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Author Topic: Ideas for loosening tight bolts from concrete base section of tower??  (Read 5954 times)
AG5T
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« on: May 20, 2012, 04:10:41 PM »

I am rebuilding a tower and concrete base for a tower that was severely damaged several years ago in Hurricane Ike. I believe I am going to be able to salvage everything but rebuiding has been a slow process. Unfortunately the gemquad antenna was destroyed by the hurricane. I am hoping to replace it with a mini-beam type antenna. What I am looking for right now is a way to loosen two nuts that were attached to rebar that was added to a large cube of concrete years ago when the tower was originally mounted. I was able to get one of the three nuts off the rebar, but the other two are so tight they won't even budge. A friend suggested a mixed of fingernail polish and something else (sorry I can't remember the other ingredient). The nuts are on the rebar, above the concrete block, but about an inch or so from the top of the rebar. I thought about getting a hacksaw, but then I would have uneven bars. I have tried a heavy pipe wrench, but not much success (except for the first one that came off). Anyone have any ideas on how to tackle this? Thanks.
« Last Edit: May 21, 2012, 03:33:37 PM by AG5T » Logged
K2OWK
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« Reply #1 on: May 20, 2012, 04:21:45 PM »

Try penetrating oil left on for a few hours, then tap the bolt lightly with a hammer and see if this will remove it. If you can not remove it, you can use a grinder to grind it off flush with the re-bar.

Hope this will help.

73s

K2OWK
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WB4SPT
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« Reply #2 on: May 20, 2012, 04:34:14 PM »

"Bolts on rebar"?   As in U bolts?  Are they rusted together?  I don't have a good visual here.  Anyway, the use of a metal cutoff blade on a 4" angle grinder will work wonders, and fast.  I only discovered angle grinders a few years ago;  I should not have waited so long.
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K1CJS
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« Reply #3 on: May 20, 2012, 05:11:45 PM »

I'll say the same thing--bolts?  Do you mean the nuts that are probably holding the tower base to the bolts that have been attached to the rebar?  For that, there is a tool called a nut buster.  It will cut through the nut and spread it so it can be more easily be removed from the bolt.

Now, if it's a bolt that screws into a baseplate, how about heating it with a propane pencil flame torch?  Don't heat it so much that it gets red hot, but sometimes a little heat will do the trick.  If that don't work, how about just cutting the bolthead off and drilling out the stub?  If you're careful and get the drill bit properly centered, you can get it to the point that the stub will be able to be taken out of the plate after you've drilled the core out of it.
« Last Edit: May 20, 2012, 05:16:47 PM by K1CJS » Logged
AD4U
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« Reply #4 on: May 20, 2012, 06:17:06 PM »

Heat ALWAYS works.  Not a little propane blow torch but an oxygen acetylene torch.  Do not cut the fastner, just heat the nut until it turns dull to cherry red and quickly use a wrench to get it off.  It will come right off - every time.

Dick  AD4U
« Last Edit: May 23, 2012, 06:22:28 PM by AD4U » Logged
KCJ9091
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« Reply #5 on: May 20, 2012, 06:35:06 PM »

Nut splitter:  http://www.northerntool.com/shop/tools/product_34573_34573
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AJ3O
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« Reply #6 on: May 20, 2012, 06:58:31 PM »




First spray PB blaster on the threads, wait 30 minutes, then spray again. After 15-20 more minutes, wipe the surface clean and try the proper size wrench or buster bar. If this still does not work, use the tool noted above.
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K9KJM
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« Reply #7 on: May 20, 2012, 09:16:12 PM »

KROIL  by Kano labs is by far the best product to use, Far better than PB Blaster, etc.

http://www.kanolabs.com/msn/

If that fails, As pointed out, Some heat from a torch will do the job.  Even if you have to destroy the nuts, With a nut splitter, etc  No big deal You can buy new nuts for the bolts.

You do NOT want to cut the bolt off!  If you do that, You lose all use of that big hunk of concrete!
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W6CD
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« Reply #8 on: May 20, 2012, 09:40:54 PM »

apply PB blaster in the morning, again in the afernoon, and some more in the evening - next day use the proper wrench and remove the nuts.  If still won't come loose - repeat the application.  After yet another day if still won't loosen, heat with a torch.
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K1CJS
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« Reply #9 on: May 21, 2012, 08:59:37 AM »

Heat ALWAYS works.  Not a little propane blow torch but an oxygen acetylene torch.  Do not cut the fastner, just heat the nut until it turns cherry red and use a wrench to get it off.  It will come right off - every time.

Pardon me if I'm wrong, but that may affect the tower structure if any part of the base (of either the tower or the tower baseplate) were to be heat treated.  The absolute last thing you want to do with a tower is to weaken the metal attachment points, and excess heat may just do that.
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AD4U
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« Reply #10 on: May 21, 2012, 09:15:51 AM »

Heat ALWAYS works.  Not a little propane blow torch but an oxygen acetylene torch.  Do not cut the fastner, just heat the nut until it turns cherry red and use a wrench to get it off.  It will come right off - every time.

Pardon me if I'm wrong, but that may affect the tower structure if any part of the base (of either the tower or the tower baseplate) were to be heat treated.  The absolute last thing you want to do with a tower is to weaken the metal attachment points, and excess heat may just do that.


"Heat" is like most other tools.  In the hands of someone who knows how to use it, it works well.  On the other hand some people can tear up a cast iron anvil with a banana.

Dick  AD4U
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W8JX
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« Reply #11 on: May 21, 2012, 01:13:31 PM »

Heat ALWAYS works.  Not a little propane blow torch but an oxygen acetylene torch.  Do not cut the fastner, just heat the nut until it turns cherry red and use a wrench to get it off.  It will come right off - every time.

Pardon me if I'm wrong, but that may affect the tower structure if any part of the base (of either the tower or the tower baseplate) were to be heat treated.  The absolute last thing you want to do with a tower is to weaken the metal attachment points, and excess heat may just do that.

With the proper torch is is VERY easy to do safely. This is not a job for a propane torch though. And forget the PB blaster too. You need a oxy-acetylene cutting torch that can spot heat nut cherry red in mere seconds and bolt will come right off. You do it this way so not only can you focus heat but by heating very quicky and the nut swells with heat faster than stud it is on and it breaks free easily. 
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AG5T
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« Reply #12 on: May 21, 2012, 03:32:45 PM »

Correction (thanks) - I meant to say nut, not bolt, that's attached to the rebar, but I think everyone understood. It's a large nut, maybe 1 to 1/2 inches in diameter. Thanks for all the great suggestions.
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K6UJ
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« Reply #13 on: May 21, 2012, 08:39:07 PM »

Take an open end wrench that fits the nut, (preferable) or a large crescent wrench,
slide on a 4 foot length of pipe that the wrench fits inside, and pull on this cheater.
It should break loose with this much mechanical advantage easily.

Bob
K6UJ

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K5LXP
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« Reply #14 on: May 21, 2012, 08:55:17 PM »

Take an open end wrench that fits the nut, (preferable) or a large crescent wrench, slide on a 4 foot length of pipe that the wrench fits inside, and pull on this cheater. It should break loose with this much mechanical advantage easily.

Or round off the nut, or break the wrench (the former most likely with a crescent).  Heat or a nut splitter works like magic.


Mark K5LXP
Albuquerque, NM

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