tools02-good

More Tools For Slot Car Motor Building

Good Things to Have

Armature Blank, Finish Bore Size(s) - Also referred to as a "slug," this is the cylindrical aluminum (or steel, for some uses) shaft-mounted "spacer" used to either set or check magnet bore diameter (a discussion of how and when to use this tool for those purposes can be found in the "Steps" section). It can also be used in conjunction with the brush hood alignment tool for setting endbell hardware, and, as you'll note in that part of the "Emergency" section, is invaluable for most can bearing/bushing replacement jobs. Some notes: the point of this tool has to do with the precision of a) its true diameter, and b) its concentricity to the shaft. If the diameter is not exactly the dimension you need it to be, and if the shaft is not precisely centered within the body of the blank, all the measurements and references you make from the shaft of the tool will be off to that same (or greater) degree of error. Since there are two basic ways to make one of these things, both of those dimensions can vary to some degree based on the way the manufacturer produces them. The worst (and, of course, easiest and cheapest) way is to turn the body to final diameter first, then drill a shaft hole for a press-fit. The better (and more expensive) way is to rough-turn the body close to final size, insert the shaft, then turn the final body diameter between centers for maximum accuracy in all planes of measurement. At $5-$7 a pop from most suppliers, which way do you think most of them (or, at least, the ones I've seen) do it? Uh huh.

When I'm not in a truly masochistic mood, I buy them (supplied by Koford and others) oversize (e.g., .530") and turn them to the diameter I need. This allows me more than a few magic moments when I look at what the nominal size on the packaging says compared to what the micrometer and dial indicator on the actual piece are telling me. When I do feel masochistic, I make my own using drill rod and steel or aluminum rod stock. In slot car racing, I figure this may be second only to making your own tires in the time-spent/wasted vs. end-product department, but what the heck, like the saying goes, "anything worth doing is worth doing to excess," right?

Block, Sanding, 320 grit & 600 grit - These are actually some things you can make yourself in about 3 minutes. Take a piece of something like 1x2 wood (its actual finished dimension is not really important) and cut it into a few pieces about 6" long. If you feel like it (and have access to the tools), you can dress the ends at 90º to the sides and (relatively) flatten one or both large sides on a belt sander (tidy but not mandatory). Then simply stick a partial sheet of self-adhesive sandpaper of your choice of grits to one (or more) side and trim the edges as necessary. Remember that these are not absolutely flat surfaces, so never treat them as if they are. You'll quickly discover a number of uses for these things, like cleaning up surfaces and edges, finishing work on can ends, and delicate solder removal work around some fillets like the can bushing. They're cheap, renewable, and offer additional uses in the slot car building realm beyond motors. Try one and see.

Compass, Magnetic - The quickest and easiest way to check magnet polarity in or out of the can. Just make sure that you and the person who "zaps" your magnets are on the same page regarding what "positive/negative" and "north/south" poles mean (a longer discussion of polarity issues can be found in the "Steps" section). This
may be the only tool on any of these lists that can actually be found in a box of Cracker-Jack.

Drill, Set, 1/16" - 1/2" - This is close to a judgement call. There are a number of drill sizes that are actually useful in building slot car motors, but they sure as heck don't comprise anything close to a set. But, hey, the subtitle says "Good Things to Have," not "You'll Die Without Them," right? Resist the temptation to snag one of these fractional sets from your local Boat People Tool Store 'cause the price is right. Many times, the drills aren't. Not to say, mind you, that some people's definition of "high-speed steel" seems to mean 2 to 3 rpm. Drills, like most other tools, represent an investment that should be amortized over time and multiple uses. Some things that look like drills, it turns out, won't actually drill holes in some normal materials more than once or twice, if you consider mild steel and aluminum to be normal materials (I do). Buy a name brand set (or buy a holder and assemble a set bit by bit - quasi-intentional pun - as you can afford them, eventually more expensive but momentarily less painful) from a reputable source. If you know how (or can quickly learn) to identify what you're looking for, this is another good item for your garage sale shopping list. Make friends with someone who owns a good drill sharpener, and remember that you're not likely to be able to resharpen drills of about 1/8" or less. And how, you might ask, does one use big, dumb drills on a slot car motor? When you discover that a normal countersink is too big to fit in a C-can when you want to deburr and relieve the internal can end to fit a bushing fillet, you'll figure out why having a sharp 3/8" drill handy is not a bad idea. Or when you finally decide that you'd actually like to see the bushing on some endbells so that you can lubricate it, not the endbell.

