Case hardening

[Jan-Eric Nystrom]

Anybody here with CH experience?

I've just machined the links for my 4-6-0, and am planning to case harden them. I bought a special CH powder, containing carbon, sodium carbonate and molasses (!) for the purpose, and am using ordinary cold-rolled steel for the links - they will survive for years w/o hardening, but I thought it might be fun to try...

A pottery artist who has her electric kiln in the same building as my workshop has volunteered to heat a "package" I provide to either 960 or 1020 degrees C. Is this OK?

Any other hints?

Adthanksvance,
J-E

[This message has been edited by Jan-Eric Nystrom (edited 02-10-2006).]

[watt-steam]

Hi JE,

Ive used the powders, but only by direct heating the part to red hot, dipping in powders, and heating up again to red hot. I do this a couple times, depending on depth of case needed.

Is the temperature you mentined in centigrade red hot for steel? I guess if it is, then you're OK.

[Jan-Eric Nystrom]

<font face="Verdana, Arial" size="2">Is the temperature you mentined in centigrade red hot for steel?</font>

Yes. It's "bright cherry" or "cooked carrot", whatever is your favorite dish...

BTW:
9/5 Centigrade + 32 = Fahrenheit
and
5/9 Fahrenheit - 32 = Centigrade
(just so you know... ;D)

Greetings,
J-E

[Bill Shields]

J-E:

If your stuff is like our Kasenit, then you are on the right track...although I am fairly sure our stuff doesn't have molassas in it...

Many of us have been using this stuff for years with great success.

The Kasenit we use here contains sodium ferrocyanide. They SPECIFICALLY say use it OUTDOORS because it may cause 'irritation'.

I did my Hudson links in it 25 years ago, and the links are like new...the pins are worn, but they are easy to replace...

Bill

[Jan-Eric Nystrom]

<font face="Verdana, Arial" size="2">
I did my Hudson links in it 25 years ago, and the links are like new...the pins are worn, but they are easy to replace...
</font>

Are your links case hardened?

I've used ferrocyanide in photography. It's not poisonous like the non-ferro cyanide, which is deadly, as you know...

J-E

[This message has been edited by Jan-Eric Nystrom (edited 02-10-2006).]

[Bill Shields]

yes, links hardened with Kasenit...sorry...

I don't like using anything with cyanide in it anywhere near breathing beings, 'safe' or not...

[fred v]

i also use Kasenit for the links and link block and have run the fool out of the engine for 10 years with little or no wear.

i heard that you can heat the parts and dump them in laytex paint to C.H. anyone heard of that before?
fred v

[ErieAtlantic7597]

JE,

A year and a half ago, I removed the main crank pins from my Atlantic after years of hard use. I made a puller to accomplish this without removeing the wheel set. My friend
Peter Bialeki made two new crank pins, then we hardened them with the Kasenit method.
Heating to past cherry red, rolling them around in the powder, them reheating to past cherry red again, then, according to directions, plunged the pins, red hot into cold, clean water. Our water here in SW Florida is never really that cold though.
Anyhow, after a year and a half of running for many hours, there is not even a mark on those pins. Its one of the best things I've done service wise on the engine.

Take care,

Bruce

[Jan-Eric Nystrom]

Yup, hardening the pins is a good idea - I used drill rod (called "silver steel" in Europe) for my pins, which is a very easy material to harden and temper.

But the links are water-jet cut from ordinary, low-carbon cold rolled steel, so I thought I might try case hardening. I've given a surplus piece to the potterer (or is it spelled potter? Well, not Harry, anyway... ;-) and we'll see what happens.

She can't quench them - if she opens the kiln red-hot, all her pots will crack - so I'll have to re-heat and quench myself.

It will be interesting, and I'll inform you what happens.

Greetings,
J-E

[Bill Shields]

J-E:

You might not need a kiln....with a bit of practice, a torch works just fine...

Typically folks will put a sheet of steel between the torch and the part and heat the sheet to get the part hot...try it on some scrap...might save Harry the potter's kiln...

I have, in a pinch, heated parts over a gas fired outdoor BBQ using this method....

One thing still puzzles me...what flavor molassas is used?

[This message has been edited by Bill Shields (edited 02-10-2006).]

[ErieAtlantic7597]

JE,

Thanks for the quick return post. I just remembered something that I learned from my Grandfather who was a file hardener for over sixty years. BTW, he retired at seventy four, and passed away when I was twenty three. He was my buddy from when I was a kid right up untill he passed on.
I recall him saying that quenching could be done with oil, water, of course, brine water, and soluable oil and water. To change the characteristics of the hardened steel.
And in some cases, anealing was needed also.
Wow, here I am in mid sixtys now and I'm quoting my Grandfather. Where does the time go.
Hope some of this helps.

