Welding Tang to File Knife,

[Hayden H]

As the title says, I ground 3 file knives in the past week using bits and peices I had laying around. Would it hurt the steel if I welded a 1/4 or 1/8 inch rod (to make a full tang with a pommel or to dissassemble it for cleaning). It'd be welded to what is already the file tang. If I do weld it, I'll wire weld with .035

[Ed Tipton]

Hayden H...No, it won't hurt a thing. This is a common thing I do all the time...not necessarily to lengthen the tang, but I usually do it to avoid having to use tongs when forging. I simply weld on a piece of 3/8 rod or something heavy enough to support the work, and it's easier than using tongs. Then after forging, I simply cut off whatever is excess, and the remaining piece becomes part of the tang. This is common practice also whenever you might have only a shorter piece of of "blade quality" knife steel and do not want to "waste" any of it in making the tang. Some really high carbon content steels can be problematic.
You didn't say, but I do hope you are planning on tempering those blades, and not using them after just grinding them. If they are not tempered, they will be too hard and brittle, and not suitable as knife blades having a tendency to break and chip out on the edge. There is a lot more to making a knife from a file than simply grinding.

[Hayden H]

They'll be hardened and tempered. I just wanted to know if it'd hurt the steel if I made the tang longer. They were a Heller file. So they'll be hardened and tempered to be mildly hard.

[Doug Lester]

Generally it is best not to harden the tang. Pearlite is easier to work with when it comes to cutting, drilling, or peening. It also helps the tang to be tougher than it would be if there was martensite in it. You will probably want to normalize the knife two or three times after welding to correct any grain growth that might have occured around the weld.

Doug

[Hayden H]

Alright. I'm gonna convince my teacher to let me build a gas forge. (Or finish one of the ones he started on last year)