Drill Motor, Cordless - Repeat this sentence 10 or 15 times: "I will not use my motor tool to hone magnets." Done yet? Liar. This tool doesn't have to be great; it just has to work. Most cordless drills (we can dispense with the proper terminology) will work quite well, provided a) the drill chuck is reasonably accurate (most are), b) the drill has sufficient torque to easily accomplish the task of honing magnets at a reasonable speed (most do, and your motor tool doesn't), and c) the drill has a battery charge life that is long enough at this work-load level to allow you to accomplish what you sometimes need to do (some, surprisingly, don't). Mid-level units from most any recognizable manufacturer (and some lower-level units from better manufacturers) will fit the bill. If you don't already own one that can be pressed into service, expect to pay about $55 to $75 for a decent drill with the specs you need. Added benefit: this is a pretty generic purchase that, like a lot of other tools on all these lists, has uses beyond the slot car world. Take that into consideration if you're buying one for the first time.

Dye/Fluid, Layout ("Machinists Blue") - The stuff that lets you know what's still there after you try to make it go away. Alternately, the stuff that lets you scribe lines you can actually see on shiny things. Alternately, blue or red arm "dye" (you didn't think that arm manufacturers developed their own line of paints, too, did you?). A form of thin, translucent lacquer, the most popular brands of which are Dykem and Precision Blue, you can buy a large can for $3 to $5 at larger hardware stores, which, for most slot car motor uses, should last 20 to 25 lifetimes (if it didn't occasionally turn to lacquer-based, useless **** in the can after a few years). I have both, but use the blue arm-dye bottle more frequently because it takes up less space on the bench.

Glove(s), High-Temp, Kevlar - Skip the name brands on this one (NASCAR and NHRA teams have a
budget that's generally a little higher that ours) and find a source for some generic Kevlar, non-slip gloves. Why? Because at some point in motor building, not to mention the rest of this hobby, you're going to have to handle objects that are actually hot enough to burn you. While they don't really make you impervious to pain (even Kevlar has temp limits), they certainly help. You should be able to find them, somewhere, for about $10-$12 a pair. Other types of gloves will work (as I'm sure you already know), but most have a tendency to be bigger, bulkier, and to transmit heat far more easily than the Kevlar variety.

Hammer, Bodyman's, Flat-Face - Some times, you just have to beat on stuff (e.g., can straightening). You don't, however, have to beat very hard. While the weight is about right, the face of a tack hammer is too small. The same is true for a ball-peen hammer of the proper mass. A bodyman's' hammer with a 1 to 1-1/4" flat face works best for me on these jobs. Once you own one, you can ask a body guy what he uses the other end for.

Hone, Brush Face, Diamond - I prefer these tools to their plain-steel cousins simply because they work faster, last longer, and seem to load up less. If cost is a serious object, the steel versions made by Koford and others will do the job for you, given the above limitations. For extensive work, however, I think the diamond hones are more useful. I own them in 3 different diameters, none of which (of course) usually ever correctly matches the diameter of the commutator the brushes are going to be used on (that's probably one of the reasons God let us figure out what breaking-in a motor actually did). There is a school of motor-building thought that says "To hell with the honing - just put new ones in and let 'er rip!" There is also a school that suggests rehoning the old brushes ever time you touch the motor (and you probably already know about the school that mandates new, honed brushes every rebuild or disassembly). Beats me. Many far wiser than I have even more ways to approach this topic, so I just try to pay attention, experiment, and note what works (and, maybe, why). I suggest you do likewise, remembering that what you're looking for should offer better results than the method you're currently using, not simply a different way to end up with the same result.

Hone, Brush Hood, Diamond - This is the more expensive and useful version of the brush hood alignment tool discussed in Basic Tools. Since all brush hardware I'm familiar with is stamped and formed, the hardware has a tendency to vary somewhat in configuration. Additionally, not all hardware from all manufacturers measures the same when it comes to brush mounting. Measure the width and height of a selection of brushes (using that spiffy set of calipers you own), then measure the installed dimensions of the brush hood. What you'll find is that most appear, at best, "tight," while some, depending on the manufacturer, are absurdly loose (I don't know about you, but the idea of a brush loose enough in a hood to actually rattle around doesn't really appeal to me. But what do I know, right?).

