Lift bars
#16
Here is his response:
Jonathan--
I did some quick calcs on rollover for various stands, during a discussion on "which stands to buy". The 3-ton stands have a smaller footprint obviously, and at full extension the overturning moment requires just 175# in either direct lateral or direct longitudinal force to get them over center. That's with car on 4 stands at their full extension, level ground, and ASSumes concrete. So you'd really want the 6-tons stands for their extra stability if you are doing anything on the car that includes that kind of pulling or pushing.
But... A lot depends on the jack you are using. Most common jacks have a max height of somewhere less than 20 inches. Without the liftbars, getting the car onto the 6-ton stands means either adding a 3"-thick block on the jack's pad, or taking the first step onto a 3-ton stand. Then a lateral lift to get a six-ton under the the other front corner, and back to the first point to replace the 3-ton with a 6-ton. Lifting the rear is relatively easy, except that with the fronts up high on the 6-tons there's mot that much room to get the jack under the rear crossmember for that last lift. Even with room for the jack, there's almost no room to pump the handle. That's how I ended up with four each of the 3-ton and 6-ton stands.
Using the liftbars doesn't buy you much WRT help on jack height. There's -maybe- 2" difference between the jack pad height and the saddles where you put your stands. You don't get the advantage of the cantilever when jacking any more so are limited to jack height alone plus liftbar height as far as total height available. Further, you MUST lift the car is steps when using the liftbars. Try to pick one side up to full height, and you have a serious risk of it rolling off the first liftbar as you pick up the second side. Liftbar owners have lready reported accidents from this. I've seen the liftbars at Rob's but dont have exact dimensions; consider that with the lift pad on the car as small as it is (~3") and relatively 'soft', a liftbar height of 1.5" from jack pad to saddle means a rollover at 45º. The liftbars are taller than that though, so you get to do a little trig to see what step angles are safe when lifting the car side-to-side. Bottom line is that the first lift on one side will undoubtedly be lower than the lowest 6-ton height. So your minimum jackstand requirement will be a pair of 3-ton for the first side, a pair of 6-ton for the second side, another pair of 6-ton for the second lift on the first side.
-----
Twenty-odd years ago I bought a company in a rural town in Illinois. I was visiting there one time when a neighbor woman cam running over screaming for help. Hubby had jacked up their car in the garage to work on it, no stands. It rolled off the jack and pinned him against the garage wall, crushing his ribcage and suffocating him. He was dead before she found him. It was a bit of work lifting the car off of him in the tight garage, and an experience that left an indelible mark on me regarding jacks, jackstands, and remembering the physics and the gravity. There's no room for error.
I did some quick calcs on rollover for various stands, during a discussion on "which stands to buy". The 3-ton stands have a smaller footprint obviously, and at full extension the overturning moment requires just 175# in either direct lateral or direct longitudinal force to get them over center. That's with car on 4 stands at their full extension, level ground, and ASSumes concrete. So you'd really want the 6-tons stands for their extra stability if you are doing anything on the car that includes that kind of pulling or pushing.
But... A lot depends on the jack you are using. Most common jacks have a max height of somewhere less than 20 inches. Without the liftbars, getting the car onto the 6-ton stands means either adding a 3"-thick block on the jack's pad, or taking the first step onto a 3-ton stand. Then a lateral lift to get a six-ton under the the other front corner, and back to the first point to replace the 3-ton with a 6-ton. Lifting the rear is relatively easy, except that with the fronts up high on the 6-tons there's mot that much room to get the jack under the rear crossmember for that last lift. Even with room for the jack, there's almost no room to pump the handle. That's how I ended up with four each of the 3-ton and 6-ton stands.
Using the liftbars doesn't buy you much WRT help on jack height. There's -maybe- 2" difference between the jack pad height and the saddles where you put your stands. You don't get the advantage of the cantilever when jacking any more so are limited to jack height alone plus liftbar height as far as total height available. Further, you MUST lift the car is steps when using the liftbars. Try to pick one side up to full height, and you have a serious risk of it rolling off the first liftbar as you pick up the second side. Liftbar owners have lready reported accidents from this. I've seen the liftbars at Rob's but dont have exact dimensions; consider that with the lift pad on the car as small as it is (~3") and relatively 'soft', a liftbar height of 1.5" from jack pad to saddle means a rollover at 45º. The liftbars are taller than that though, so you get to do a little trig to see what step angles are safe when lifting the car side-to-side. Bottom line is that the first lift on one side will undoubtedly be lower than the lowest 6-ton height. So your minimum jackstand requirement will be a pair of 3-ton for the first side, a pair of 6-ton for the second side, another pair of 6-ton for the second lift on the first side.
-----
Twenty-odd years ago I bought a company in a rural town in Illinois. I was visiting there one time when a neighbor woman cam running over screaming for help. Hubby had jacked up their car in the garage to work on it, no stands. It rolled off the jack and pinned him against the garage wall, crushing his ribcage and suffocating him. He was dead before she found him. It was a bit of work lifting the car off of him in the tight garage, and an experience that left an indelible mark on me regarding jacks, jackstands, and remembering the physics and the gravity. There's no room for error.
#17
Thanks for all the input and tips guys.
I have new stands from Advance auto, and an old heavy 3-ton jack, and a new 2-ton from Advance auto.
Garage is new, with a nice smooth level floor....
I have new stands from Advance auto, and an old heavy 3-ton jack, and a new 2-ton from Advance auto.
Garage is new, with a nice smooth level floor....
#18
Playing around...I had started a blog on Pellican about my car, and myself, as I am new to the 928. If allowed, I will post a link....I will be starting a thread here soon...
#19
cant wait for pictures! i need to get a nice LOW race jack so i can do the lift bars all at once. right now i have to lift the front end up, stick wood under the tire , then i can get the lift bar on the jack and it will fit under the car.....
#21
I'm not a mod or anything but I think that might be frowned upon. Maybe just link the pics?
#22
yea, I guess if I had to ask....
I'll start a new thread here, and "cut and paste"..lol
Perhaps this weekend...I have a ton of pics...a few of the guys at SITM got to see them....
Most of the feed back I initially got on Pelli, was to scrap it, but I am a stubborn fool, and am determined to revive her...
I'll start a new thread here, and "cut and paste"..lol
Perhaps this weekend...I have a ton of pics...a few of the guys at SITM got to see them....
Most of the feed back I initially got on Pelli, was to scrap it, but I am a stubborn fool, and am determined to revive her...
#24
hmm............. never even heard of a "lift bar" ... must be one of those American Expressions (like Hood .... trunk .... ) ??
(smile ... if I could find the wee things .....)
I just installed a four post ramp ... bought S/H ... about $500 !!
(smile ... if I could find the wee things .....)
I just installed a four post ramp ... bought S/H ... about $500 !!
#28
OK ... I get the picture ............ remind me NOT to rush out and order a set !!
ta
(reminds me of the catalogues you get with all those really usefull gadgets that you don't actually need to buy !!)
have a nice day ... time for ZZZ's here !!
ta
(reminds me of the catalogues you get with all those really usefull gadgets that you don't actually need to buy !!)
have a nice day ... time for ZZZ's here !!
#29
After adding the cost for all the jacks, stands, lift bars, etc. AND getting too old to get under the 928 (not to mention back out multiple times) finally got a two post lift.
Really the only way to go, wish I had bought one YEARS ago!
Dave
Really the only way to go, wish I had bought one YEARS ago!
Dave