Redneck lathe

Today I was faced with having to produce a 10 mm x 18 mm mild steel cylinder. Not having a chop saw or similar I stuck a piece of stock in the chuck of my 8" drill press, improvised a scribe and marked out a circumferential line where the cut was to be made. I made the cut along the line (more or less) with a hacksaw. It was not too bad, but not quite flat and not quite at right angles to the sides.

This is where the problem came.

I do not have a lathe. All I have is a drill press and a 6" disk-4X36 belt sander. I just could not get the cut straightened up. The disk sander has a degree of give in it so pressure causes a variable deviation. The mitre gauge has a minor degree of play. I tried switching to the belt sander in a vertical position and the result was even worse. In any case one does not relish getting one's fingers that close to abrasive material at high speed.

In the end, this is what I did: I clamped the cylinder in the drill press chuck so that about 6 mm stuck out. I found an old file which was quite big and flat. I clamped it to the drill press table. I slathered it with a cutting compound, turned the drill press to 1500 rpm and lowered away. It took quite some time but the result was really quite good.

Unfortunately I slightly spoiled the result through impatience: The file was not cutting fast enough and I thought I would try to wrap it in coarse sand paper. With the most stock removal happening at the periphery and the slight "give" of the sand paper the cylinder is ever so slightly convex rather than perfectly flat.

I am not sure how many safety commandments I violated but it got the job done.

Does anyone have any suggestions how to tackle a similar problem given limited resources and definite lack of manual skills?

Reply to
Michael Koblic
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I would cheat.

Borrow a 1/2" drill motor. Wrap a couple layers of masking tape evenly around the butt end of your workpiece. Chuck up the taped end and brace the body of the drill motor (with the power cable facing away from the center of the earth) against your belt sander table. Run both sander and drill so that your workpiece axis is oriented at right angles to the belt.

With the drill motor 'upside down' like that, your workpiece will be much more controllable and won't tend to tear holes in your belt. It will tend to 'kick' *away* from the belt when it catches. This is devoutly to be desired.

This also works for putting a neat chamfer or radius on the end of your workpiece.

--Winston

Reply to
Winston

Get a drill press and a big file :-)

Bruce-in-Bangkok (correct Address is bpaige125atgmaildotcom)

Reply to
Bruce in Bangkok

Smiley or not, it worked. On the other hand, you have an issue because the center is turning but not moving relative to the file, therefore not cutting. For flat, I like Winston's approach. I've used similar.

Reply to
Pete Keillor

I had the manual skills (verbally) beaten into me in Jr High wood shop. The old Swedish cabinetmaker who taught it made us plane and file blocks of wood square enough to show light evenly against a try square before we could use the power tools. The experience made us really appreciate accurate machinery and able to do a good job where the common machines don't help, like sharpening a plane or chisel blade.

Filing an end square is much easier if you have a long guide surface. In this case you could hold the cylinder in saw grooves between two blocks of wood and use the outer edges of the wood as the guide. A good coarse file cuts steel pretty quickly and a "hand" or "pillar" file makes a nice finished surface. Put some tape on the wood so if the file hits it will catch the tape rather than lower your guide surface.

Jim Wilkins

Reply to
Jim Wilkins

On Thu, 15 May 2008 23:14:31 -0700, with neither quill nor qualm, "Michael Koblic" quickly quoth:

This is gonna be one of those "Hey, y'all: HOLD MY BEER & WATCH THIS!" posts, isn't it, Mikey? ;)

Yes. Before you need machining work again, find someone local who has a small machine shop and become friends with them. The digits you save may be your own! Advertise in the paper if you have to.

"WANTED: Friend with machine shop to help make fun small stuff."

- Press HERE to arm. (Release to detonate.) -----------

Reply to
Larry Jaques

--FWIW a pal of mine from the old neighborhood made an R/C helicopter back in the very early days of same, using a file and a drillpress. Impressed the heck outta me and everyone else who saw it fly!

Reply to
steamer

Well, if that's what you want, I can help.

I've seen grown adults that should have known better chuck the work in the drill press spindle, grip a lathe tool in the drill press vice and hand-feed it into the work while it spun. Not recommended.

Reply to
Jim Stewart

Pete Keillor wrote in news: snipped-for-privacy@4ax.com:

For a similar "project" - I didn't have a sander like his - I simply center-punched the end of the piece and, then, worked it on a clamped-down file until the center hole disappeared.

FWIW, it helps - a lot - to have the file clamped down so that the edge toward the center of the piece is barely _at_ the center. This allows the file teeth to function properly and provides an "escape route" for filings.

Reply to
RAM³

There is no doubt that there are exceptionally skilled people out there. In the old country, where needs must, people would make all sorts of things out of stuff they had available.

I was into ham radio then and made my share of stuff, but what some of the others could do was amazing. There was guy who reproduced the Collins "S' Line (a top of the line transceiver with a power amp and a tuner) by painstakingly making his own component parts. In the process he had to make all kinds of special tool (coil winders etc.). He made the national magazine.

Others believed in adaptability and liberally adapted assorted Wehrmacht equipment to their uses with considerable success.

Sadly, I can only dream of that level of skill.

Reply to
Michael Koblic

It is good to now that great minds think alike :-)

Reply to
Michael Koblic

I have try it again, this time with the file only. I suspect that the sand paper screwed things up ever so slightly. Maybe even get a new, bigger file, one that is not over 25 years old...

Reply to
Michael Koblic

Clamping down - essential! I tried that hand feed thingy but had to dodge the end of the file once too often... BTW my indicator of success was appearance of pleasing concentric rings.

Reply to
Michael Koblic

What, next thing you will be telling me to buy my meat in the supermarket!

Reply to
Michael Koblic

LOL! I actually thought about that...too scary even for me!

Reply to
Michael Koblic

I use my mill as a redneck lathe. I even bought a R8 backed lathe chuck for this purpose. Works kind of OK.

i
Reply to
Ignoramus620

Get a selection of good ones and don't dump them all together in a drawer. My largest file rack is a plank hung vertically on the wall with pairs of finishing nails driven in at a downward angle to hold several dozen files. I used a triangular strip of wood as a guide to drive the nails.

Jim Wilkins

Reply to
Jim Wilkins

Now that is interesting, I had a similar thought just an hour ago: Would a

3/8" end-mill work in a drill press? My drill runs slowest 720 rpm but according to the tables this should be OK for mild steel - certainly for drilling. Does this applies to mills, too? I would have thought the feed speed will be critical but maybe not.
Reply to
Michael Koblic

It will certainly not work if you are on a morse tapered spindle. The drill chuck will fall out due to transverse forces.

Reply to
Ignoramus620

Even when "worn out" and/or seriously abused, files make good raw material for knife blades.

Reply to
RAM³

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