Harry Marinakis

A2 for a hammer eye drift?

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Made my first 2-1/2 lb. rounding hammer with borrowed tools, now I am looking to make some chisels and drifts for myself.

The steel I have lying around my shop include 4140, O1, W1, A36, A2, rebar, and some truck coil springs, leaf springs, and axles. I can also get jack hammer bits.

I'm thinking the A2 is a good steel for making a hammer eye drift. Am I correct?

 

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Okay, help me understand

I was thinking since the A2 can be air hardened, it doesn't matter how hot it gets while drifting, I can just quench it and keep drifting, and then let it air cool when I'm done.

No?

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35 minutes ago, Harry Marinakis said:

The steel I have lying around my shop include 4140, O1, W1, A36, A2, rebar, and some truck coil springs, leaf springs, and axles. I can also get jack hammer bit

What do you do, that you got all the steel laying around?

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6 minutes ago, Gerald Boggs said:

What do you do, that you got all the steel laying around?

Pretending I'm a blacksmith. :) It's just a hobby, trying all kinds steels and projects. I like to make my own woodworking tools.

I'm trying to understand the reasoning behind using this or that steel for this or that purpose.

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Good Morning Harry,

"I'm trying to understand the reasoning behind using this or that steel for this or that purpose."

This is the $64,000.00 question. Some people ask that question and end up working their whole lives, trying to confirm the answer. Metalurgist's, Chemist's, Mechanical Engineer's, Blacksmith's, etc.........  You can get some answers in 'The Machinery Handbook', they have a page on typical uses for different Steels. You have to remember that it changes with every person and application. One person will try something and can't get it to work, another uses the same product everyday for the same application.

The real answer is, "What do you have available to you? What do you have to get the job done?". There is a difference in whether you are making the Tool for occasional use or daily production Industrial use. For your own use, you use what is on the rack or in your ????????? pile. For occasional use, you can use mild steel for a drift. Some people get caught up in the Glitter of using this or that Alloy. They use it once and they are bound and determined that, that is the only way.

Don't be afraid to experiment, but........., BE SAFE!!!

Neil

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it is time to read up in why there are different steels, there is a lot more to it than just how it hardens, also working air hardening steels is a different animal as well, ask  what happens to A2 when its hit with a hammer at the wrong temperature, the answer may surprise you

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42 minutes ago, Harry Marinakis said:

I can just quench it

This may turn out to be the critical issue as well.  A lot of air cooled steels don't react well to water quenches to cool them off if the drift happens to get stuck in the hammer head billet, or just gets used too long.  I'm not familiar with A2.  I've used 4140 and been happy with that.  I just made one out of H13, and will have to remember to be extra careful not to quench it if it takes on any color at all.

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OK a little gedanken experiment on differing properties:  Why not just use a hunk of glass?  It's hard and I'm sure that hamming on it won't cause problems because it's hard!

You may run across folks  who dislike medium carbon steel tongs due to the overheat-quench-break issue and others who like them because they are lighter and so manage them to not overheat them or just cool them in air. (To split the difference I've forged a Titanium set of tongs...)

If you really want a high end drift look into the S series alloys (and NO,  jackhammer bits are seldomly made from S series steel no matter what some junkyard steel list has on it!)

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The problem with A2 is just that, it is an air hardening tool steel. That alloy can get extremely hard and extremely brittle.  4140 on the other hand is a "tough" alloy that can take a lot more impact than A2 will. Save the A2 , O1, W1 for cutting tools, and use the others for punches and drifts. As mentioned above the use and usage of said tool will determine what you use.  One time use? The A36 could work.  Need to make 30 parts? Better to use the 4140 as it will hold up better with heat treating. For chisles you may want to look at something like 5160 (coil springs can be a good source - but unless you get new stock to verify the alloy  it will always be a mystery metal).

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Thanks all

I can read all day about A2 but the reality is  that nothing that I've read about A2 specifically addressed my questions.

I've been using mostly junkyard steel for my projects (I like coil springs), and have made woodworking chisels, gouges, irons for hand planes, hot cutoffs, steel chisels, hold fasts, knives. But I've started buying known steels recently.

Here is one of my 16-inch junkyard coil spring knives with an octagonal briar burl grip, a reproduction of an actual medieval knife in a museum collection.

I bought some 4140 to make hammer heads, guess I'll use it for other things, too.

imgp6550_162.jpg

imgp6557_966.jpg

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Depending on the jackhammer bit they can make awesome drifts. Not sure of the manufacturer but I was given a couple by the home depot rental counter. I can water quench them at red heat and got right back to pounding on it. Be sure to test yours before doing any heavy hammering right after a water quench. 

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We had a member here whose career was resharpening jackhammer bits and at over a million done he said only a few were anything but 1050 due to cost considerations.

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Steve, I went back and re-read my books on steel and smithing -- then I realized that you are the author of my favorite book!

On 4/6/2018 at 6:21 PM, ThomasPowers said:

Do you remember the cite on that one?  I'd like to look it up.

It's in a private collection now. I spoke at length with the owner. I've made reproductions of a few of his knives: site

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On 4/7/2018 at 4:30 AM, ThomasPowers said:

over a million done

That sounds terribly boring. Over a 40 year career, assuming an eight hour working day, that's approximately one every five minutes non stop. 

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Set up right it is a fair bit less than 5 minutes to re point a breaker bit.

Grant, the person Thomas is referring to did have a number of employees as well.

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Everyone forgot to mention the dangers of striking a piece of steel that is as hard as A2. A chunk of steel could break off and shoot into your leg hitting your femoral artery...you could bleed to death in mere seconds.

It was hinted at

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It might have been hinted at but never explained why! Some people might not take that into account. I didnt mean to offend anyone!!!

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Having worked on an assembly line before; boring is just part of the job. I'm not too fussy when it comes to feeding a wife and kids! Even as a software engineer I had tasks like comparing character by character the 16 page  output of a command with what was printed in the manuals. (Old days---now I would just diff the files!  Had to explain to a manager of a different group  recently that we did not review a set of 40,000 line files line by line to see if they were correct. We diff them and look at the mismatches and if the file we are provided to check against is bad then GIGO.  Though I do check that recent changes got into them)

Yes I miss Grant and his descriptions of his work  processes and viewpoints.

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The more i think about this the more it bothers me.  I dont understand why it was necessary to edit my post.  I didnt do anything wrong i was just trying to be helpful. Why not post your own comment?  I think this is enough to make me go back to being a lurker instead of a member.  I think i will stay over at Don Foggs forum!

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