Take care,
Bruce

[Bill Shields]

CAREFUL on quenching....for those of you that don't know....

Different steels quench in different liquids..oil, water, air, brine etc: cannot always be used interchangibly (sp?) from one steel to the other...it has to do with the rate of cooling.

I don't quote my father, but every once in a while, I will say something, stop and think for a second, and realize that I AM my father...a truly frightening thought.

[Unka Jesse]

About heating Kasnit with a torch. It will work but do not use a "hard" flame from an oxy/acet torch. Leave a bit of feather in the flame to soften it. Propane torches work fine and I used to use a common gasoline blow torch in a little oven like thingie to heat my gun parts for case hardening with Kasnit. I did harden some parts by sealing them in a piece of pipe filled with leather scraps. That worked well too and even gave a bit of color to the parts.

Unka Jesse

[ErieAtlantic7597]

Jesse,

Right you are. Me being in the refrigeration business for forty five years now, I used my turbo torch with a number eight tip. That worked just fine. Not too harsh a flame. But plenty hot enough to get the steel to the color that I was looking for.

Take care,

Bruce

[ErieAtlantic7597]

Bill, First of all, I do believe you miss read my post on the hardening thing. I, in no way suggested, recommended, or advised anyone how to quench material. I KNOW that I don't have that kind of expertise. I'm not a BSer, so I certainly would not issue that kind of information.
As far ar my sainted Grandfather goes, he worked for and was the hardening shop foreman for a company even you will recognize. Nicolson File Co. Then from the war years till he retired in 1964, he worked for the Carson Newton Co. If anyone has an old file with an alligator on the tang, good possibility that my Grandfather had something to do with its heat treating.
At this stage of my life, I WISH I was more like him. He was a REAL gentleman and a REAL CRAFTSMAN.
And happily, I am like my Father. He was a professional automobile mechanic for over fifty years. And I've been a refrigeration and appliance mechanic for just short of forty five years myself.
Actually, now I'm a technical trainer.
Bill, different than you, I'm glad that I'm somewhat like my Grandfather and I'm certainly like my Father in as much as mechanical abilities go.

Bruce

[Jan-Eric Nystrom]

So, you're saying that for carburizing, I don't need to heat as high as when hardening? Is a BBQ or the glowing coals in a fireplace hot enough?

Of course, for hardening, you gotta heat over the austenizing temperature (I have nice propane torches that will do that), but not for carbon to diffuse ionto the steel?

The instructions with the CH powder says heat to 900-1000 C (1650 - 1800 F)...

(I don't know the type, taste or flavor of the molasses in it - but it's not much, I guess it's there for making the powder adhere to the red-hot iron. ;-)

Greetings,
J-E

[Bill Shields]

Bruce:

Sorry..was not taking shots at anyone, but since this post was about heat treating, I believed that there was the possibility of someone mis-understanding what you were saying. You and I know the difference, but there are probably folks out there that don't and I just wanted to clarify that there are differences.

J-E:

Like Bruce says, a torch is enough to do it right as long as you heat evenly..takes a bit of practice is all.

B

[This message has been edited by Bill Shields (edited 02-11-2006).]

[fred v]

i'm using O1 drill rod for my crosshead wrist pins, what do you guys say about hardining and temporing them?
fred v

[Bill Shields]

Fred:

For my wrist pins, I fix it so that the pin will not move in the crosshead, and use Nylatron for the bearing...and forget it for what I assume will be the the life of the loco (I will let you know when I get a failure or the loco dies).

[Jan-Eric Nystrom]

OK, fellows, I've tried the "carbon/soda/molasses" powder... The potter heated the package in her oven, and I then tried to harden it.

No success, no hard surface even though I heated to carrot color, and dunked quickly in water. I've also tried heating, dipping in powder, heating. Repeated 4 times before quenching.

Maybe my base steel (type Fe52 or S355 in Europe, i.e. "structural steel") is not suitable for case hardening? Or do I need to quench from an even higher temperature?

Any ideas?

Greetings,
J-E

[Bill Shields]

j-e:

i see that S355 can be .35% carbon content...is that correct?

my german is a bit rusty, and the only chart i could find came from thyssen.

IF this stuff is like 1030, then you can harden by:

Heat to 1500-1600F, water quench....

