How a Cedge project is born

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Cedge

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I like to file metal. I know it's mindless drudgery, but I can get a lot of thinking done while accomplishing something constructive. Weird?... maybe, but it's one of the ways I cogitate. Hey... Marv Klotz highly recommends such mindless activity...LOL

Last year I attended a huge used book sale and picked up a set of 1955 Popular Mechanic's Year books. It's a fantastic 12 book set of plans, instructions and tips for darned near anything you can think of. I've enjoyed the books far beyond their $15.00 price. In one of the volumes is a set of drawings and instructions for building a small motorized filing machine. The design is pretty simple and the instructions state that amazing accuracy and beautiful contours can be had by using the little machine, while saving lots repetitive motion.

I've been mulling the idea of building one, ever since, with an eye toward using the lathe as the power source. I'd pretty much worked out the kinks in my mind... well sorta....and the project was on my list of "to do's" when I got another "round tuit".

As some of you know, I made a nice used tool purchase from an old guy, name of Clarke, the other day. I returned today, at his invitation, and picked up a few more odds and ends that I thought I might find handy. In the mix was a small and unusual little tool that I immediately knew would become my filing machine. I got everything home and put away, then I dug out the "portable jig saw" and began playing with it. Below is a progression of the process as I thought my way through how it's going to work. I thought it might be fun to do something a bit different and let everyone follow along on an unscripted "build" and to share the paths it takes along the way.

Here is the $3.00 oddball little beastie, as I found it. I have no idea what would have driven it in normal use. It's a freestanding unit with a 1/4 inch drive shaft which appears to be used in a chuck of some sort.

jigsaw1.jpg


After a little clean up, I had a peek at the internals and found it was a "scotch yoke drive instead of gears. Nice, since it's a sturdy mechanical engagement and pretty easy to repair if things go pear shaped sometime in the future.

jigsaw2.jpg


After a bit of study, I decided the existing shaft was a little short to safely chuck in the lathe without the jaws striking the body, so I rummaged in my newly organized tool boxes and grabbed a small flea market find I had picked up a couple of months back. It's a small 1/4 inch drill chuck with a straight arbor which is about 2 inches long. It's a beautiful fit and it added just enough extra length to make things feel a little more safe.

jigsaw3.jpg


Here is the little unit positioned on the lathe bed and chucked up for a test run. I tried it with the base plate on top, but that configuration raised the proposed work surface a little higher than felt comfortable. By rotating the assembly 180° it lowered the work zone and mated up perfectly to the 1/2" aluminum bar stock that will probably form the new base. This added a lot of stability and killed the little bit of existing vibration in the system.

jigsaw4.jpg


The photo shows the elevation of the proposed work surface. The plan is to front hinge it so that filing an angle will be as simple as adjusting the table to the required degree and locking it in position. The table will also be longer to the right, in order to give a bit of extra working room. If you look closely, there is a small chip shield sitting on the chuck end of the table. This will be mounted on the right edge and will provide some protection from the spinning chuck. The larger shield on the lathe can also be brought into play if needed.

jigsaw5.jpg


Here is the configuration, shown in context of the general work area. There should be enough room to comfortably operate the filing table, but I'm sure some adjustments will come as this one progresses.

jigsaw6.jpg


Hang with me, here.... this little project has no specific time frame or specifications and I'm sure it will take an interesting twist or two before it's done.

Steve




 
Cedge, this will be one that I keep my eye on! That little adapter would be an easy enough thing to make by itself, and I can see some uses for it. Keep us in the loop!
 
Steve: OH! now you have made me feel bad. When we cleaned out my folk's house there was something like that and I think it went in the estate sale. Dad must have picked it up at a garage sale as I sure do not remember having anything like that around when I was living at home. It was a jigsaw attachment for a hand drill, it never entered my mind that I could have made it into a die filer. Now I will look for it in Dad's tools and see if we kept it somewhere.
don
 
Lathe as power take off. Nice! Given the variable speed on my lathe, even nicer!

And I agree, said gizmo not hard to make. FWIW, I've seen small handheld recipro saws with dead motors canibalized for this purpose too.

I've heard good things about die filers, but never messed with one. I do know I use my disc sander I made constantly, and this seems like an equally flexible and useful tool.

Best,

BW
 
Steve,

I only recommend mindless activity because I'm so good at it. :)

Like you, I hound all the library sales. Over the years I've scored dozens of copies of Machinery's Handbook for less than $5 as well as multiple copies of Mechanical and Electrical Engineer's handbooks at a buck or two apiece.

Generally what happens is that there won't be anything at the monthly sales for a long period. Then some old-timer will die and his relatives dump his collection at the library and, if you've been patient, it's gloat time.

I built a mini die filer similar to yours. I wasn't lucky enough to acquire a ready-made Scotch yoke mechanism so I built one. I didn't bother fitting it to the lathe. Instead, mine clamps in the vise and is driven by a variable speed hand drill.

