File

[Jerry Thompson]

I am searching for a "safety file." This is a file that has no cutting surface on the edges. I looked in McMaster Carr and did a search but came up with zip. Is there another term for these files?

[george wilson]

Safe edge file is the correct term. I just grind off the teeth on 1 edge of a standard file most of the time. Do you have a belt grinder or a belt sander? A flat platen helps,and it takes only a few minutes.

[Gary Herrmann]

What do you want to do with it? I'll bet George can cite the names of all kinds of files we never heard of.

[Jessica Pierce-LaRose]

Like George says, safe edge is the correct term, and the one I've always heard, but it looks like McMaster is calling it a "plain edge". Just going into the site, and following the "files" link on the main page, from the categories that show up, there's safe edge files under the "Precision hand files" section, as well as the "Rectangular hand files" section (the "single cut plain edge" files) Their "knife shaped hand files" also have a safe edge on the back.

George, when grinding the edges of a file, any tips? Think it can be done well enough with a bench grinder if the edge being perfectly true isn't an issue? I haven't done this before, but it's occurred to me at times, but I've never attempted it.

I need to get my own belt grinder, making the trip out of the house to use one on the few times I need it is a pain.

[george wilson]

The best tip I can think of is to hold the file vertically against a flat platen on a belt grinder. Your belt sander will work fine,but CLEAN it real well. You don't want to suddenly find rust specks(they may be blue) all over a future wooden project that you have sanded and used water based stains on. Even with subsequent finer sanding,those little specks of steel can still remain on your project. Use a finer belt,and keep the scratches going parallel with the side of the file. Those scratches can file too,where you don't want any marks. So,keep them fine and parallel.

McMaster Carr must have an inexperienced person naming their tools.

[Jerry Thompson]

I am going to use the file to open up the mouth on a #5 SB. I put a Hock blade and CB in it and even with the frog way back it acts more like a smoother than a jack. It can sure put out the fluff though.

[Jessica Pierce-LaRose]

The fact that the scratches from removing an edge can mar the work slipped my mind - so obviously, like you said, you'd want the scratches parallel to the file - which kind of makes using my bench grinder out of the picture. Not really sure how I'd safely grind the file in that direction on a grinding wheel.

My fathers got one of those belt/disc sander combos, we use it mostly for metal tasks. There is a platten below the belt. Maybe I'll take a couple files over tomorrow and see what I can get. I've got some extras kicking around, and have hit a few projects where another safe-edge file would be useful.

[george wilson]

Indeed,watch makers(and I) used a trick to make super fine files: They made a needle file from annealed tool steel. They dragged it diagonally across medium grit wet or dry paper. When it was hardened,they had a very fine file for super finishing delicate parts.

I have made some of my riffler files like miniature knife steels. I dragged them across the teeth of a tight jeweler's saw blade until tiny grooves were formed. Then,they were hardened,using a protective layer of PBC No Scale from Brownell's. I've also used an old recipe made of water,flour,and some yeast. Made into a pancake batter consistency. The files were dipped into it,then heated red hot. The batter burned,leaving a thick layer of carbon on the file which protected the surface,and was easily brushed off after hardening and quenching. I'd then dip the small file in water,and heat it till the water sizzled,wait 2 seconds and quench. This was known to old timers as "taking the snap out of it". The file would still be close to 65 Rockwell,but not as brittle as when simply quenched. W1 will reach 67 R.C. when hardened,but has very little mechanical strength against snapping off.

[Steve Bates]

I've used a grinding wheel to make a safe edge on a file. Take off the tool rest to open the wheel's guard below. LIGHTLY touch file edge to wheel starting at top of file. That way, if it catches, it'll drive it down out of your fingers. Keep your feet spread apart because you don't want the file to bury into your toes.

A belt sander is better/safer as George stated.

My two pennies

[Roger Davis IN]

Jerry:

The "other term" is "pillar file," although other types can and do have safe edges. Search McMaster for "pillar file" and you will find a small selection (used to be a lot more sizes, I think).

[Larry Williams]

I am searching for a "safety file." This is a file that has no cutting surface on the edges. I looked in McMaster Carr and did a search but came up with zip. Is there another term for these files?

A lot of Swiss pattern files have safe edges. I usually use Swiss pattern pillar files when I need safe edges but there are others. Some Swiss files have one safe edge as well.

[Jim Matthews]

Is there any reason why you couldn't paint on nail polish (or something else cheap, and readily available) to blunt the side teeth?

[Peter Evans]

American pattern Files with one safe edge were/are called "hand files". With 2 safe edges "Hand Finishing" files. Some Warding files also have 1 or 2 safe edges, and are ideal for cleaning up plane mouths - the thin profile avoids filing where you do not want to, and they flex enabling a small rounding over. Modern Warding files made wherever do not flex however - but snap instead. You need to go Swiss.

[Trevor Walsh]

Indeed,watch makers(and I) used a trick to make super fine files: They made a needle file from annealed tool steel. They dragged it diagonally across medium grit wet or dry paper. When it was hardened,they had a very fine file for super finishing delicate parts.

I have made some of my riffler files like miniature knife steels. I dragged them across the teeth of a tight jeweler's saw blade until tiny grooves were formed. Then,they were hardened,using a protective layer of PBC No Scale from Brownell's. I've also used an old recipe made of water,flour,and some yeast. Made into a pancake batter consistency. The files were dipped into it,then heated red hot. The batter burned,leaving a thick layer of carbon on the file which protected the surface,and was easily brushed off after hardening and quenching. I'd then dip the small file in water,and heat it till the water sizzled,wait 2 seconds and quench. This was known to old timers as "taking the snap out of it". The file would still be close to 65 Rockwell,but not as brittle as when simply quenched. W1 will reach 67 R.C. when hardened,but has very little mechanical strength against snapping off.

George, I'm a total sucker for tidbits like this. I'm planning on building a clock soon (hah, what has my definition of soon devolved into?) spured by the early Hardinge Cataract lathe I just bought. I can't wait to make some tiny fine files.