The evolution of a moto-tool stand

Long ago I made a stand for my "Moto-tool" device. These were originally made by the Dremel Company, but nowadays there is a horde of imitations, asiatic and otherwise. Giving credit where credit is due we will call it a Dremel-type tool, or DTT. Dremel offers a huge number of accesories for this tool, and more are available elsewhere. But a DTT is made for hand-holding, and I often find this extremely inconvenient. Especially when I am grinding. So I made a stand for my DTT, which is nothing particularly noteworthy.
Just some scrap wood with a hole big enough to take the DTT. This has given me great service. Drilling the holes to acommodate the DTT is the problem. It can be done with a hole bit if you have one, or with an adjustable circle cutter, which is how I did it. The rear hole is split and held in with a bolt and nut. This is part one of the saga.

Part two was when I made the NanoX table. (It is now the NanoY table.) I did this mostly for the experience, and it's in my posts somewhere. But it moves on one axis. So we have a problem, because it is very difficult to put it just where you want it. Especially for grinding edges on my microforged tools.

Part three when I tried to make a milling vise for the Taig lathe milling attachment. This was a failure. The reason was that the holes were drilled imprecisely. When you are doing metal, you have to work to at least 0.1mm. In wood, 1-2mm will get you by. Another universe, as they say. Can't do it by eye. But I looked at it and thought that if I remade one piece it might work, not as a vise, but as a cross-table for an X-Y table. This is milling machine-speak. A mill is a bit like a drill press with a table on which you put the work. The work is shaped by a rotating cutter. The table can move left and right (X) and back and forth (Y). Milling machines also can move vertically and this, obviously, is Z. Sooo...
Here is the beginning of the thing. At the top, the NanoX table (which has become NanoY now) that I made last year. Below it is the new NanoX table. It has two pieces of square bar, in which a couple of pieces of hardware-store rod about 5mm fit. This came out of the failed Taig milling vise. The white plastic block is a piece of snow machine, found while I walk. I know not its original purpose, but it is some sort of synthetic and very easy to machine, so I drilled holes to fit the rods and tapped the center hole for the feed screw. The NanoY fits right on top of (new) NanoX:
And behold, I have both X and Y movements at the turn of a screw. The real problem in this megilla was scribing the centerline of of the square bar at left. I finally figured it out. I put the thing into the milling attachment of the Taig lathe. This gadget essentially turns the Taig lathe into a mill: X, Y and Z all there. I chucked a scriber in the lathe. With a magnifying glass I registered the scriber at the very bottom of the square bar. The Taig milling attachment has a handwheel that will give you "thous" i.e .001" or .025mm if you wish. Measure your bar with digital calipers. Calculate how many full turns + thou it will take you to get to the halfway point. Hint: 20 turns per inch. So one turn gets you .05". Horrible, I am reduced to RGU. I don't mind it too much. All decimals. It is the fractions to which (not to end a sentence with a preposition) I object.
You do that with the vertical (Z) feed on the Taig. Then with the Y feed (the cross-slide in the lathe incarnation) just draw the scriber across the bar. You have coated the bar with machinist's blue, maybe, but I use a sharpie felt-tip pen. Machinist's blue is hard to find in Alaska. You have a centerline as exact as you can get it. You are limited by the very marginal travel of the Taig cross-slide. Hey, it's a watchmaker's lathe. Don't be too harsh on it. It was made to cut stuff 1cm across. You are demanding 5cm from it. Tough on you. It is a fact of life. No matter what lathe you buy, it will be too small. But it worked. The X-Y feed table, bar a few details, is a done deal.

In machinist-speak, what I did was lay out holes by the coordinate method. Any time you think high school algebra was a waste of time, think of that. In these days of Computer Numerical Control, or CNC, it is even more important that you understand coordinates. If your avocation is poetry, you have no need of them. If you want to make things, then do brush up on coordinate geometry.

And now I have figured out (I think) a feed in Z. I will have made the DTT into a micro-mill. But I haven't done it yet. So I am holding my breath, and my posting, at this point. Stay, as they say, tuned.

Divide and Conquer

Ah, the weekend where we switch from Standard Time to Daylight Savings Time, or DST. Our beneficient congress is under the illusion that it saves energy, whatever that means. It might have been true in 1914 but it certainly is not true now. So it jerks me around for no good reason. I have, therefore, modified the statement in my previous post about politicians in my chilly Hell. The ones that voted for this measure get to shovel snow with a teaspoon.

