Best Floor Jack
Safety Car
Joined: Sep 2015
Posts: 4,785
Likes: 1,417
Man... I remember having to work under my cars when they were on jack stands. But... Since we bought the house in the country 9 years ago, and I had a real 2 post lift put in, I'm never going back...
I might rethink the using of wood as a cross beam for your jacks. The engineer in me just doesn't like wood for that application. Especially when you can see cracks in the side blocks. Just saying.
I might rethink the using of wood as a cross beam for your jacks. The engineer in me just doesn't like wood for that application. Especially when you can see cracks in the side blocks. Just saying.
E-Ray, 3LZ, ZER, LIFT
Joined: Sep 2007
Posts: 35,045
Likes: 12,411
From: NE South Carolina
Man... I remember having to work under my cars when they were on jack stands. But... Since we bought the house in the country 9 years ago, and I had a real 2 post lift put in, I'm never going back...
I might rethink the using of wood as a cross beam for your jacks. The engineer in me just doesn't like wood for that application. Especially when you can see cracks in the side blocks. Just saying.
I might rethink the using of wood as a cross beam for your jacks. The engineer in me just doesn't like wood for that application. Especially when you can see cracks in the side blocks. Just saying.
At the end of this PDF you'll fine several page of stress calculations. The minimum safety factor is 15:1! That is the worst case, it's probably more like 35:1. In fact there is a reference where you could calculate the stress on a cross beam. Wood is very safe and holding up your house over much longer spans!
http://netwelding.com/Jacking_A_C7.pdf
As an engineer you may appreciate the math!
Perhaps of interest, I calculated how thin a steel cross brace could be made so it would fit the front or rear when used with my large jack without having to first jack up the side for clearance. It was about 3/8 inch thick x 5 inches wide, not for the load capability but as with many beam calculations to limit the amount of deflection! With thin rubber pads on the ends it can work. Used my 2X6 wood cross beam on my C6 for many years. Structurally well under any stress limit.
Last edited by JerryU; Mar 6, 2016 at 09:30 AM.
