Removing hardened 19mm bolt from cast iron L2800

[Stubbyie]

Regarding removal from hole of super-hard broken EZ-out...

Olde machinist tricke:

First heat the EZ-out cherry red with torch.

Quench in mercury till cool.

Use EZ-out as usual.

If stuck or broken, apply center punch centered on shank.

Whack with BFH as hard as you can.

EZ-out turns to dust.

Blow hole clean, start over.

Problem these days is finding mercury but well worth the effort.

Two things: process may now be overcome in large shops by using electrical discharge machining (some how-to on web claim can be home-built).

When dipping hot piece into mercury do so outdoors and stand upwind to stay out of vapors. Remember the term 'mad hatter' came from overexposure to mercury.

Same process may work using other material for quench, just don't know.

Interested if anyone can report first-hand experience using alternative.

 

[ShaunRH]

Depends on what the goal is of using Mercury. If it's an attempt to somehow 'harden' the surface casing of the EZ out then there are dozens of other methods. If it's to cool with maximum speed, ICE water with anti-freeze mixed in does a good job. That lowers the freezing temp and raises the boiling temp. Again, unless it's environmentally friendly anti-freeze, stay upwind please.

 

[Tooljunkie]

Smashing easy out works sometimes. Have done it with broken taps as well. Please wear a face shield and safety glasses. When it breaks, pieces go in every direction.will try antifreeze thing next time im hardening something. Used oil is an old school method too,also to be done in well ventilated area.

 

[kubotasam]

I've been there and done that with an easy out, once that breaks, it's not so easy! I do a lot of work on large fire pumps for fire sprinkler systems, typically with them everything rusts. One time I snapped two bolts holding the pump packing seals in so I went to the easy out. Snapped that off and I thought I was screwed. Tried every drill bit I had and the easy out would burn them right up. Finally, I went to the van and broke out a small Hilti hammer drill as my last option. I put that to the easy out with a carbide concrete bit and it ripped through the easy out like butter. .

OLdeEnglish-- You are my hero of the day!!!!! I just went through this not with a broken easy out but with a broken hex key. I had a slightly stripped set screw in the drive of my snow blower I am trying to restore. I foolishly tapped a slightly oversize metric hex key into the set screw. Well you know what happened. It snapped off flush with the surface. I knew I was in trouble. (Why did I not just drill out the set screw in the first place?) I tried to center punch the broken hex key. It just blunted the center punch. I tried a carbide grinder on a dremmel. No luck. I new I was in trouble.
Then I remember your post. Grabbed my SDS Hammer drill. Put in a 1/4" masonry bit. Can't say it went through like butter but it worked great. I don't think I would have ever thought of this method myself.
One again my hat is off to you.
Sam

 

[ShaunRH]

Oil quench vs. Ice/Antifreeze quench are two different treatments. Oil quench is to more slowly cool the surface of the metal. It makes the surface metals less brittle. Very useful for edged items: slightly harder edge, but flexible core metal.

Ice/Antifreeze is looking for a faster cooled, harder surface. It's a deeper hardening and is more brittle. Useful for very sharp edged devices that won't be exposed to a lot of torsion or tension stress.

A blacksmith hobbyist friend of mine would remind us that all quenching is mostly a surface treatment and it all depends on how you heat the metal and to what level will determine the final result. Metal treating is something of a black art that uses scientific principles.

 

[meanjean]

I use ATF and acetone in a 50/50 mix and put it in a large syringe I use for cattle. Put drops exactly where you need them. Works excellent.

Do you have a problem with rusty cattle?

 

[FTG-05]

Do you have a problem with rusty cattle?

Sounds to me he has a squeaky cattle problem.

 

[coachgeo]

Sounds to me he has a squeaky cattle problem.

Well actually sounds like his cattle is no longer squeaky. But don't get why he wants them to get "loose"?