Size for "jacking" adapter
 

What size is the square "box" that takes the jack. and how deep is it. I am going to make a better one. ( not happy with the available pads )
Thanks

i think it is a 7/8th box. (inch)

length, dunno

I posted the full specs several years ago if you care to do a search, I don't.

7/8" is close enough, certainly if you had 7/8ths OD (approx) 24 mm), you would have room for fitting without binding.

If you are thinking about forging a piece and you tapered the end a bit, you could get almost 5" depth. There is an easy 3" of unobstructed path at the 7/8ths measurment.

I really don't like the cantalevered design of what is available on the market. If the piece wrapped back under the car to provide a direct lift load wise, I would buy your design in a heartbeat.

Bill, what happened to your usual cheery input? ;) ;) :D

I did search and unforftunately nothing of sizing came up.
I don't like the flat round plate on the available ones.
Zeke, great idea about bending it under, like a "U" shape under the car. I was just thinking about making the part that goes on top ot the jack to fit over the jack so it can't slide, rather just make the jack roll.
But your idea is great, now if someone has the ability to make this that would be a great item !!

7/8" as stated. My adapter is L shaped, 5" x 4".

Didn't meamn to be gruff but there is a ton of info to be found by a little creative searching
lift

I have a friend with a Bridgeport at home in his garage and I
had him machine down a 1 1/4 bye 13 inch bolt to 9/10 tenths
of an inch and mine engages all the way through the boxed rockers and five inchs into the reciever. I got the bolt from our local aircraft surplus THE YARD for $2.00 a lb. I'm not worried about the strength as he broke two machine cutters while cutting the shaft square.

Keith Epperly
87 slant nose turbo look Carrera cabriolet

7/8" cold roled x 6" is what Pelican and everyone else sells. The round is 3" x 3/16".

As for the U shapped idea, talk about one heavy part! At that length, you'd need to gusset it to keep that bended section from collapsing. If your that paraniod, just jack the car up from underneath! Has there been any tragities from using the ones pelican sells?

Hi:

My "jack plate" is very simple. I bought a length of ¾ inch "Weld Stl Tube" from Lowes. I inserted a length of threaded rod into the hollow channel. Try the fit in the store. The diameter I bought fits like it was machined to go in there, kissing all four sides of the interior walls of the steel tube. Do not have access to it now so do not know the length but you can stick it in the jack hole on the car and cut to length. My floor jack has a round pad with crenellations. The "jack plate" fits in the crenulations on the jack. Chock the floor jack's wheels. Place the jack as close as possible to the car so most of the force on the "jack place" is shear. My guess is that this allows more shear and less flex than the Porsche jack with its reported problems.

Disclaimer: Do this at your own risk. I may just be lucky.

Parkin Hunter

Parkin, is that strong enough? The regular kind seem to be cold rolled steel and you are using tubing. That's a huge difference in bending strength and shear strength.

chrisp:

As I said, I may just be lucky.

The rectangular tubing has threaded rod running through the channel in the tubing wich kisses all four walls of the tubing. The rod prevents the tubing from being crushed by the weight and also means the threaded rod as well as the tubing carry the weight. The jack can be placed extremely close to the jack point on the car so I think most of the forces will be shear forces. The vertical vector will not be as good as having ithe jack directly under the car but I believe there will be less bending forces on the bar between the fulcrum at the jack point on the car and the floor jack than the Porsche jack because the jacking point on the floor jack will be closer to the car than the screw in the Porsche jack.

Is it strong enough? Maybe some engineer here wants to run the numbers. I have used this twice to put the car all the way up on four jack stands wihout any problem.

Intuition only to me. Do at your own risk.

chrisp, they are hot rolled. Coldrolled costs too much for the retail price everyone needs to sell it at.

I would be gruff if I was getting his weather right now -- surprised the lines aren't down....


-- An ant-islip surface would be nice too, if anybody is going to marekt an improved version

Just revisiting this. Heavy, huh? Well, I wasn't gonna take it out on the track with me. ;)

Anyway, if the piece were hardened after being forged, it would be plenty strong. And like he says, the leverage on the steel, or what he calls the jacking vector, would be less, not more.

It would need a pad, too, to prevent rolling.