Die filer files are hard to find (and expensive when you do). Since mine is a small unit, I use needle files. It's fairly easy to grind the ends to fit the chuck so they can be mounted to cut on the downstroke. I've also used cheap Chinese "diamond" needle files. Since they cut in either direction, one can use the supplied handle in the chuck.
 
Marv...
I'd love to see photos of your setup, as well. We seem to be thinking on the same wave length. The hobby needle files are what I'd planned to use as well, with an option to switch to larger if needed.

Part of the reason I've enjoyed the PM yearbooks so much is that so many of the home projects that were of little note in 1955 could easily bring Homeland Security down on top of you if you tried to secure the materials they recommend, today. It's a real window into just how much the world has changed, for much less than the better.

Steve
 
Cedge said:
Part of the reason I've enjoyed the PM yearbooks so much is that so many of the home projects that were of little note in 1955 could easily bring Homeland Security down on top of you if you tried to secure the materials they recommend, today. It's a real window into just how much the world has changed, for much less than the better.

I got into a discussion with the local middle school science teacher* about the origins of the electric motor. I offered to build the school a model of Faraday's original device as a demonstration. When I described how it involved a wire rotating around a magnet in a pool of mercury, she absolutely freaked. Learning has been completely subordinated to the irrational fears of a bunch of yuppie enviro-nazis.

----
This is the gal who teaches her students that, if there were no gravity, all the satellites in orbit would fall to earth. :eek:
 
This is the gal who teaches her students that, if there were no gravity, all the satellites in orbit would fall to earth.

Oh dear, those poor young minds, frightening that our future is in thier hands.
 
Cedge--I'm going to follow along here, because right at the moment I haven't got the foggiest idea what your end result is going to be. I don't know what a die filer is!!!
 
Ok, here are some pictures of my rig. Nothing special about it. The yoke driver is simply a ball bearing screwed to the disk that rotates. The oscillating shaft runs in brass bushings let into the aluminum supports. Otherwise it's just "form follows function".

The file lying next to the device shows my approach for mounting the files. The end of the file is ground to a cylinder and then (soft) soldered into a short length of drilled out 1/4-20 brass screw. This screws into a matching thread in the top of the oscillating rod and is secured with a lock nut. This arrangement simplifies orienting the file to the work and to one's position relative to the machine.

The brass disk just under where the file attaches is there to prevent filings from getting into the bearings and mechanism. It would work better if it were conical in shape - think umbrella. Make the hole in the table (through which the file projects) an aliquot size with a counterbore so you can easily fit bushings that closely match the file size - important if filing small parts but less important if you make big stuff.

FILE1.jpg


FILE2.jpg


FILE3.jpg


A less flexible, though still very useful, approach is to make a vertical table for your Dremel. This substitutes the rotating Dremel bit for the vertically oscillating file but is still capable of some very fine work if one exercises some patience and jury-rigs some suitable fences.

dremel4.jpg
 
Brian
With the current energy crisis going on, I'm trying to do my part. By automating the mundane chore of filing, I hope to save huge amounts of elbow grease. In fact, if I manage to save enough, I plan to export it.

While many Asian countries have an over abundance of the smelly stuff, I'm told there are severe shortages in parts of Europe. A number of Asian countries and several from our own southern hemisphere have tried to supply them, but it appears their supply is often rejected as being of an inferior grade. I figure a high grade of good old fashioned American made elbow grease just might be the ticket to breaking the embargo. Just doing my little part to save the world.....eh?

Steve
 
Steve---Perhaps I'm having a stupid attack. In the last photograph of the first post, you have what appears to be a 3/4" thick aluminum plate mounted to the top side of the jigsaw attachment opposite to the side which the blade comes out of. Are you going to put a hole in that plate and somehow have the blade come out the opposite side of where it originally come out of the jigsaw attachment?
 
Brian
Not being a mech-a-maniacal engineer is its own blessing...LOL You are indeed right, the bloody thing is definitely "inverted", but I'm not skeered of that. There is actually method to the madness, in that if that little jumpy thingy doober points upward, the work surface is raised by about 2 inches.

As a matter of ergonomics. It's just plain uncomfortable at that height and would not be much fun to operate. By rotating it 180° I gained more than one advantage. The table drops to a much more comfortable level and I get a perfect mount point to stabilize the assembly while gaining several nice and convenient places for the tilt top option, I plan to add, to bolt up.

The applied motion will simply be transferred to a second vertical rod which can run in a much larger bushing. This will also have an adaptable chuck to allow using several different types of files. Since there are no obstructions beneath the base, I could even bush things a second time to increase stability even more.

Basically I'm just adapting to an existing set of parameters and working toward using them in the most user friendly manner. Here in the deep south we call that Shade Tree Engineering....(grin)

Note to self... be sure to drill hole in top table plate for the new jumpy thingy doober.

