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      01-21-2012, 02:03 PM   #1
Trev
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Engineer help needed to refine Lift bar design.

Sketched up this concept of a central lift bar. Looking for engineer's to poke holes in the concept & help crystallize final design.

This idea aims solves two problems,
1. For those of us that changes wheels at track, while it is possible to lift both wheels off ground using current F/R jack points, it doesn't allow for jackstands to be make process safe. With this idea one floor jack lifts side evenly, jackstands can be slid into receptacle pockets.

2. For those of us without a lift, using two of these bars you could quickly lift car up onto jackstands.

Brief solidworks study using 2x2" square tube steel with a gusset showed a deflection of 2mm at jackpads. This is with a 4000lbs load.
If you consider 4000lbs is 20% greater than total car weight & If your only lifting one side the weight seen by bar will be upto 50% less than calculated.


Attachment 634147

Goal of this study is to create a CAD drawing for open publication to this list. If someone wants one of these made they should be able to take plans to a engineering firm Or we'll make one for them @ Time & Materials rate.

Last edited by Trev; 02-23-2013 at 01:33 AM.
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      01-22-2012, 01:03 AM   #2
Ron Stygar
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Quote:
Originally Posted by Trev View Post
Sketched up this concept of a central lift bar. Looking for engineer's to poke holes in the concept & help crystallize final design.
AC has cross beam one:

page 6
http://www.kremit.ru/images/upload/12price.pdf

page 15
http://www.ac-hydraulic.dk/pdf/manuals/dk13-20.pdf
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      01-22-2012, 10:19 AM   #3
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I really don't see the point of this.

using the center OE points front and rear, jack stands are easy.
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      01-22-2012, 02:59 PM   #4
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Quote:
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I really don't see the point of this.

using the center OE points front and rear, jack stands are easy.
Me neither. No space at the sides in a home garage.
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      01-22-2012, 03:26 PM   #5
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Me neither. I dont see how it is gonna work because it will be so low to the ground that you will have a hard time getting a jack to the center point. Plus it is too big and bulky. If anything, i would make something like a plate which place on the jack and still ultilize the mfgr recommended jack points
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      01-23-2012, 06:43 PM   #6
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As someone correctly assumed this brace would lift from the side. It sits front to rear picking up vehicle using existing jackpad locations.
I discounted the front under engine central jackpoint for most people as its so far under there for regular jacks. Plus if your lowered that'll be a very specialized jack.

At this point i've talked with enough people that i'm convinced a 2x2" square wall tube spanning 46" (distance from jackpads) will be sufficient. Will post pictures of finished product.
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      01-25-2012, 01:09 PM   #7
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The Z's sit so low that I don't know how the 2x2 tube is going to fit between the lift point and the jack. I have to drive onto wood blocks just to get enough clearance for my jack - and that's without a 2" spacer in the way.
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      02-07-2012, 02:27 PM   #8
esqu1re
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I think it's a great idea. Be sure to update when you have it worked up!
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      02-16-2012, 07:06 PM   #9
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I'm a Design Engineer and its nice to see end users to come up with solutions of their own, safety first though. If you need an engineering shop for drawings, prototypes or 3D work send me a message, I am always willing to aid fellow Coupe drivers. I work at a product design & development firm, info at ideasmachine.com. Good luck on your project!
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      09-12-2012, 07:17 PM   #10
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Check this out.

I think the blocks of wood at the front wheels may be on the wrong side for a rear wheel drive car...driveway looks a bit sloped.

Pinning is a good idea to prevent anything from rolling off the jack.


http://www.fordgtforum.com/forums/sh...without-a-lift


Last edited by Punko; 09-12-2012 at 07:33 PM.
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      10-02-2012, 10:11 AM   #11
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This is pretty smart, for people that swap there front wheels on and off constantly, you pretty much finish jacking up to wheels at a time instead of doing it side by side and you can put jack stands down without damaging the car in anyway
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      12-20-2012, 02:51 PM   #12
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http://forums.rennlist.com/rennforum...d-setting.html

Another method.
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      01-18-2013, 07:24 PM   #13
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I had 2x lifting beams made....just need to get them home...won't fit in the coupe.

2" total height, plus jack height. All made out of square tube, also has some flexibility to fit my Audi A6 jacking points.

Each beam probably weights in at 30 pounds, 62" long.

It should just barely fit without having to drive up onto any ramps, will see.

Once I get them home and try them out I will post pics.

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      06-01-2013, 06:40 PM   #14
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Works like a charm.

I do have to drive up a couple boards to get enough clearance.

The jack stands I bought are solid.




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      06-01-2013, 08:30 PM   #15
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Nice...I need to do this....where did you get the beams from?

Quote:
Originally Posted by Punko View Post
Works like a charm.

I do have to drive up a couple boards to get enough clearance.

The jack stands I bought are solid.




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      06-01-2013, 08:36 PM   #16
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They are just 2x2 square tube stock with 1 3/4 sleeved through it....ends up pretty heavy.

Any steel supply shop would have it.
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      06-01-2013, 11:30 PM   #17
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I like it! Thanks for the idea.
I only have side access in my garage.
Been jacking the car up by the pinch welds for years with a 1 foot 2x4 in place of the jack head, then adapting standard jack stands by putting pieces of 1x2 in the car's jack points.

Punko, have you tested it to see how much flex there is without the 1 3/4 sleeved through it?
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      06-02-2013, 09:13 AM   #18
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Never tried with just 2" square tube.

On my wifes Audi A6 avant the bar bends about a 1/4"....that car weights more and the jack points are further apart.
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      06-02-2013, 09:36 AM   #19
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Punko- Where did you get those jack stand? What brand are they? They look very sturdy, and I like the fact that they have flat tops.
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      06-02-2013, 11:37 AM   #20
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They are great jack stands....but they were expen$ive.

They are Esco flat top jack stands. I bought them ASE deals.

I would feel comfortable under the car with them fully extended.
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      07-06-2013, 01:17 PM   #21
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How does the current design not allow jackstands?

Jack car from center rear - rear lifts up
Install 2 rear side jackstands
Jack car from center front - front lifts up
Install 2 front side jackstands

I dont see how this idea is any easier? Either way you are still jacking up the car twice and putting jackstands under it... just seems like more complications.
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      07-07-2013, 01:37 PM   #22
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I found getting to the rear or front middle jack points difficult, perhaps with a low profile jack with a long reach you can get to it easily without going up on boards etc.
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