Nut Splitters and rusted keel nuts

tom52

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Is it possible to split an M24 nut (which is 36mm from flat to flat) using a manual nut splitter if you don't have the strength of a gorilla ?
It seems awfully big to me, anyone split M24s by hand ?
 
The nut splitters I'm familiar with use a large screw to drive in the chisel so I don't think size would be particularly important.
 
I had to split eight nuts on a 1 1/8 inch thread earlier this year, I could not get a large splitter. I started with a dremel cutting disk and finished with a 2 lb hammer and cold chisel. It took a bit of effort but a lot less effort than anticipated.
 
I would drill a line of closely spaced small holes between the bolt and the edge of the nut to weaken it. Then drive a sharp, good quality cold chisel in and spring the nut apart.
 
Save yourself a lot of time and effort and use a 4 1/2 inch angle grinder to cut down both sides of the bolt to remove two sides of the nut, but try not to damage the bolt threads too much. A sharp tap with a hammer to the remaining nut bits will loosen it for you.
 
I would drill a line of closely spaced small holes between the bolt and the edge of the nut to weaken it. Then drive a sharp, good quality cold chisel in and spring the nut apart.

What he said; you can get hydraulic splitters but they're pretty bulky and getting them on a keel bolt isn't likely to be possible.
 
Save yourself a lot of time and effort and use a 4 1/2 inch angle grinder to cut down both sides of the bolt to remove two sides of the nut, but try not to damage the bolt threads too much. A sharp tap with a hammer to the remaining nut bits will loosen it for you.
On a GRP boat I'd be careful about the heat generated: angle grinders can have the steel being cut glowing red hot - well above the temperature for igniting resin. Can be done, but bit by bit and cooling with water every few seconds cutting.

The OP has not said why he wants to take the nuts off. If it is just surface rust and the hull-keel joint is sound often better to leave well alone on GRP boats, just clean rust and protect with paint or resin.
 
Cold chisel and a lump hammer. You could start with a grinder, dremil or drill if you like but the chisel will do it quite quickly and access is rarely good for those other devices.
 
Is it possible to split an M24 nut (which is 36mm from flat to flat) using a manual nut splitter if you don't have the strength of a gorilla ?
It seems awfully big to me, anyone split M24s by hand ?

Peeps that have replaced the nuts on Moody keel bolts (also 24mm) say that the studs usually come out with the nuts. Have you tried undoing them? Easier to remove them in a vice. They also comment that the rust is surprisingly superficial when cleaned off.

Had a similar experience trying to remove an old quadrant the other day. Found an angle grinder reluctant to the rust. Hit it with a hammer and was rewarded with flakes of rust 1/4" thick. But underneath it was in surprisingly good nick.
 
Further to previous similar advice:

I'd be surprised if you could get a manual one that big. An hydraulic one would be easy if it would fit. If space is a real issue then cut a groove with a chisel (*yes!) and then when nearly through give the nut a tap or a turn and it'll yield.

*Use a BIG hammer and a top quality long small sharp cold chisel. Cutting downwards works well. Using too small a hammer &/or a blunt chisel risks damage nearby. Wear welders gloves or hold the chisel in mole grips. Eye protection is an absolute must.
 
Depends to what extent you need to preserve the bolt/stud-you can carefully cut away one of the angles on the nut either with an angle grinder or hacksaw which will lead to some thread loss on the stud.
The use of red heat to the end of the nut usually works as well
 
Why do people give advice that a) cannot possibly work and b) causes so much mess and damage that it cannot be justified?

How can an angle grinder slit a nut in a bilge? At best you might slit a small part of one flat, not worth the trouble.

Never, ever, grind anything inside a boat unless it is a bare hull that has to be completed. Hot steel grindings will burn through varnish and upholstery, fly everywhere and then go rusty. Pre-drilling the nut will help but a sharp chisel and a heavy hammer causes least damage and is probably the most effective.

I took metalwork at school in the 1950s. Our first task was to chisel a length of round bar to produce a flat on it, then another one at right angles to it, using only a hammer, chisel and files. I was 13 years old and small. Safety glasses had not been invented and gloves were not issued. I soon learned how to use a hammer and chisel properly.

All this assumes that a good quality socket spanner, extension and a big, long tommy bar won't shift it.
 
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I've used angle grinders to remove difficult nuts. Use a cutting disc and cut down (i.e parallel to the bolt). Works a treat.
If you're working in a boat, a dust sheet or two solves the problem of sparks of metal flying around.
 
On a GRP boat I'd be careful about the heat generated: angle grinders can have the steel being cut glowing red hot - well above the temperature for igniting resin. Can be done, but bit by bit and cooling with water every few seconds cutting.

The OP has not said why he wants to take the nuts off. If it is just surface rust and the hull-keel joint is sound often better to leave well alone on GRP boats, just clean rust and protect with paint or resin.

Use 1mm discs, less heat and it will be over in seconds, without setting the boat on fire.
 
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