Gentlemen:
I’ve got a job that requires the removal and reinstallation of 28 porch columns on a German style ranch house in central Texas. I think that I saw a tip or short article several years ago about a jack that was constructed of 2″ X 8″s or 2″ x 10″s laminated with plywood that were temporarily used to jack a porch roof sufficiently to remove and replace the columns. I assume it had a birds mouth on the upper end which would work fine with the porch construction I’m dealing with. Am I mis remembering? Any one else use this method?
Thanks,
Joe C
Replies
Yeah - I've built and used similar jack posts. Start with two 4x4's, the total length of them slightly less than the length from your pressure point on the object to be jacked to the ground. Build a "cage" from 2x8 and 2x6 that the 4x4 can slide inside. Leave an opening on one side of the cage. Slide one of the 4x4s inside the cage and attach it so the top is even with the bottom of the opening. Slide the other 4x4 in from the other end and leave it loose. Put your jack in between the two 4x4s. A couple of metal plates would help.
I've also used this type device without a jack, but used wood shims instead for light/short lifts.
There is an inexpensive (reasonably) screw jack that has two ends that you can nail/screw/bolt to pieces of 2x to make a jack. I got a couple from (I'm pretty sure) Aircraft Spruce a few years back, though I don't see them listed there now.
cheap jack
Not totally sure I'm following your "need", but I ve used the following to jack up girders or such to shim or what not.
If th height of item to be jacked is (randomly) 100" above the ground, I cut one 2x at slightly shorter, say 99" and one slightly longer, say 100.5".
Nail boards together, flush at one end, half way up-if you were to stand the two up together they would be flush at the bottom and nailed half way up from the bottom.
At this point you make a square cut line roughly half way up the longer board, above nailing in lower half. I add two nails above cut line to hold upper half of longer board in place close enough to cut line to allow longer board to hinge on shorter board. ONLY CUT THROUGH LONGER BOARD leaving shorter board intact.
Not sure I'm articulating this all that well....
At this juncture you should be able to stand 'jack' under item to be lifted. Bend at hinge point placing base (lower nailed half)on ground and top of longer board under item to be lifted. I usually toe nail so it stays put.
The result should be the shorter piece is leaning at an angle and the longer piece is hinged, lower half nailed to shorter piece and upper half hinged at cut and attached to item to be jacked. Now you just push the uncut shorter piece against hinge point straightening longer piece. I will sort of snap together, lifting item up. Then I just nail a "keeper" nail at the top of two boards to hold them together. When you are done just pull keeper nail and push against hinge to lower item.
Will lift an amazing amount of weight. I've never felt the need to use more than 2x4s but size of item to be lifted would dictate.
Cheap Jack
This might have been better and shorter.