The main problem with good files to make into knives, without Hting or annealing, is the way they are Ht'd to begin with. Files are very hard to give the multiple (little) edges the ability to be sharpened and resharpened. Files are not ment to be bent so they don't take to it to well, I've actually seem them shatter when a farrier pop a horses butt for acting up,that is osme hard steel! Now saw blades do have some ability to bend a tiny,tiny bit. Most of the good ones are or were L-6, which is good knife steel. I agree with Dale, if you keep them cool while grinding, actually if you don't allow any heat build up, meaning dunk it after each pass, and keep your blades short, so no flex is possible in the knife, you can make a decent serviceable knife with either steel.
Now for the holes needed in the tang,...it "can" be drilled with a carbide bit...but these bits, depending on size are EXPENSIVE! And drilling into this type of steel is more than frustrating, if you flex these bits a tiny bit they will break, if you get a hole started and the heat builds up too much, it will work harden. That's when your drill pess will start rattling and the drill bit will start squealing a painful screeching sound, using cutting oil should help...maybe, you can anneal the tang by heating it up to non-magnetic and then a little more, and the bury it in the middle of some hardwood ashes, or better Vermiculite. Wood ash is easy for anyone to get, Vermiculite is carcinogenic, and not recomended in areas that may have kids. It's not good to just have around, breathing it in is hazordous to everyones health! I went with wood ash, it should take it a day or so to completely cool, if it cools faster than that, you need more ashes and/or an insulated container.
I have saved many files from many farrier friends, they give them to me if they don't send them back to be reshapened, so I have a few around the shop, if I ever run out of known steel, I'll go to them then! But not until I have to.
Mind me asking why you aren't using known steel like what Aldo sells? Some of his 1084 makes an awesome knife, and heat treating it is as simple as it gets. Almost foolproof, that is why I started with it and still use it, like many makers do, including the big time guys you would think would be using something fancier, but because 1084 is pretty hard to beat for a using knife, with an inexpensive price tag for the annealed steel. Check with Aldo after Blade, buy some of his 1/8", 3/16", or 1/4", you'll be surprised how much better your stuff turns out. Hope this helped, Rex
McClellan Made Blades
Deatsville, (Autauga Co side) Alabama
My Avatar is a knife I made, I call the "BEAST" with a wicked HAMON!!!
"Try not, do or do not, for there is no try." ~Yoda~