The hood hone allows you to clean up, smooth out, and deburr the inner surfaces of the hood that the brush actually rides on. Since the honing has to be done by hand without an accurate center reference, and since you're doing it to copper, brass (yuck), or plated aluminum (double yuck), this is another of those circumstances where more is absolutely not better. Take it easy with the pressure applied. These hones are generally coated on two contiguous sides (in an "L" relationship), so they have to be rotated 180º to cut the two other surfaces. Once the hoods have been aligned, cleaned up, and smoothed out, there isn't any need to remove more material. It may be silly, but I use what I call a "drop test." If a new, uncut brush can be inserted on one side and drop through both hoods and the endbell on its way out the other hood, it's smooth enough for me.

Hone, Brush Shunt Relief, Diamond - If you get tired of trying to use the flattened edge of a broken grinding disk as a tool for cutting reliefs for shunt wires (or hate your finger tips sufficiently to try grinding the relief with a disk in your motor tool), try this little honey. Another of the diamond-coated tool family from our friends at Magnehone, this basically consists of a coated wire and a holder. A few passes and it's done. Or ruined. Brush material is reasonably soft, so a diamond tool cuts it quickly. Practice on some dead parts before you turn yourself loose on the good stuff. This will also allow you to figure out how wide and deep you need to cut the relief to properly capture and retain both the shunt wire you use and the spring end. An added benefit of the diamond tool is that it cuts a rounded groove, diminishing some of the possibilities of cracking off the ears of a cut brush by eliminating two possible stress fracture routes. If you absolutely have to have a square-cornered slot, you can put the stress risers back in by using the flat edge of that grinding disk.

Hone, Magnet, Sizing Diameter(s), Diamond - See Below.

Hone, Magnet, Finishing Diameter, Diamond - I've lumped these two (or more) tools together because I'm firmly convinced that magnet honing should be performed as a multi-step process; that is, gradually enlarging the magnet bore towards the desired finished size in small increments of material removal. Can you cut loose with one hone of the desired size and end up with (mostly) the bore you want? Yes, and lots of people do. I did, too, until I thought about it. Installing the oversize magnets currently available in a C-can frequently gives you an internal magnet dimension as small as .460"-.465" (I have actually removed some material in some setups using a .460" hone as a "pilot" grinder). If your intended finished size is in the neighborhood of .520" or so for a C-can and the smallest internal measurement is, say, .470", you are about to ask that hone to remove .050" worth of material, or up to .025" per side, in one pass. In my opinion, that's a lot of work for a small-diameter, low to moderate-speed, diamond-coated tool with unknown bonding material to do. Not to mention the glue and/or knurl which retains it on the shaft or the time/temperature problem if you're not grinding in water. I use a sequence something like this: .460" or .470"/.480"/.490" or .495"/.500" or .505"/.510" or .515"/finish size. Wretched excess, perhaps, but no individual hone is overworked and each honing operation goes pretty quickly.

There's absolutely no doubt that magnet hones are some of the most expensive individual tools the average slot racing motor builder will think about buying. I counted, and I own 23 of the suckers, including a lot of custom sizes that made sense at some point, indicating that I should really have paid more attention to what I was buying (and that my life must be incredibly shallow to devote that much money to stupid **** like this). Before you spring the bucks, think about the following: while they may be priced similarly, not all hones are created equal. I look for those with a shaft length sufficient to be used from either side of the hone face, capable of full travel through the magnets, without the chuck of the drill hitting one end or the other. Not all hones are so constructed. Some actually have "handy" little hand knobs for "precision" honing. I'm sure many serious and/or "pro" motor builders enlarge the bores .001" at a time during experimentation, and use the knobs. Good for them. I have countless other ways to get blisters on my fingertips while boring myself witless, so I cut to the chase and use a drill at very low speed. As for cutting more than that amount by hand? I have some idea how long it took thousands of people to construct the great pyramids of Egypt, and I have no desire to be buried in a C-can anyhow. Another thing to consider is forming what, for lack of a better term, you might consider a "hone co-op," where a number of people each buy a different but utilitarian hone size, then trade back and forth when building motors. Worth a try.

