thingmaker3

I would ike to know who posed this question.

This person: http://www.iforgeiron.com/user/7946-jason-m/

I'm betting it's an honest inquiry by someone wanting to learn.

The monetary value of a drawing or blueprint depends on what it is, who made it, how easy it is to read, how accurate it is, how complete it is, and whether I want it. :P

Feh. REAL manliness is using one's BARE FIST to pound the glowing iron!

I witnessed a similar demo at the 2006 ABANA conference in Seattle. It is impressive see the metal moving under a jackhammer, as well as to see the smith manipulating the jackhammer about the work.

And those Finlanders do nice work indeed!

I think a lot of these folk are holding out for some of P.T. Barnum's one-born-every-minute types. I think other of these folk are said types themselves.

Knife-making can get the hands permanantly dirty. If you plan to be a surgeon, grubbing around inside human bodies, you might start wearing gloves when knife-making. Of course there are more specialties in medicine than I can even guess at.

For steel, there are plenty of good tools thrown away every day. Check local cabinet shops for larger cast-off saw blades or planar blades. Check auto shops for dead leaf springs. Find someone who makes custom fishing rods - they throw away perfectly good A-2 steel big enough to make small knives.

Don't ignore the steels you can't heat-treat yourself. Shipping blades off for heat treat can be quite affordable.

And please DO post pictures if you use a 420J scalpel you made! :)

780C would be hot enough only if the steel were heated very very slowly.

It is important to remember the phase diagram is isothermal. If we heat more quickly, the transformtion temperature increases. Eutectioid transformation temperature can be around 1600F when induction heating small sections.

I echo Son_Of_Bluegrass' suggestion. You might get away with as little as 800C.

How 'bout a cool grand for an old rusty rivet forge? http://portland.craigslist.org/clc/grd/1884237208.html Fellow says "You will not likely see another this old very often." I see them about twice per month on the local Craigslist, so I guess twice a month is not very often. :lol:

The full equation requires at least four axis, Mr. P. We have to account for initial carbon concentrations, and the presence of things like nickel or silicon.

Is there any graph in particular you are referring to? Do you know one for diffusion into steel?

What I had in mind was something like I have in a couple of my books: set of graphs showing carbon content x millimeters below surface after y hours at z heat for a specific steel of uniform size.

I can dig out some titles later in the week if you wish... might find them in your local university library...

because lets face it, apartment life is far cheaper.

I suggest you do the math again, making sure to compare dwellings of similar square foot size. You might also look into renting a duplex..

Rate of carbon diffusion in steel is proportional to the square of the Kelvin temperature. Translation: pack carburization would take days & days at dull heats, hours & hours at medium heats, and a few hours at brighter heats.

Note also: the "case" is not just a well-defined layer where the carbon content drops off at the edge like some underwater cliff. There is a gradient.

Try an internet search on "Ficke's Second Law of Diffusion." Don't get bogged down in the math examples, but do study the graphs.

These charts were universal commercial specifications for tongs that were on sale to the general trade so that when they were purchased the customer knew what they were getting, or if you were going to produce them commercially, this was the standard expected.

Thank you, John. That makes a whole lot more sense.

Tongs need to fit properly to secure the workpiece, that is why sizes (diameter, square or height and width) are specified.

Mass as I understand it is the total volume/weight of an item, not relating to its linear dimensions (ie, width, breadth, length)

What do you understand as to the meaning or definition of "mass" ?

I define mass the same as they taught in high-school: height x width x lenght x density. But why do I need longer reigns for a larger diameter piece? I could understand more stout reigns for a heavier piece.

For example, if I'm handling a 2" diameter by 5" long pipe versus a 3/4" diameter 5" bar, why do I need beefier tongs for the tube? Why can I get away with 15" reigns holding a knife blank flat, but have to switch to 22" when dressing the profile?

How come the overall mass of the workpiece has less influence on the size of tong than a single dimension of said workpiece's cross-section?

Am I thinking about this backward?

It is a mild steel, with only 26 points of carbon. It has 75 points of manganese which is also not a problem, as far as forge welding.

Chemical composition of A36 depends on thickness. Carbon ranges from 25 points if less than 20mm to 29 points for 100mm or thicker. Manganese is not specified for stock of less than 20mm, and can be between 0.8% and 1.2% for stock thicker than 20mm. Some manufacturers put in a bit of copper.

But, yes, it can indeed be forge-welded.

Heck, I'd be happy to find a commercial mix that doesn't crumble! I cope by sprinkling fine sand in the cracks prior to lighting. It fuses in and eventually the cracking slows down.

Here is a link that will help you the size of the tongs should be made in relation to the size of stock you are working with. For twist I use a pipe wench with the teeth ground off and a bar welded to the head the jaws are adjustable and the frame is strong. http://www.anvilfire.com/bookrev/ind_pres/tongs_chart.htm

I've seen that Machinery's chart (or variants thereof) a few times. What I don't understand is why the chart goes by diameter or side length of the stock instead of by mass of the stock. Can someone explain the theory at work here?

A lot of industrial supply houses and woodworking suplly stores sell 1/2" belts in different lengths and grits.

For plain-carbon and low-alloy hypoeutectoid steels (stuff like 1060 or 4140), the transition temperature is about 50F above the Curie point. For hypereutectoid steels and high alloy steels (like 1095, or CPM9V), all bets are off.

What a marvelous oppertunity! I hope you skewered that thing & fried it up with some hush-puppies and slaw!!

Adam, remember that Harcourt was writing about the bursting of wrought iron, not mild steel. Wrought iron has up to a quarter million ferrous silicate stringers per square inch of cross section. Mild steel does not.

Many of the books from the late 19th and early 20th centuries deal with proper technique to avoid similar phenomenon in wroght iron. You-tube videos deal primarily with our modern homogenous steels.

Passivate?

Clean it really good & soak it in citric acid.

Since these steels are being hyped as good for grouser parts, they might make really good picks or shovels or grub hoes.

Hey Sam! Thanks for starting this thread. All these interesting replies have talked me into getting some more of these spiffy locking pliers! After browsing through some of the locking plier patents at the USPTO website, I might even try to make some of my own. Never could've happened without ye, Sam! :lol:

do you know where I can find information about it?

http://www.postdiluvian.org/~mason/materials/aisi_sae_steel_compositions.html

The C80W2 looks like an exciting steel to experiment with.

Sorry no I was going to try it but then I got my hand on some Parks AAA.

Dude! Where?

Why does everybody make this statement everywhere these days?!?

I am speculating: The confusion might be due to average carbon contents. Average of both types of steel in the nihonjin blades is about 0.50%. Most folk think 1050 is 0.50% carbon as well, even though it can be as low as 0.48 or a shigh as 0.55%. I don't know for sure why the confusion exists, but this might be one reason.

1069 might be a better choice for hammon, due to a bit less Mn.