How can I jack a steel post out of the ground?

Question

Following on from this and this question I've got to the point where I am trying to "jack" a pole out of the ground.

I had a spare 3/4" bolt that I thought would be strong enough but unfortunately it bent (see image).

My question: What commonly available (i.e. I can buy it from one of Home Depot or Lowes) 10" x 3/4" rod can I get that will work here? Or what else would you suggest to achieve this goal?

Answer 1

I would use a chain and make sure it is bolted to the post so that the link is touching the post, (both sides ) I.E. threaded bolt through the link with a nut and washer holding it tight to the post. Do this on both sides of the post so you create a loop for the jack to pull up on. You may want to rent a hydraulic post puller.

Answer 2

I can see that this tennis post is becoming a serious PITA.

Let's try to make the job easier rather than pull harder. Are you sure you are above the inner rod that is concreted into the ground? Would it get any easier if you used an angle grinder to cleanly sever the outer pole from the bottom surface (I know it's still rusted out inside).

If we must pull harder. The hardware store has a selection of metal rods but a hardened steel bolt would seem like a good choice. You could go to a machinist supply and describe what you want and get a steel rod with more strength.

Another thought is to get more mechanical advantage. Put in a new bolt, thread over it with a square cylinder. Fix the ends with washers/nuts. Use washers on the inside of the cylinder so it doesn't puncture the metal rod. The assembly will be harder to bend when you jack it.

Or if you can find a good triangular brace (like a joist hanger) mount this upside down and jack on it.

Answer 3

Break the slab and start digging.

Answer 4

Using a heavy duty chain and a lifting hook:

• Drill a hole big enough to fit the hook in the pole, near the ground. Or if you have access to a welder, weld a heavy duty ring or hook to the pole. Or this time, the bolt could still work, as you can fit the hook very close to the pole, and you will work against the shear strength of the ¾" bolt (pretty high) rather than its resistance to bending (bad).
• Lay the chain on top of a wheel, such as an old car tire, that is standing next to the pole. The chain should start vertically, then turn on the wheel and continue horizontally, away from the pole. The tire will provide leverage to pull the pole out.
• Attach the other end of the chain to a truck or to a heavy duty winch attached to something heavy.
• Pull on the chain with the truck or winch.

Go slowly with the truck, as you do not want the chain to snap or the hook to yield.

If the pole will not budge, then it is probably set in concrete, or with anchors, as commentator Jim Stewart said, and you should dig around or just cut the pole and bury the stub.

Answer 5

If you can bend 1/2" angle iron while doing that, then you shouldn't be doing that.

Answer 6

Try steel pipe , can you drill out the hole for 1/2 NPS ? , 3/4 NPS ?, 1" NPS? . Also slide a bolt inside a pipe .High strength bolts like automotive grade 5 , or any left-over head bolts ( likely Gr 5 or stronger) ; all these are more expensive than pipe.