[watt-steam]

Fred-

For O-1 or drill rod, heat to bright red heat, quench in oil. Couldn't be any simpler. Don't use motor oil, it;s full of all kinds of stuff not suitable for hardening steel. Corn oil or machine/mineral oil are fine.

To temper the pins, heat them gently to a straw or light gold colour, quench again in oil. To see the colour better, polish or sand the parts to a bright silver finish before tempering.

If you do the above they'll be hard as L but tough.

If the pins or your other 0-1 parts are very small you can put them on a steel plate for tempering and heat it from below, then dump the parts off the plate into the oil. This helps keep you from overheating the small parts.

For case hardening, Kasenit or Quick Hard powders can be used on all low carbon steels. Just heat the part to red, dip in the powders,roll on a steel plate to embed the powders, reheat coated part to red, quench in water. Repeat 3 times.

I haven't tried it on what I would call structural steel, but I know there are MANY kinds of structural steel for different loads and different regional temperatures. Best thing would be to try a few test pieces of what you have. The powders are easy to use and not real expensive, because you don;t use much each time, so there's no big fuss to try it a few times.

[Unka Jesse]

The first I ever knew of Kasenit was when a salesman demonstrated it to my father at the GM&O railroad back around 1950. He took a common railroad spike and hardened the tip to make a cold chisel out of it. Worked very well on what must have been a pretty low grade of iron/steel. J-E, possibly you are not getting the parts hot enough before quenching them?? The stuff has always worked for me, even on 12L15 leaded free machining steel.

Unka Jesse

[Jan-Eric Nystrom]

One thing to consider:

The powder is NOT Kasenit, it's something sold by Chronos in the UK. It has no ferricyanide in it, just carbon, soda and molasses (the latter to malke it stick to the heated iron?)

I'll try heating to a higher temp, but it's not very easy to get the entire link orange-hot with my burner:

http://www.saunalahti.fi/~animato/temp/CH.JPG

Maybe I need an even bigger burner?

Greetings.
J-E

[watt-steam]

J-E,

That expansion link looks plenty hot to me for case hardening. If you can find some Kasenit, Quick Hard, or your local kind of case hardening powders, and there's not somthing strange about your type of steel, it should work fine at this heat.

You might ask your local welding supply store for case hardening powders, they usually have them.

Maybe there's something not right with the Chronos powders chemistry?

[Phill Smith]

Gents,

I thought I'd through in my 2 cents worth here.

I used gauge plate for my curved links, as it hardens nicely.
For pins I tend to use K455 (tool steel), and then use casenite on it for that extra hardness.... A bit of over kill, but I've never had to replace one. I have had to replace a couple of phos’ bronze bushes, but that was due to dirt inclusion from derailing.
I use K455 rather than silver steel, because it's far stronger and nowhere near the brittleness. Therefore it is excellent for threaded pins. Plus, I used to get as much as I wanted for FREE!!!!! An important factor. If I was buying the stuff.... I would be buying K190 simply for it's superior wear resistance, hardenability (I wouldn't need the casenite), and dimensional stability during hardening.

I know of quite a few people who are making their curved links from mild steel and are then sending them off for nitriding. I have seen one curved link that was done this way with a failure in the casing, but that was due to the soft mild steel compressing under the casing. I don't know how it happened, but someone, somewhere/somehow, did something REALLY stupid. All the others appear to be great, with no discernable wear.

I also made my wrist pin (cross head pin) from K455, without heat treatment. It has no measurable wear after 17 years, and 10000 km, of hard work. They still have a beautiful polish and only a couple of marks.

Cheers,

Phill.

[Jan-Eric Nystrom]

Since the link is water-jet cut together with a bunch of other parts for the tenwheeler (rods, axle boxes, hornblocks etc.), I didn't have much choice in material, so structural steel it is. I tried to case harden a bolt head with the Chronos powder, but no success - so maybe the powder isn't good?

Or is the case usually so thin that you can't notice any difference when comparing hardened to unhardened using a needle file?

Greetings,
J-E

[tel]

A needle file should skate off it like glass J-E - should be glass-hard, in fact. I use 'Hardite' powder which, (depite rumours to the contrary) has nothing to do with a certain medical product, it is, rather, the nearest thing to Kasenite that I could find.

[Bill Shields]

J-E:

I design my links, send them to my brother in law who cuts them from hardened stock on his wire machine.

A LOT less hassel...

Your picture of the torch looks AWFUL hot to me....

[Unka Jesse]

J-E, it is a sure bet that the stuff you are using is at fault. That link, as hot as it is, would be plenty hard after two or three soakings with Kasenit. Try to locate something better, much better, than what you are using. It is kind of hard to see the colour of the parts with Kasenit because it causes the flame to be bright yellow, but you can get perfect results with it.

