Forge welding rail road spikes to make longer knives?

[Saakee]

Anyone here been messing around with forge welding rail road spikes to make longer knives/swords or know someone that is? I was recently thinking about trying my hand at making a bayonet out of one once I return from an apprenticeship (not for metalworking, a farming apprenticeship) I'm trying to get.

I know they're not great blades but since they're such a cheap resource, I figured I could work on a crap load of them and only have wasted time and fuel resources and not a lot of cash if I can't get the hang of working metal.

 

[zhyla]

I'd be concerned with the carbon content of the spike. A quick googling turns up ASTM A65, which specifies the carbon content for railroad spikes (in the U.S.). There is a low-carbon option, which is probably not what you want for forging a bayonet.

But sounds like a great way to get the hang of things.

 

[Saakee]

there're two types of spikes from what i've read, the normal ones and ones with H or HC [supposedly] on their tops used in corners and turns or something that have 40-60 points of carbon[not exactly sure what that means actually]. They've got a higher carbon content and grinding them will produce an orange spar.
I don't expect it to be a good bayonet, not something I'd trust my life with, just a show piece kinda thing for a wall hanger rifle. It also may end up just being research for a character in a story instead of an actual event for me.

 

[docnyt]

I've seen them at a local gun show but didn't handle them.

 

[hso]

They don't make good knives, just interesting ones.

 

[Brian Williams]

Go to a Spring shop, or a junk yard and get some leaf or coil springs, that will give you some decent stuf to work with.

 

[Tirod]

Be careful of what you're comparing to: Bayonets aren't very special, just medium carbon steel spring tempered softer, in the lower 50's on the Rockwell C scale. They are poor knives to begin with, as they are made to resist shock, levering, bending, and must have high ductility.

The average cheap $20 folding knife has higher carbon steel, and a shape and grind that promote cutting.

Nothing wrong with the better grade rail spikes as a source. The "forging" process is really a matter of beating hot steel into a more useful shape, and it's an efficient way for a low tech shop to do that, as many third world metalsmiths attest. But, it won't make as good a knife as a piece of 52100 bearing race, lawn mower blade, or the legendary Studebaker leaf spring. Those will be a lot easier, too - hammering is hard work, and workmen look to simplify their labor any way they can.

Look around for the large unit bearings from 4WD or front drive cars. Those are a much better grade of steel, cheap enough when free, and plenty of challenge forging. Worry more about the cost of an anvil, the days of $1 a pound at farm auctions were passing 20 years ago when I bought mine.

 

[R H Clark]

Considering the time and work involved,I would rather use good known steel.I buy 1-1/2"x1/4"X 5' 5160 bars for $20 each.

 

[Tirod]

Exactly the point, they are already nearly knife shaped. If not forged, many just grind them to shape on a specialty belt grinder.

 

[hso]

I am going to back up a little and say that if you have a source of FREE spikes you can practice on them and get some good experience without using good steel to practice on. You can turn out some interesting desk ornaments and paper weights to give to folks.

 

[Zeke/PA]

I saw at a recent Oyster Feast, Oyster knives that were forged from railroad spikes.
The guy did a great job on the knives and he had no trouble selling them.

 

[zxcvbob]

If you use charcoal or coke to fire your forge, won't the steel pick up additional carbon? It'll be like case-hardening, but then you'll hammer that down and forge it again -- I think your low carbon steel might end up with a low carbon core and a thick layer of medium carbon on the outside, and all the way thru at the edge because it's thinner.

 

[hso]

Not enough to matter.

 

[R H Clark]

Yea,you would have a slightly higher carbon content just on the surface but that would be ground off when you sharpen anyway.

 

[Saakee]

Why not forge weld on an other layer of higher carbon content steel over the spike? One would have the creamy nougat rail spike center with hard chocolate carbon edge holding layer on top. And now I'm craving a Milky Way bar.