Remove an LB without Dynamite?

busman

busman

Senior Member
Location
Northern Virginia
Occupation
Master Electrician / Electrical Engineer
Need so "real world" help if possible. Need to remove a mogul LB to re-route the conduit (easy to remove the conductors back to a JB). Details follow:

2" GRC
Saltwater Environment (50' from the Atlantic Ocean)
Field cut Threads on the GRC
No apparent Koppr-shield (although required)

Question: How hard to remove the LB. I do have 24" Pump Pliers and 24" Pipe Wrench. I do not have a torch, but could probably come up with one. Do have WD-40. Working VERY remotely from Supply Houses/Hardware stores.

Thoughts? Your experience is greatly valued by me. I do VERY little GRC.

Thanks as always.

Mark
 
I once had to remove an aluminum LB from aluminum conduit that was laying in the ground.

I had to make two diagonal cuts across the threaded hubs to break it loose enough to turn.
 
Thanks all for the quick info as this is tomorrow's job. I have sawzall, not a grinder. I thought I might need the diagonal cuts. Will WD-40 help at all? You are all invaluable.

I don't know if a photo helps. Sorry it was not in the OP. FWIW, I can get the cover off the LB to spray the threads with WD-40.

1698269327260.png

Thanks,

Mark
 
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busman said:
Thanks all for the quick info as this is tomorrow's job. I have sawzall, not a grinder. I thought I might need the diagonal cuts. Will WD-40 help at all? You are all invaluable.

I don't know if a photo helps. Sorry it was not in the OP. FWIW, I can get the cover off the LB to spray the threads with WD-40.

View attachment 2568153

Thanks,

Mark
Click to expand...
Sorry. I own multiple grinder, just not here with me on the road.

Mark
 
Take the cover off and make a diagonal cut (Sawzall or grinder) right where the screw was right down to the conduit. Spray it up with WD-40, then with a big screwdriver and hammer pry the slot open. That should open up the threads allowing you to unscrew it.

-Hal
 
hbiss said:
Take the cover off and make a diagonal cut (Sawzall or grinder) right where the screw was right down to the conduit. Spray it up with WD-40, then with a big screwdriver and hammer pry the slot open. That should open up the threads allowing you to unscrew it.

-Hal
Click to expand...
Never had any luck trying to pry the slot open, but good luck driving a cold chisel down the slot to spit the piece.
 
I agree with cutting off the LB a little beyond the threads, and then cutting a slot inline with the conduit so that it can be spread apart with a pry bar or screwdriver. A hacksaw may give you better control on the slot so you don't butcher the threads. If it's still stuck, you can hammer on a chisel angled in the slot in the direction to unscrew the piece of LB as well as spread it. If you have a helper to back up the conduit with something heavy such as the head of a sledgehammer that can allowable greater impact from the chisel. Of course an air chisel would be ideal.
Heat on the piece of LB and/or penetrating oil, (e.g. PB Blaster) would help.

I just see that Don mentioned a cold chisel as well. If a chisel is used, hitting it at an angle instead of straight down as was mentioned above can help. This is an old trick used to remove heavily rusted nuts such as those on exhaust systems.

If you have access to cut another slot on the opposite side, that could help split it if you're not able to otherwise.
 
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I still kinda like the dynamite idea. It blowed up real good! :D
 
busman said:
Heading for bed. You are all fantastic. I will let you know how it goes.

Thanks.

Mar
Click to expand...
You should try it first.... But now you can throw that angle grinder in your truck. Its not the lunar module. Hammer works too. And good ol big azz...
 
Thanks to all. If I was starting from home, the angle grinder and threader would go on the truck, but I'm working out of a hotel room and only have what I have. Your comments are all very much appreciated.

Mark
 
WD40 works for the simplest of issues.

Real penetrating oil applied a day or two before then whack the threaded area with a 3 lb hammer while holding another 3 lb hammer on the opposite side.

Cut a slot or two and apply your WD40. Hammer treatment.
Cut the LB off just past the threads then slot what's left of it.
I hope you have a lot of blades, That type of LB is tough.
 
If you end up boogering the threads or if it just won't come loose, cut off the threads completely, deburr, and use a compression fitting on the cut end of the GRC. FEDEX overnight will get you what you need from McMaster-Carr:

www.mcmaster.com

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.
www.mcmaster.com www.mcmaster.com
or
www.mcmaster.com

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.
www.mcmaster.com www.mcmaster.com


SceneryDriver
 
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