I have almost a pint of Kasenit and could spare you some if you cannot get it in Finland. I don't know what problems we might get into trying to get through customs though.

Unka Jesse

[Jan-Eric Nystrom]

<font face="Verdana, Arial" size="2">1 - It is kind of hard to see the colour of the parts with Kasenit because it causes the flame to be bright yellow, but you can get perfect results with it.

2 - I have almost a pint of Kasenit and could spare you some if you cannot get it in Finland. I don't know what problems we might get into trying to get through customs though.
</font>

1 - same here, the sodium carbonate in the Chronos powder colors the flame strongly.

2 - thanks for the offer, but I don't think it is all that necessary to harden my links - I won't run 7/27/365 anyway... http://bbs.livesteam.net//biggrin.gif

(The unhardened links in the "Chicken" show no wear whatsoever after two years.)

Yes, any powder in the mail is suspicious nowadays. I remember a visit to the Disney Studio back in the early 1980s, when I was given a small amount of white xerox toner (for my animation work), I wondered what the customs would think. Fortunately, my luggage wasn't checked that time. How would you explain a jar of white powder to customs, today?

But, back to Kasenit - from what I understand its carbon dust and sodium ferro- (or ferri-) cyanide? Does anybody have better info about the ingredients or proportions? I could mix my own - there shouldn't be any problem getting the chemicals. The ferro(i)cyanides are NOT deadly poison...

Greetings,
J-E

[Bill Shields]

J-E:

the can I have lists the contents, not the mixture thereof....proprietary secret I would guess.

Do you want to harden only the stephenson links or a lot of other stuff?

[Jan-Eric Nystrom]

<font face="Verdana, Arial" size="2">Do you want to harden only the stephenson links or a lot of other stuff?</font>

Walschaerts, not Stephenson... yes, that's what I intend(ed) to do. All other parts needing to be hardened will be made of drill rod or gauge plate, so no problems there.

Greetings,
J-E

[Bill Shields]

J-E:

Sorry, been doing a lot of Stephenson work and my brain is mush...

If you really want hard links and cannot get it worked out, send me a drawing for the link and the slider inside...

I can ship that easier than I can ship Kasenit.

[Jan-Eric Nystrom]

I'm wondering if hardening is really necessary? Also, I do have a spare pair of water-jet-cut links if the first ones ever wear out.

In fact, after noticing some wear, the first thing I'd do would be to "freshen up" the link slot and make new, slightly larger bronze dies - not a very big job...

Greetings,
J-E



[This message has been edited by Jan-Eric Nystrom (edited 03-01-2006).]

[Bill Shields]

I do all mine from hardened tool steel, cut with a wire...forget about it for life.

can do a set for you if you like and are not in a big hurry....

[Unka Jesse]

The Stephenson links for my RRSC American are made of tool steel, but not hardened. I don't know how long they will last, but because I rarely get to operate any of my locomotives other than the Newbie and Falk, I expect they will outlast me.

I think it is discrimitory of you people over in Europe and Great Britain to have so many club tracks you can run on. All I have is my pitiful little 40 foot circle of track in my front yard or a 3-1/2 hour drive to the track in Nashville. I haven't level space larger than that unless I build some long low bridges. Auntie Fern might get hostile if I started doing earth work in the yard to get a level place. http://bbs.livesteam.net//biggrin.gif

[Jan-Eric Nystrom]

Then you just gotta do what Walt Disney did - build a tunnel under the flower beds... http://bbs.livesteam.net//biggrin.gif

Greetings,
J-E

[pockets]

Or what they do in Florida when they discover that the pasture they bought is only under water for 6 months out of every year.....TRESTLES.. Jesse, I had you pegged for a country boy. LOL

Best regards,
Greg B.

[Unka Jesse]

'Twould be a pretty tall/steep trestle since the back yard is 8 feet lower than the front. Maybe I could put in one of those incline railways to get up and down the slope. Just add some cog wheels in the centre of the drive axles and away I could go. Have to make them retractable though as there is not enough room to make the cogs as large as the drivers, especially on the American. I suppose I could speed up the cogs till their circumference speed would match that of the drive wheel tires. Roller chain would make a good rack gear I suppose.

Unka Jesse

[pockets]

Jesse,
You have cast the remnants of my mind assunder...........I need sleep....or Bourbon.....

Greg B.

[pockets]

Jesse,
You have cast the remnants of my mind assunder.....I need sleep....,or bourbon...

