240 Stainless sword

Date 04-15-2012 02:49

I've got this chunk of 5/16" stainless that I'm making into a sword. The blank is cut and now the work starts. I want the blade to taper from the hilt to the tip about 1/8"; it also has to taper from the back of the blade (5/16") to what will be a sharp leading edge. Do any of you folks have any ideas as to how to remove all this material other than the obvious - a grinder and belt sander? I am not familiar with the way stainless deals with heat other wise I would heat it and beat it into submission. But I don't want to screw up the hardness nor do I know how to get it back if I anneal it. What do you think?

Attachment: DAO.jpg (0B)

By DaveBoyer (*****)

Date 04-15-2012 03:12

If it has hardness now, it is work hardened. I don't think there is a heat treatment method that will restore hardness if You heat it.
If You decide to forge it, work it hot or it won't want to move. You would start with a substantially smaller blank if forging it.
You would need to cold work it to get some hardness.

That is a lot of grinding, any way You do it. You could mill some of it off if You had access to a milling machine.

That is a huge hunk of metal, is this sword supposed to be like some sort of historical sword, a decoration/wall hanger or what ?

By JMCInc

Date 04-15-2012 04:01

My intent is for it to be functional if desired. It is modeled after a Chinese broadsword called a Dadao (big knife). They were employed against the Japanese as late as 1930. The picture makes the handle look longer than it is. I am making it for a friend as a gift. I was going to forge it from a piece of rail road track, like the originals were, but I don't have a trip hammer and the thought of beating on a piece of RR track by hand does not appeal to me. I've made some pretty nice prybars out of torsion bars with an anvil and a singlejack, so two words w/regard to the RR track - not hapnin'.

Thanks for the reply.

A pic. of what it will look like:

Attachment: bigknife.JPG (38k)

By DaveBoyer (*****)

Date 04-15-2012 05:24

I am not familliar with them, but I think the blade would be pretty thin.

One of My friends is a history buff and makes knives & swords as close to authentic as possible. He says that for thousands of years throuout the world that a fast fighting sword has weighed about 2 1/4# complete. An original like You are making is probably quite a bit heavier than that.

The stainless would probably forge about like RR track, but will never get hard enough to hold a good edge. The 400SS group in it's higher carbon ranges [440C] is what it takes to harden by heat treatment sufficiently to hold an edge.

I would not want to forge that blade by hand either. A powered hydraulic press and tapered dies would be an alternative. I might try taperd dies in My ironworker if I had to do it.

By phaux

Date 04-16-2012 00:09

I would mill it. You could try a surface grinder as well maybe.

By DaveBoyer (*****)

Date 04-16-2012 01:31

A surface grinder would be really slow.

A coarse 2" wide zircona sanding belt would probably be the fastest of grinding methods, but there is a huge ammount of metal to come off.

By JMCInc

Date 04-16-2012 01:48

I was thinking of the 2" belt as well, after roughing it with a 7" grinder. I have a friend that works at a machine shop, I'll ask him what kind of time would be involved in getting it close with a mill.

By DaveBoyer (*****)

Date 04-16-2012 04:32

The guys making blades by stock removal use the 2" belts, usually 72" long or longer. You want at least 1 HP and a belt speed about 5,000 surface feet per minute.