A word about honing in water: I've come full circle on this deal, starting with water, going to "dry" honing, then eventually back to water. At the speeds and material-removal rates I deal with, heat was not a problem; even if it had become one, the temperatures generated didn't threaten my magnet epoxy bond, and I rezap all my motors after construction anyhow. Lubrication and ease of honing may be improved by doing the work in a coolant, but not to a degree that makes a dry method irrelevant. No, I went back to honing under water solely for magnet dust control. Honing in or under a fluid has a tendency to restrict the distance the ground magnet debris gets flung. Think about that a minute.

Bushings are pretty forgiving of particle contamination, but ball bearings tend to commit ritual seppuku in the presence of particles. Hard particles. Hard magnetic particles. Well, it makes me nervous, anyhow. Nothing will actually stop some debris from migrating to your precious bearings, but the water has a tendency to restrict it to a worthwhile degree. I have found no useful difference between running water and a large pan or pot, and the latter is usually easier to accomplish in places people normally build slot car motors. By the way, you can resist the temptation to collect the sludge-like magnet residue and mix it with your magnet epoxy for some sort of magic fix. If your armature doesn't give a **** what the gauss reading on the outside of the can is, maybe you shouldn't either. I would caution you to develop an accurate touch or rotation sense about whether a bearing is clean and free of contamination. The easiest way to do this may be to take a new bearing, insert the shaft of an arm in it, and slowly turn it back and forth while applying a slight side load to the bearing. In a new bearing, you'll feel the increased drag from the side load, but shouldn't feel anything else. A little bit of experience here will go a long way. Make certain to completely clean the bearings in both the endbell and the can after each honing step before you proceed to the next one (or final cleaning and assembly). If you feel any imperfection or suspect that something is still in the bearing, keep cleaning it until what you felt is no longer present, and the bearing spins and feels like a new one. Some of the methods I use to clean motor bearings are in the "Steps" section, but this is one area where time and available equipment pretty much dictate your choices.

Lamp, Articulating, 60-75w - I've spent a vast majority of my life building models of one sort or another, and working with little bits and pieces. One of my many conclusions is that it may be impossible to have too much illumination on the subjects I'm working on. Too much glare, yes. Too much light? Probably not. And yes, I'm familiar with scientific studies that have calculated the proper number of lumens per square foot for most work activities. I've come to the understanding that no matter what my vision can actually resolve or focus on, it's the contrast between objects and their background that permits me to see it clearly. No matter how slight, sometimes it's the difference in shadow detail that helps your mind identify the thickness difference between a .003" and a .005 arm spacer lying flat on your bench or work table. I haven't found anything more cost-effective for decent illumination than a collection of inexpensive articulating "arm" lamps and normal incandescent bulbs (and I've tried all manner of diffused, indirect, and fluorescent types). Your needs may vary somewhat, but a few of these will suffice for most building activities. For what you want to use them for, the $10-or-so items at your local home center or larger hardware outlet are fine. Experiment with the bulb wattage, angles of illumination, and distance from work until you find what works best for you. As an added benefit, with a little thought and a bit of work, you can adapt their "universal" surface mounts to fit the edge or side of your slot box, allowing you to have some extra light at the track when you need it.

Notebook, Spiral-Bound, Small - Actually, get 2 of these, with different color covers. Keep one on your bench or building area, and use it to log everything you do to a motor while building it. Give each motor its own page to start with (front and back), and enter every significant component and dimension that makes that motor unique. As an example, topics could include: motor number/date built/endbell & bearing/bushing type/hardware type/can & can bearing/bushing type/magnet manufacturer/magnet final hone diameter/preliminary gauss readings/armature manufacturer, group, diameter, timing, meter readings if done, an so on. Don't forget to clearly identify the motor via some permanent number or marking on the can (most markings by "permanent" pens last until the second or third time you handle the motor - engrave your i.d. on them). Indicate the first application (car) the motor is used in, and its initial gearing. Thereafter, use that page to record rebuilds, modifications, arm substitutions, spring replacements, and any other significant change to the motor that in any way could alter its level of performance. What you're doing here is building the foundation for a - and may God forgive us - database of information.

You know all those internal trailer shots they use during TV coverage of major NHRA and NASCAR races, where the driver and/or crew chief are standing there, peering at computer screens? Those screens contain data, information, or, using the technical name, stuff. What they're trying to do is integrate what the car is telling them, via telemetry and performance, with what they already know. And what they already know is past performance, components, and configuration, expressed as entries in their database. No matter what your local computer gerbil may try to convince you, a database is simply the basic elements of (a) history, sorted out into bite-sized chunks. Done properly, it tells you what, where, when, and under what conditions something happened; it doesn't tell you why or how. Which is why those guys are staring at the screen. They're trying to come up with their best guess as to what to do fix/improve the performance of the car based on what they already know. You'll note that they don't rely exclusively on their collective memories here, and neither should you.