Greg B.

Ignore this...and I repeat.......

[This message has been edited by pockets (edited 03-07-2006).]

[El_Wet]

I am brand new to this place, so apologies in advance if this information has been posted in the past.

Years ago, all we had was Kasenit to make quick blacksmithing tools. It did not hold up well to the abuse from blacksmiths. (The physical and verbal types of abuse.)

Along came SUPER QUENCH and saved the day. (You have to say SUPER QUENCH, like you are saying SUPER MAN!)

Guys (and a few gals) have used this to make some pretty impressive tools. Repairs to tractor parts have been done with this stuff. But, don't know if anyone has used it for links, etc.

I personally tested the Rockwell hardness on a piece of 5/8 diameter 1020 mild and A36 structural (garbage, crud, junk, crap, a used Honda, dishwasher pieces and what-not ingredients) steel. Both showed through hardening on the cross section at 41 on the 1020 and 38-43 on the junk, garbage (deleted insult) A36 junk metal. (In case it doesn't show, A36 is just barely a metal and pretty poor at that. It is dispicable stuff.)

Just for fun, I tried SUPER QUENCH on rotten iron (real wrought iron from a 1890 bridge) test chisel. The rotten iron got hard enough to make 2 cuts before delaminating. Now that was impressive! But, I always suspected there was still a little carbon left in the rotten iron.

Considering the abuse blacksmith tools go through, there does not seem to be any problem with cracking from the through hardening.

Caution: SUPER QUENCH is not for high carbon or high alloy steel. I tried it on 4140. 4140 lost all toughness and shattered like glass. Tempering just brought the 4140 back to original condition.

Another great thing about SUPER QUENCH is that is really cheap. Especially, when I swiped a whole bunch of the ingredients out of the pantry and the wife never noticed the pilfering. It didn't cost a dime....wait...she doesn't work, so who paid for it? Hmmmmm.....I don't like where this logic is leading.

Once again proving that El_Wet is your primary source of ALL WET opinions and appropriate for the topic of SUPER QUENCH.

Follow the links for the recipe and details:

http://www.lametalsmiths.org/news/robb_gunter.htm

http://www.cvbg.org/tips/superquench.PDF

http://www.anvilfire.com/FAQs/quenchants.htm

[Bill Shields]

J-E:

Here is how I do hardened links - get my brother in law to wire them out of hardened tool steel. 1/8" thick with 1/8 holes for reference...for the Tom Thumb project.

http://www.netgazers.net/~shields/photos/TTlinks.jpg


[This message has been edited by Bill Shields (edited 03-08-2006).]

[Jan-Eric Nystrom]

Nice!

One thing, though: My links have two threaded holes for attachment to the link holder - how would you do those with pre-hardened steel?

BTW, That SuperQuench sounds interesting - now I just need to find the Finnish equivalents of those two branded products...

Greetings,
J-E

[pockets]

Bill,
Your b-i-l does nice programming. I envy you such relatives.

Greg B.

[willy]

Bill, perhaps you should leave this project to the brother in law as he has done the welding on the boiler http://bbs.livesteam.net//biggrin.gif

[pockets]

OUCH! http://bbs.livesteam.net//wink.gif

Greg B.

[Bill Shields]

Willy:

Different brothers in law...one is my wife's brother (weldor), other is married to kid sister (tool-die shop owner).

Actually 2 different projects going at once..the Tom Thumb with Jim and my 2-8-0. Jim is virtually blind from glaucoma, so I am pushing very hard to get things done using any available resources to speed things up....which includes letting my own project slip. By late this year, he probably won't be able to see to run the loco safely..so it HAS to get done now or never.

When it comes to boilers and safety, I have little room for compromise. My 'hand' is 30 years out of practice, and while I CAN do some of the welding, Roy is doing a lot of it where something more than simple downhill is called for. I am just too busy to spend hours getting my hand back to where I would trust it for all the rod burning needed to build this tea kettle.

I am many years past being too proud to get help where it is needed. One thing that my father taught me...a good engineer doesn't always try to do everything himself..he uses available, efficient resources to get the job done safely and quickly.

For the links:

I do the programming...I actually created the software system he uses..that is how we met 19 years ago.

J-E:

Threaded holes are not a problem. With this type of linkage, the 'shifting' arm is connected to one end of the link with a through pin...using typical marine engine practice of positioning from the end rather than the center of the link.

For my 2-8-0 linkage, which is as per your thoughts, I just threaded the holes before it was hardened / wired. Works well.


[This message has been edited by Bill Shields (edited 03-09-2006).]