But I digress, so let's get on with this post. When I did the wheeling and dealing post I showed you a picture of the hubs being drilled up in a dividing gadget. Dividing a circle or cylinder into equal parts is an ever-recurring problem. For instance, I want to divide a wheel hub into N equal parts so I can push spokes into them. Clockmakers, on the other hand, want to cut gear teeth at exactly equal intervals, or their clock won't run. The expensive solution is to purchase a dividing head. This is a worm-and- gear gadget that allows all kinds of divisions. But do I really need a dividing head? Not really. That old clockmaker's standby, the direct division plate, would do me just fine. Simply a circle with holes drilled into it.

So this weekend I took time out from secret project and improved the device. Here's the first improvement:
We have acquired a direct dividing wheel. This is a plastic wheel with 12 slots-- from where I have no idea, I found it on the floor and said "hey! a pre-made dividing wheel!" It also has a three-step pulley on it. Well. Maybe three, a piece broke off when I was parting it off. Parting off is such sweet sorrow, and far more experienced turners than I have come to grief with it. The super-useful plastic calipers ( fifty cents, part of a set, reads out to 0.1mm and if your eyes are good, to 0.05) are 80mm between divisions -- the whole divider is tiny.

You will note the suspicious resemblance to a lathe. In my mind I thought of that when I cobbled it up, and believe me "cobbled" is the operative word. I have it in mind I could drive it with a bow if I wanted. If so we'd need a tool rest, wouldn't we?
Here is my trusty third hand acting as a toolrest, and a pencil acting as a turning tool. The tool has also acquired a much sturdier base and has been dadoed into the same. A posed picture, of course. A wine cork is standing in as a turned piece. But if I can divide a wine cork, or even turn it, the possibilities are endless.

OK, but how do you hold the thing while you are dividing it? And what are you going to do about a tool rest? So today's steps are to rig a tool rest and put in a detent. A detent, in machinery-speak, is a device to hold something still.
I never throw pieces of steel away, especially saw blades, and there is a piece of broken coping saw blade in a hole, fixed in (I blush to admit) with plastic wood. It has a cross-pin put into it which providentially is just the right diameter to engage the slot in the divider. I will have to make a pullback handle of some sort for it. You will note, also, a block of wood fixed to the side of the base. This will support the tool rest.

You will also note the board the whole thing is sitting on. This is my work board. I use it for all my miniature work. It was originally salvaged from a huge dump of offcuts in the village. It is rock-hard, I suspect maple but it might be some asiatic wood. Anyway, today I made an Aluminum clamp thingy and fixed nano-vise to it.
I made the front-holder bracket before, also out of Ally. Aluminum (or Aluminium, as the british say) is very good for this sort of stuff. Much easier to work than steel, and much stronger than wood. One of the problems with NanoVise was that the screw pulled the brass rods right out of the vise! Never underestimate the power of the screw. I could epoxy the rods. I suppose someday I will but for now this works fine. And now I must return to secret project.

The NanoVise

Recently I began carving a bull moose out of Ben Hunt's book on whittling. Alas, out of print; it sometimes turns up in used bookstores (which is where I got my copy). The only difficult part is Moosie's antlers. They are less than 20 mm longways. I have a real specimen to copy (see some previous post last year!) The real problem was holding the blasted things as I carved them. I nearly gouged my fingers off doing it. Couldn't put an antler in the metal vise; it would have crushed them or at least scratched them. I needed a very small vise to hold very small carvings.

Now a vise is not all that different from the Nano X-table of the previous post. This one had to be made of wood, to avoid scratches on carvings. Instead of a table, the moveable jaw of the vise is substituted. A manic session with miniature Dozuki and Ryoba saws, and a trip to the drill press, and Nano Vise came to life:
The NanoVise has a pair of fixed pieces (right and left) and a movable piece, the jaw part. This jaw, in the center of the above pic, slides on ways made out of brass rod. I bought the brass rod, I must admit; very difficult to find it thrown away, especially in Alaska midwinter. Buck and a half, I think. It is very difficult to drill the holes for both NanoX-table and NanoVise. It has to line up in two directions.
The holes have to be the same distance apart, but they also have to line up horizontally. I solved the first problem by making a drilling template out of scrap metal. Never throw away anything! The horizontal problem is only partially solved. If you had a very long drill of the proper size, and a great big drill press, it would be easy. So we impro-vised. Ouch.

