

Won't you need regular jack stands as well for any work that involves removing the wheels..?

Like anything suspension or steering related.

 

Use 6x6's and through bolt the corners a piece of 3/4" redi rod with timber washers