Filing techniques

P

pso

Joined
Oct 29, 1998
Messages
494
Hello

Can someone give me some pointers about filing technique? I keep seeing the term "draw-filing". How is that done and when would one use it? I have been "pushing" the file along it's long axis to make my cuts. This works well with the bastard file. The Black Diamond smooth cut file "clogs up" with the metal, even if I apply chalk to it. Without the chalk, it will gouge or gall the metal.

Thanks again for your help.

Phil
 
Phil; for draw filing the general rule is right push and left pull. This is reference to the tang end of the file. To draw file lay the file across the blade at right angles to the blade with the file tang on your left As you pull toward your body change the angle of the file to the blade slightly, you can feel it when it really starts to bite cleanly. Finish the stroke, pick up the file and make another pass. A new sharp file will remove an amazing amount of metal in a short time. Clean with a card every few strokes, whether it needs it or not, the small bits are what catches the large chunks and makes you cuss.Use files like a grinder, start coarse and go to finer ones when you get close. For me single cut files work much, much better than double cut files. You can get single cut files from bastard to smooth cut. Put a staight board edge up in your vise. Clamp your blade on top when you file. If the board is no thicker than your blade is wide it won't be in the way and the blade won't flex away from the file. This makes your filing much more precise. I make sens out of small planer blades. The angle is about right on the edge and they stay sharp a long time. You can push or pull it. I'm not good enough with one to give too many pointers tho. mw
 
Peter, can;t post pics from here. But it is real simple. A 1 inch wide 3/16 thick planer blade about 8 inches long. Handles are friction tape wrapped around each end. It is ground on one side only; chisel ground; at about a 45 deg. angle. I touch mine up on a 320 grit belt. But stones work too. Tool is simple. Technique is a little harder. mw
 
So you must lift the file from the piece before starting another pass?
I file going poth ways: push-pull-push-pull and so on.
What really annoys me is that I must clean the file every pass, or it will gouge the metal. I'm filing stainless steel. Is it more difficult than plain carbon?
I catually don't mind it, until I'm close to final size, where I must start worrying about the surface finish of the metal, but isn't there any way to prevent this without having to stop to clean the file every stroke you give?
I've tried cutting oil but it seems to make things only worse.
 
When I file away the steel with the big bastard file I don't care much about the deep scratches. Then I switch to a fine file and take out the deep ones keeping, making sure that the file is clean and won't put back other deep scratches. Then I wrap 180 grit sandpaper on the same file and "file" away. It works surprisingly fast and you don't have to worry about scratches, just change the sandpaper every two mintues or so.
I use push-pull strokes, not sure it's the right technique but it works for me.
 
Well, I don't know if I have much to add seeing as how m l williams taught me how to draw file. It was amazing to watch him work with those files. A real eye opener I'm telling you! But anyway, here's what I do know from my experiences.

I took what Mike taught me and went home with it and figured out a few things on my own that made life easier for me. One of the first things I did was pick my files that would be dedicated to draw filing and modify them a bit. Not much, just a little smoothing of the sharp angle on the side facing away from me when I do the push strokes. I used a belt sander with 220 grit for that. That will keep you from getting deep scratches at the choil when working on the bevel or grind. Do that on both sides of the file so you can occaisonally flip the file over and get full use from your files. If you're left handed you'll have to smooth the other side edges of course. You still get small grooves at the choil but they come out easy enough with hand sanding.

The other thing I figured out was how to keep that file clean without stopping to card it every time. But it's very important that you first understand how sensitive you need to be with the whole draw filing process. When you get a burr stuck in one of the file flutes you can feel it immediately if you're tuned in. It's like fingernails on a chalk board. EEEEK! So, as you're draw filing try this method. Make a pass and whack the tip of the file on a wooden surface like your workbench (you'll see the small particles fly off of the file) and then sweep your hand down the file going with the direction of the flutes from the handle to the tip, not against them. You'll begin to work up a very nice rythm with practice. Stroke, whack, sweep. Sure, it makes your hand black but you're used to that being a knifemaker. When you do get that monster burr stuck in a flute stop and card the file. Or you can cheat like me and just pick it out with yer fingernail. Keeping a gentle, steady even pressure on the file will keep you from getting those nasty burrs though. Unless it junk in the steel. It's not like grinding on a belt grinder. Pressing harder doesn't necessarily work better and remove the metal faster. Pressing harder will create a whole army of those burrs to make you cuss.
 
Don't know about the stainless, I have never done any. Max, I don't do the whack, but I do drag it against the heel of my hand every other stroke or so, gets the little stuff early. You do develop a feel for the cut. mw
 
Well, I probably picked up that habit of sweeping my hand across the file from you Mike without even being aware of it. But you should try the whacking trick. It gets about 90% of the crap out of the flutes before you rub it with your hand. Whatever the whack misses the hand rub will usually get. I used that technique this afternoon on a few knives I'm working on and it still amazes me how smooth you can get that blade with just a file. Of course I switch to wrapping the file with 220 grit sandpaper when I have the shape I want to clean it all up and get it ready for heat treating. Thanks again for all those cool tricks you showed me in school Mike. They have saved me lots of aggrivation in the shop.
 
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