Popular Mechanics (old) machining projects; reliable?

Here is the link to the article. I think I know what to do. That flimsy piece of sheet metal has to be replaced with a wrap around strap.

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Popular Mechanics

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That's the most "Mickey Mouse" set up I've ever seen......:eek 2:
 
"Tool climbing, vibration, and chatter can be expected." That is, if you don't support it with a scrap of tin foil on the back of the compound, they say.

The tool is janky, but this step for boring a hole is on the express to janktown. I hope they don't run out of c-clamps. Note the rigid mount to the tool holder, through the lantern, using the least rigid degree of freedom in the setup!

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I dunno', I think the value of these old projects is not the "how to" part; it is the idea. There are tons of older small lathes out there that do not have a modern machined cross slide table that can take a rear mounted tool and this shows you one way that it can be done. I'm sure there are others.

The cutting forces from an inverted tool mounted in the rear are transferred in such a way that most of the force is downward and behind the rear mounted tool post, towards the cross slide, not upwards and away from it. They are showing a flimsy bracket to sustain these forces and that may not be enough but the important thing is that they understood it, and now you do, too.

It isn't how to build it that is important; it is the idea that matters. How to build it to suit your needs is up to you so take the concept and run with it, then report on it so the rest of the guys can do the same ... build on your idea.

I've built several tools after seeing a single picture of a useful tool. All I needed was to understand the value and functionality of the design and how it could be applied to my machines; how to build and improve on the original idea came from me. That's sort of what hobby machinists do, I think.
 
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Reminds me of a couple hand-built match planes I have, circa 1950. They were made by "an old guy" who obviously couldn't justify the expense to buy new but still wanted to have the product the planes could produce. So he made his own out of flat bar, stove bolts, and broom sticks, all of which would be in ready supply on the farm. As mikey suggests, it's a complicated project but he clearly understood it enough to try to copy them. And yes, they do work (after a fashion), I posted an earlier little write-up on using them a couple years ago.

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Fun stuff, and even more fun to try and figure the machinations of the mind that went into achieving the improvised designs.

-frank
 
I guess the main premise of that project was to have a cut-off tool handy without making numerous set ups. But, with today's technology and a QCTP, it wouldn't make much sense to go to that much effort.
 
I grew up reading Popular Mechanics and always had an interest in the many DIY projects. I agree with the above posters that each project should be critically reviewed and judged on its own merit. There certainly was no PM seal of approval for any given project.
 
Case in point, an advice passage I just read in PM from 1934 describes how a good, cheap recipe for sandable wood filler is made by mixing asbestos with varnish into a paste and recommends sanding to shape with abrasive paper. Good for kids making model airplanes. I wish it would have had an accompanying photo of a kid hand sanding asbestos wearing khakis and a clean side part smoking tobacco pipe, that would have completed the image in my mind. The problem with common sense is that it isn't.
 
After looking at Mikey's response, and thinking about this setup a bit, maybe it will work. But he says that cutting forces are directed downward. I cannot see how this could be, since there is an axial and tangential component, and the latter is up. Even after torque is neutralized at the compound slide, the force is still up on that flimsy sheet metal bracket. After looking more closely, however, any deflection in the direction of the force will result in the tool tip following a large circular arc out of the cut, so this might add to the stability of the tool. Still, it is surprising that the author tried it and found it to work.
 
Eric, you are right, the tool works like you describe. Force vectors and directional conventions are a name game. The friction force vector is up, the cutting force vector is down. The net effect is that the tool will want to rotate about the axis in the direction of the work rotation.

My snorts and guffaws came from the attaching method on the back side. The principle of operation is sound, and the novel part is that they attached the thing to a cast iron compound, like SB or Atlas, which are hard to adapt an upside-down cutter to.
 
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