The next job is to turn the feed screw (another found long bolt, 8-32 RGU). You have already seen this in the NanoX-table post. When it came to collars for the feed screw, however, I wound up microforging the collars out of brads. Much better than the plastic on the Xtable, but a lot more work, too.
Here NanoVise is seen holding Anton the Fiddler, a protagonist in the upcoming Tyrolean Music Tableau, date of release uncertain. I cross-drilled the feed screw and stuck a brad through it to act as a vise handle. I used a bead from a found plastic necklace to keep the brad in its proper place. Expect to see lots of future appearances of NanoVise. The feed nut was epoxied to the moving jaw, as in NanoX-table.

I am really glad I spent a few days making this vise. It has already paid back its price in utility. Miniature carving demands miniature fixtures. There are a few problems with NanoVise. If you are not careful the pressure of the jaws will force the ways right out of their holes. This, of course, is why version 2.0 was invented in the first place. So stay tuned. And for those who dote on measurements, NanoVise is 83 mm long. (I was trying for 80, but you can't win them all).

The Nano-Xtable

We have now concluded the Christmas presents section of this program and can get back to our regularly scheduled projects.

I have my moto-tool (which is not a Dremel (tm)) mounted in a homemade stand. There are pictures of it all over the blog so I won't repeat. All well and good, but I need a support when I do grinding. I used wooden blocks for a while. They are difficult to clamp, so freehand is just about as good. But an idea came to me, inspired by David Wingrove's books on car modeling. I could make an X-Y table! Then I could do miniature milling with the moto-tool! An X-Y table is a flat piece (the table) that slides on ways in two directions: X and Y. It is turned by screws. So, depending on the accuracy of your srews, you can adjust the table any way you like. I have one, actually, but it is much too big for what I want. Now X-Y movement is what we engineers call "two degrees of freedom." So I thought I would warm up by making a table with but one degree of freedom, an X-table. And I did.
This is the table in its current incarnation, all 85mm of it. Every piece except the ways and bolts was found material from my summer walks. Probably fell off snow machines. Good. The table is a block of aluminum alloy with two grooves cut in it. Providentially the grooves are a perfect fit for the aluminum ways, bought at Lowe's for $1.59 or similiarly low price, and I still have lots left. As you turn the screw, the table moves majestically across the ways. The screw is another objet trouvé -- amazing what people throw away. The white supports are some very dense plastic. I hope it was crucial to the snow machine's operation, said he spitefully. So now on to building it. The first thing I had to do was cut the rabbet (or rebate, a much better word for it) in the plastic supports.
I am using Trusty Taig, the lathe. Thanks to Model Engineering magazine, I find that chucking the end mill right into the 3-jaw chuck gives very nice results. I don't have big enough collets to take 12mm end mills. The plastic, whatever it is, machines beautifully. And note my milling table. This is another find, a right-angle piece of ally alloy that I screwed right down into the primitive vise on the Taig milling attachment. (The Taig atachment is beautiful, but has no vise to speak of. They will sell you one for over fifty bucks. Pah.) I can then clamp to the milling table, as in the picture. I did not make a pass over the bottom of the piece. I will pay for that omission.

The next thing was the feed screw. This is the screw that carries the table (that JRC built). It took some time for me to figure out the obvious. Usually you turn a screw, it moves, right? But this is exactly the opposite. You do not want the screw to move. It has to stay in place. That way, the nut (attached to the table) will move instead. So how do we do this? By removing the thread from the screw where it goes through the support and then securing it with collars. First, a straight turning job to remove threads:
Actually, A groove would be enough, one at each end. But I took off the threads all the way, which leaves lots of room to put in collars. The big-leaguers use circlips, spring-steel circular clips which are guaranteed to reach earth orbit if you don't handle them correctly. Ping! No more circlip. Don't have any. So I cut collars from some of the stiff plastic that came with my brand-new moto-tool packing.
The collars are the white, more-or-less round things at the ends of the screw. Any shape would so, really. Cut them, drill them so's they fit the turned-down section of the screw; split them, force them in. It works! Note the nut attached to the table with JB-Weld, marvellous gunk that sticks to anything. So I can "weld" a steel nut to an aluminum block. Can't do that with your MiG outfit.

I keep looking at this thing and wondering if somewhow I can con it out of another degree of freedom. Then I'd have a true Nano XY-table. Maybe I can. We will see. Not much room left to maneuver. Can't foul the feed screw!

On the net, there is a wonderful article (or was) called "The Fonly Lathe," written by some model railroaders who needed a lathe. They adapted a moto-tool into a lathe. If you google on fonly lathe you should find it. I am slowly working my way up to a Fonly mill. Fonly lathe, of course, is short for "if only I had a lathe."

The ultimate table, Nirvana, is an XYZ-table. Three full degrees of freedom. Hey, maybe I could do X-Z... hmmm. Got to think about this.