Mystry file

[DuEulear]

So a while back when i first started blacksmithing i purchased a box of 100 new old stock random files for $ 50 figuring anything i did not want i could always forge into somthing else in the box came all manner of single cut and double cut files and rasps rounds triangular half round , bandsaw files..... along with all that came three files? Made by nickelson usa that look like the following images it may be hard to tell but there are only file teeth cut on  the lower half of the back. The sides are smoth and it is shaped like a knife file but all descriptions i have seen for knife files would still have teeth cut into the flat sides of the file? The crossection is a long wedge with a square back. 

 

Anybody have any ideas what the intended purpose of this file is?

 

 

[Lou L]

My guess is that someone ground out those sides to create a “safe edge” so they could file away knowing they wouldn’t affect adjoining parts of the work piece.  It’s a pretty common practice that had no idea about until recently.  Must have been a really weird spot to file.

[Kozzy]

Dang it...I know I've seen that file style and use before and it's buried in the rusty recesses of my brain.  I'm going to be stewing and trying to remember to the point where it drives me crazy.  Seems to be filed (no pun) in the same bent-brain cabinet as babbitt scrapers of old...

[Frosty]

So prisoners won't scuff their hands filing their way through the window bars? 

Maybe for filing keyways?

Frosty The Lucky.

[sfeile]

That is called a Knife file with a safeback. They are normally used by tool and die makers. The smooth edge or safeback is to keep from unintentionally marring the workpiece.

[DuEulear]

The back is the only part that is cut? The two flats are safe, and the file is factory new. I could see using it to file the very corner of a square notch in a part though. It seemes to me i would want to blunt the edge not in use though as it is sharp like a knife.

 

Filing keyways seems like a pretty good use though frosty.

 

thanks 

 

[BIGGUNDOCTOR]

I would also say a keyway file. The ones that were ground smooth all over were bearing scrapers, you can still find boxed sets of them.

[sfeile]

[Frosty]

Arghhh, die files! That should've been obvious to me dang TREE. Filing keyways is die making. A file with a safeback would be a REALLY a handy file for that tool box. Hmmmmm.

Frosty The Lucky.

[DuEulear]

The sides are not cut the back is rough or bastard cut

i can see how it would get you into the corner of a right angle notch as the safe side riding the side of the notch would raise tge back enough to grt into the 90  degree corner

[Kozzy]

It's got me a bit confused as to the cut.  I just pulled one out of the new bin of files that was exactly the opposite of yours, no cut on the spine but cut everywhere else as expected.

I did find one partial reference that wasn't enough of a "sure thing" to post--same style file, implied it had safe sides, used in piano work--such as when you re-key and need to file the notch/cutout in the white keys to length in order to clear the black keys.  There wasn't enough info to confirm the file was the same as yours but I can see that being a reasonable use for one that is safe in the sides and only cut on the spine.

[DuEulear]

Sounds like a posibility all the same i whish it was an ordinary knife file i would have more usefor it. Pehaps i will just make a knife file knife...

[DuEulear]

Thanks again for all your help guys

 

du