Something like this?



Has anyone got one lying around they would part with?

Thanks,

Iain

Have you thought about making one? We did something fairly similar for a single seater (circa 250kg) and we even had one that had no fancy pivots etc. and was still useable by one person.

It's fairly straightforward unless it's for a heavy car and you start adding multiple pivot points etc.

quote:

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Originally posted by PSpirine
Have you thought about making one? We did something fairly similar for a single seater (circa 250kg) and we even had one that had no fancy pivots etc. and was still useable by one person.

It's fairly straightforward unless it's for a heavy car and you start adding multiple pivot points etc.

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They are pretty easy to make. I made one years ago when i worked in the development shop designing 'green machine' sweepers

The key geometry is to make the angle between the handle and the ground less than 90 degrees (so that when the jack is lowered / handle raised, the handle 'leans forward' over the body of the jack), so that when you pull it through its arc to the ground it goes over centre. I think I used an 80 degree included angle.

The only other critical dimension is the length of the sections which set the height of the floor when the jack is raised. the one in the picture looks like it has been geared up from the handle to the front end vertical.

everything else is pretty much just to hold the key points together in the right place - a classic spaceframe, just like a chassis!

Looks like a classic project to make a flat carbdoard mock up first to check the vertical geometry, then move into 3D

you can actually make them even more basic if you fit jacking points to the car into which a section of tube / turned boss can slot. You see the brackets on a lot of racing cars (particularly cobras, fitted on the bumper mounts) and the jack is just a long 'L' shape, with wheels at the corner, and the included angle less than 90 degrees.

Look for a classic 'pit stop' photo from the '50s or '60s and you'll probably see this basic version in use.

Hope that helps.




or the 'basic' version (and Rob Walker's very nice 250 SWB!):



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[Edited on 26/3/11 by Mistron]

[Edited on 26/3/11 by Mistron]

Thank you guys, looks like i have a mini project on the go