Steve
 
Believe it or not, I seen a very similar "how to" article in an early 1960's Popular Mechanics, using a treadle sewing machine to build a sabre saw, on which the blade stuck up through a plate similar to what you plan.
 
To answer Brains question, a Die filer is for ----------------- Filing Dies. :big:
In the Pre-historic days BCNC (Before CNC) when yer wanted fancy shapes punched out of sheet metal and used press tooling, (Long long before Lasers and Jet cutting,) you had to cut an approximate shape in the unhardened Die plate and then get an Apprentice to file like buggery for days on end to get the shape. If you were a Skilled man and a slaveling was not available, so you didn't have to break into a sweat, you used a Die filer. the file poked through the table and cut on the DOWN stroke, like a bandsaw does, and if you're very clever you only need to use one hand on the Die block, leaving you able to use the other one for smoking or leaning on.
Sorry to disagree in using the Lathe as a PSU Cedge, bits of filings allover the bed, a bit like using the spindle to rotate a grinding wheel. A windscreen wiper motor from a commercial vehicle is a much better bet, and for those not lucky enough to have the "Gearbox" you have, a good basis for the reciprocating drive.
Regards Ian.
 
Circlip said:
To answer Brains question, a Die filer is for ----------------- Filing Dies. :big:
In the Pre-historic days BCNC (Before CNC) when yer wanted fancy shapes punched out of sheet metal and used press tooling, (Long long before Lasers and Jet cutting,) you had to cut an approximate shape in the unhardened Die plate and then get an Apprentice to file like buggery for days on end to get the shape. If you were a Skilled man and a slaveling was not available, so you didn't have to break into a sweat, you used a Die filer. the file poked through the table and cut on the DOWN stroke, like a bandsaw does, and if you're very clever you only need to use one hand on the Die block, leaving you able to use the other one for smoking or leaning on.
Sorry to disagree in using the Lathe as a PSU Cedge, bits of filings allover the bed, a bit like using the spindle to rotate a grinding wheel. A windscreen wiper motor from a commercial vehicle is a much better bet, and for those not lucky enough to have the "Gearbox" you have, a good basis for the reciprocating drive.
Regards Ian.

Circlip--Thank You. I kind of had it figured out from the nature of the post, but it always surprises me---For a man that has been around technology since Adam was a pup, both from the engineering office side and the shop floor side, things still keep popping up that I haven't seen before.---Brian
 
Press tooling ain't Technology Brian, It's smashing the Excretae out of sheet metal.
 
Brian
If you love gadgets and old tech, the 1955 PM yearbook is often on Ebay for very little money. It's a fascinating 12 volume set that has oodles of information on an astoundingly wide range of subjects and projects... including quite a bit of machining tips and instructions. I highly recommend it to anyone.

Ian...
Now you have my curiosity up. I'm in complete agreement in that grinding on the lathe is something I really don't like to do. The stone debris falling from the grinding wheel is nasty stuff and can cause accelerated wear to the ways, chuck internals and just about anything else it gets into.

Filing on the lathe is something I've been repeatedly encouraged to do by any number of old timers. It's even become a natural part of my routine when I want to shape a contour in a turning or to fine tune a dimension. The dust from the operation is simply the same metal I've been turning into most excellent grades of swarf, but without the abrasive stone dust grinding would produce. I'm not quite sure why the filings from a small die filer would be any more detrimental than the stuff I'm already producing by hand. Am I missing something elementary here?

I can see the potential for questions of bearing wear, way abuse and even safety issues. Those are things I'm working to take into account as I build this puppy. I've gotten the vibration of the assembly down to near undetectability with a .025 shim, so the spindle bearings are happy. I'm using 6061 aluminum for the base so the soft metal can't beat up the ways and the fit will be snug enough to keep metals from infiltrating beneath it. I'm even putting a commercial grade chip shield in place to act as a chuck guard, as well as adding shielding the small drill chuck with a flange.

I'm working with an eye to durability, usability and keeping all my fingers attached, so I'm definitely open to suggestions. As I said earlier, this thread is about following an unscripted project that will probably see a few dead ends, as well as successes.

Steve
 
Cedge--Just curious here, but to completely eliminate any misalignment woes, why not attach the whole shebang solidly to the ways and use a Lovejoy coupling between the lathe chuck and the input shaft to compensate for any misalignment.

lovejoy l225 cplg (Medium).jpg
 
Brian
To be truthful, The project came about too quickly to have the chance to shop for anything. I've just been rummaging in my parts and pieces drawer for odds and sods to cobble a prototype together. Amazing what one can find hiding in there. I've used Lovejoy couplers for many years and it's an idea I'm very likely to incorporate, as the fine tuning comes into play.

What you're watching right now is a process of thinking things through using real world items instead of my usual digital 3d visualization. I think it's known as "Bodging" in some parts of the world. I'm really having fun seeing where the idea flow and a liberal dose of serendipity will take it.

Steve
 

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