Author Topic: Best manual cutting tool for hardened bolts?  (Read 8368 times)

BlueMR2

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Best manual cutting tool for hardened bolts?
« on: March 09, 2014, 03:21:43 PM »
So, my car failed to get an alignment at the shop (and it needs one bad enough to not be driveable until I can get one done) yesterday because the rear toe arm eccentric bolts are frozen in place.  I've got spare arms and bolts off a rearend I bought for parts, I just need to install them (sounds easy, eh?).  However, it looks like I'm going to have to cut the bolts (through the bushing) to free the current ones from the car as I can't get them to budge.  The space is too small to fit my usual hacksaw in there.  I hear a sawzall works great for this task.  I'd prefer a manual tool with a similar profile though.  Suggestions?

Exflyboy

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Re: Best manual cutting tool for hardened bolts?
« Reply #1 on: March 09, 2014, 04:33:59 PM »
I doubt they are hardened.. or at least they won't be very hard.

Not sure I understand the desire for a manual tool?.. A sawzall is a very useful tool indeed and as we all know good tools are worth their weight in gold.. So if that is the tool you need I'd go get one.

What I am not sure about though is when you ave cut the head off the bolt how will you then get the remainder of the thread out of the nut?

Typically I would heat the nut with oxy-acetylene then hit the bolt head with an impact wrench. In fact if you hit the bolt with a big impact wrench it will likely just twist the head off anyway, thus no need for the sawzall.

If you don't have oxy acetylene I'd spray WD 40 into the threads in the nuts for a few days and then get either the impact or a hand wrench on the bolt head. Try TIGHETENING the bolt ever so sligthly before un doing it. This often breaks enough of the rust loose to allow the bolt to be undone.

Frank

greaper007

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Re: Best manual cutting tool for hardened bolts?
« Reply #2 on: March 09, 2014, 09:22:59 PM »
I'm with frank, try some penetrating oil or heat before you cut them off.    I don't have access to OA, but I've had luck with a simple propane plumbing torch in the past.   PB blaster also seems to work well for stuck bolts.

If that doesn't work just buy a sawzall.   They're really an indispensable tool that you can use for tons of things.  They're also fairly cheap, so you can get a name brand one for less than $100.   Or you can buy one at harbor freight for like $20 with a coupon.   I bought one to cut the exhaust pipe on a car, and ended up using it almost everyday in a house remodel.   Great little tool.

kendallf

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Re: Best manual cutting tool for hardened bolts?
« Reply #3 on: March 10, 2014, 10:13:15 AM »
The torch also works great for getting the old bushings out (in flaming, smoking, burnt rubber smelling chunks!).   :-)  I was doing A-arm bushings on my daughter's Camry a couple of years ago, and the profile of the arm made it nearly impossible to press the old bushings out.  The torch took about 5 minutes, and I got to make Beavis and Butthead "heheheh!  Fire!  Fire!" noises.

BlueMR2

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Re: Best manual cutting tool for hardened bolts?
« Reply #4 on: March 10, 2014, 10:14:05 AM »
I doubt they are hardened.. or at least they won't be very hard.

Not sure I understand the desire for a manual tool?.. A sawzall is a very useful tool indeed and as we all know good tools are worth their weight in gold.. So if that is the tool you need I'd go get one.

What I am not sure about though is when you ave cut the head off the bolt how will you then get the remainder of the thread out of the nut?

Typically I would heat the nut with oxy-acetylene then hit the bolt head with an impact wrench. In fact if you hit the bolt with a big impact wrench it will likely just twist the head off anyway, thus no need for the sawzall.

If you don't have oxy acetylene I'd spray WD 40 into the threads in the nuts for a few days and then get either the impact or a hand wrench on the bolt head. Try TIGHETENING the bolt ever so sligthly before un doing it. This often breaks enough of the rust loose to allow the bolt to be undone.

I'm not a fan of power tools, I only use them as a last resort.  If it comes to that, I'll borrow one from a friend.  I wouldn't mind having a nice handsaw in a similar to sawzall blade size though, since I would use it a lot (right now I often just stick a hacksaw blade in my vicegrips for small jobs, this is not a small job though).

It's a hardened eccentric adjustment bolt that goes through a bushing (in an arm) and a double shear mount.  The bolt rusts to the inside of the arm.  If you cut through the bolt on the outer edges of the bushing (inside of the mount), the head will easily pop out of the mount.  The nut is already removed, those don't seize too bad.  Then, you can slide the arm down from inside the mount.  Other than side access for a saw blade and the tiny space to get at the head & nut, there's no room in there.  Can't get a hammer in there as the frame of the car is in the way.  The area that seizes is so deep (and long) that penetrating oil is ineffective.  It's a very common problem on Mitsubishis and this is the best practice repair.  :-)