That other notebook, the one with the different color cover, is the one you keep in a back or apron pocket, ready to record all the rest of the information you collect during testing, tuning, and competition. It's the other part of your database or information history. Things like track temperature, gluing methods, spoiler angles, and the like (in addition to the usual e.t., speed, and 60-foot times you may already keep track of). You want to know everything that has a measurable affect on how the car performs no matter what the motor does. It may be a major pain to do, but I look at it this way: given equal budgets and components, the person who knows more about the way his cars perform, and under what conditions, generally does better than someone who doesn't. Doesn't cost much either, other than time and effort. Your choice, though.

Oven, Toaster - A kitchen oven is overkill and a waste of electricity. For curing and heating things that need to be cured and/or heated, a toaster oven is great. I have several, all purchased at garage sales, and the most expensive one cost $7. Why more than one? Sometimes you work on things in batches, and some of them may require a different time/temperature condition than others. Just one will suffice for most needs. Spend some time calibrating it with the oven thermometer (below) you're going to buy, because the normal toaster oven heat settings run along the lines of "sort of hot/hot/real hot/too hot." Also great for flaming those beef n' bean burrito snacks when you're too lazy to make it back to the kitchen. Toaster oven note: if the word "preheat" means nothing to you, ask your wife/significant other/mom what the recipe people mean when they use it, and apply the concept to your dealings with a toaster oven, particularly with higher-temperature work.

Pliers, Assorted (Needle-Nose, Small, Needle-Nose, Medium, Parallel-Jaw, Round-Nose) - There's a reason they make all those different styles of pliers. Honest. For holding, bending, twisting, and general forming, somewhere there's a pair of pliers to do exactly what you need to do. Before you go out and buy 30 pair, start with a few basics. Some good relatively small (4-5") and medium (6-7") needle-nose pliers will do 99% of what you need to do with slot car motors. As the strength of the pliers is roughly proportional to their size and construction, figure out what jobs require what strength before abusing a set into uselessness (hint: when you see the jaws moving before the piece you're trying to bend does, you probably need a heftier pair). Don't buy any with a nose small enough to puncture your skin; at some point, you probably will, either before or during the job that breaks one of the tips off. Unless you have a need for jewelers' pliers, a tip width of about 3/32-1/8" is normally small enough to do most everything you need on a slot car motor (and, for that matter, on a slot car).

When it comes to more specialized jobs, my favorite pair is a set of articulated parallel-jaw pliers. Slightly larger than a normal paper punch, these pliers apply reasonably even pressure along their jaws via an articulation linkage (hence, the parallel part), will bend or form anything connected to slot car work, have a grooved pass-through feature that allows long rod work to be run through the length of the pliers, and feature an external set of cutting faces for wire and rod work. I have a lot of cutters I've collected over the years, and these pliers work better for that function than any of them. Downside? They are not cheap. The ones I have were made in England and cost about $30-$35 some years ago, and I don't imagine that they (or ones of equivalent quality from some other source) are any cheaper now. For that other 1% of motor jobs, round-nose pliers (imagine a pair of needle-nose done as two long, tapering cones) work well for pre-forming wire and unwinding/rewinding/altering motor springs. Remember, however, that they are not as strong as the equivalent size of needle-nose pliers. For most of these purchases, I'd shop name-brand exclusively, with emphasis on a source that will be around for some time, and that won't forget what "lifetime warranty" means. Avoid the temptation to buy on the cheap; with these kinds of tools, you generally do get what you pay for. If you feel lucky, garage sales occasionally offer up some bargains.

Power Supply, DC, Regulated, w. Volt/Amp Meters - At some point in your motor-building career, the necessity of owning one or more of these will become apparent. What will not be so apparent, however, is which one to own. New ones? My opinion: if I can't blow up a cobalt open motor on it, it isn't worth owning. I don't care how neat it is, how small or (mostly) how big it is, how many dials, lights, meters, or controls it has. If one power supply cannot provide full voltage and sufficient amperage for every sort of motor I may work on, what's the point of having it? Granted, I rarely put a cobalt motor on the clips, turn the dial to Nuclear Meltdown, and flip the power switch on just to see how far the parts will fly. But I do like to run most motors in for a time in their final chassis installation position to seat in gear wear and the like. Some power supplies won't pull that load very well above about 2 - 4 amps, and I don't have a lot of motors that pull less than that, even with no load (except, of course, for the truly wonderful 16D family of fine pieces of... ahem, yes, those motors).

