The Home Machinist!

Try to read/study filing on the lathe, or filing in general. Aluminum has a habit of pinning the file, which means the gullets in front of the file teeth clog with the aluminum removed. This "pinning" of the file is exagerated when filing aluminum, it's soft and will heat up with the friction, a pinned file can be quite difficult to clean.
The other problem is that the pinned file will gall the surface of the aluminum leaving grooves around the diameter of the work requiring more metal removal to get a good finish.
Not to scare you off, just a warning, when you buy your long angle lathe file make sure you get a file card (like a wire brush with very short wires. and use it often as you are filing.
Here's a link [url]modelsteam.myfreeforum.org/.../using-files-basic-filing-techniques_...[/url]

I agree. I rarely recommend filing on a lathe---and never when attempting to form precise surfaces (turns for bearings, for example), but for this type of application, where minor error in roundness isn't a problem, it makes doing a project that might be impossible, nothing more than a simple challenge.

Pinning can be cleared by using a piece of thin material that is pushed along (parallel with) the teeth of the file. That works when file card struggles. I have a piece of 1/16" thick titanium that serves that purpose, and has done so for more than 40 years. With the first stroke, the cleaner conforms to the teeth of the file and will remove pinning completely. It's faster than a file card.

Two alloys of aluminum minimize filing problems. One of them is 2024 in T3 or greater condition, the other being 7075-T6. Both will cut without streaking, and leave respectable finishes. Both are considered aircraft grades of alloys.

Harold

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Wise people talk because they have something to say. Fools talk because they have to say something.

you may also find that chalking the file will help with stuff not sticking if you are dry fileing as a safety note get a file handel also. or a big first aid kit.

WD-40 on the file will help prevent sticking the aluminum in the teeth, just as it helps when turning. As mentioned, the file card is your best friend on this job.
There are special files for lathe filing. The teeth are at a much greater angle than those on a mill bastard. This helps to shear off the material. I have a 12" Simmons that has LATHE stamped right on it by the trademark.

--earlgo

Can someone elaborate on the file card and cleaning files? I've thought I've ruined some by flattening the edges but maybe they are just plugged.

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Standards are so important that everyone must have their own...
Logan 10x24 Lathe, RF-30 Mill, 20 Ton Press
Disclaimer: I'm just a guy with a few machines...

The file card works OK, but to really clean a mill file, I prefer taping some aluminum sheet to a putty knife. Push it in the direction of the grooves in the file and the aluminum will conform to the file pattern and clean everything out righ down to the roots.


Some do the same using a slice of hardwood.

Using chalk will keep it pretty clean.

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Glenn

Operating machines is perfectly safe......until you forget how dangerous it really is!

If you've used the file card like a brush, working front to back on the teeth, that's a mistake. File cards have heat treated wire teeth that are very capable of destroying the cutting edges of files. Some folks insist they shouldn't even be used.

To use one with minimum damage, to both the file card and the file, draw the file card parallel to the teeth of the file. Don't push! The offset of the teeth is intended to dig in to the file, to remove pinning. If you push, the teeth float over the material and gradually lay down, never to stand up again.

You are well served to follow the lead both Glenn and I provided---using a thin piece of metal, parallel to the teeth. It's' faster, works better, and doesn't harm the teeth.

Harold

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Wise people talk because they have something to say. Fools talk because they have to say something.

Apparently Bamboo can be used instead of aluminum or other "softish" metal. I've yet to try it myself, I'm waiting for the Pandas to leave before I cut some bamboo.

Might giver 'er a try this weekend on some smaller stock. Will try doing it by hand with the cutting tools and gradual feed (how to say that? In other words, I'll try an HSS tool in the holder and use the dials to work it). No free handing with the files just yet.

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You never know what your faith is until your faith has truely been tested.

A piece of hardwood can be used, too, but if the pinning has attitude, it just removes the wood instead. That's why a piece of metal is more desirable. You can see how well the piece of aluminum works for Glenn-----results I get are the same from the titanium I use. Aluminum is far more readily available. I lucked in to the piece of titanium, which is rigid enough that it needs no further support. I'm not promoting its use---just suggesting that if you happen to have some available, it works well.

Harold

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Wise people talk because they have something to say. Fools talk because they have to say something.

Titanium, Aluminum, hard wood, bamboo all works.
I flattened a 1/2" copper pipe on end and soldered a cap on the other, drill a hole radially to hang, presto a round handle and a flat soft metal edge.
Not yet found a subborn enough pin that could not clean out.

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Mauro Gaetano
in Austin TX

I use an piece of 357 Magnum brass, hammered flat on the open end and annealed, with the primer end jammed into a worn out (drilled to press fit) file handle. Readily takes the set of the teeth like a really stiff coarse brass brush. Works great and allows "focus" on problem areas when they arise.

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Russ
Master Floor Sweeper