Used ones? I don't know of any good, cheap new ones. I don't even know of any bad, cheap new ones. So, should you come across one of those "I hate this stuff! Buy my box for X dollars." kind of situations, and the box contains a working power supply of a brand or type that someone on this continent has heard of, and it works, let your conscience and your wallet be your guide. At least in basic C-can building, some is better than none. Figure out what sort of overload and/or short protection it has; if it's fused, buy spares immediately. I once watched as my power supply repeatedly blew fuses when one of my very fast friends hooked up his AA/FC to it. Three tries, three fuses, but the motor showed no binds and measured with no shorts. So, scratching our heads, he ran the car. Fastest reverse pass I ever saw in my life, right back into a wall. Guess those little cobalt thingies really pull a lot of amps when you ask them to run 25º or so retarded.

Reamer, Chucking, .078" Nominal - Before you rush out and buy one of these for bushing work, you get to make some decisions: does the manufacturer of the arms you're messing with use a nominal 5/64" shaft (.078125") or a nominal 2 mm shaft (.078740"), and if so, how much do the shafts vary from arm to arm? While the basic difference (.000615") may not seem like a significant amount to you, it is to a bushing motor trying to turn a gajillion rpm. As the name implies, these reamers were designed to be chucked in a lathe to precision-size a hole (most commonly while the bit with the hole to be reamed is rotating in the lathe chuck while the tool is held stationary, but occasionally the other way around, as well). When used by hand in a pin vise, they a) make real machinists shudder, and b) are nowhere near as accurate. Fine. Under most circumstances where you might press one into service (making bushing holes that are too small closer to the proper size), they're almost always more precise than a drill. Given the likely margin of error, I use a 5/64" reamer for most resizing jobs, and a .007800 (undersize) reamer with a dummy lapping-in shaft for jobs with a high paranoia level. Most likely functionally useless, but reassuring nonetheless. Skip the overkill part and stick with the 5/64" unit to start with. Straight-flute (recommended) or spiral-flute reamers this size should run between $6 and $8.

Note: reamers, carbide tools, and other serious machine-shop bits you may have need of can sometimes be hard to find; snag an Enco Manufacturing or Rutland Tool & Supply catalog from one of your overtooled friends and get on their respective mailing lists for general and sale catalogs. Their prices aren't awful, either.

Reamer, Tapered, Utility - The quick and dirty way of making holes bigger. Nominally self-centering (yea, sure), tapered reamers make short work of enlarging can and endbell bushing/bearing holes. So short, in fact, that with very little work you can easily end up with a hole that nothing will fit in. "Judicious use" is the appropriate phrase here. The end product (hole) of a tapered reamer almost always requires finishing, no matter what material you're using it in (some degree of deburring will usually be necessary). Remember that while incredibly handy, one of these reamers is not truly a precision tool, and the size and location of your end result is strongly affected by pressure and angle. Also recall that the tool is tapered; the entrance side of the hole it creates is perceptibly larger than the exit side.

Scissors - Gee, you have to have a pair of decent scissors lying around that you can dedicate (or at least divert) to slot car motor work, don't you? Something that will cut and trim shunt wire, and not just bend it over the blade? A pair that can also be used to trim braid? Get some. Like this comes as a surprise: good scissors are not cheap, but scissors that will work for these purposes are where you find them. Don't expect a pair pressed into this service to a decent job on lexan or other materials after a while. As for using side cutters: you'll note that other than a reference in the pliers section, cutters are absent from any of the motor lists. I have a lot of them, including a few truly weird pair, and none that I own will do anywhere near the neat and clean cutting job on this stuff that a decent pair of scissors will.

Scotchbrite, Coarse, Medium, & Fine - Some of the neatest stuff known to man, these industrial grades (Grey, brown, and white or light tan in color) are cousins to the ubiquitous green scouring pads you probably have sitting on or near your kitchen sink. Available at reasonable prices at better hardware and auto parts/body stores, Scotchbrite will do almost everything medium-to-fine wet/dry sandpaper will do while lasting longer. The finest grade is outstanding for the final polishing of things that need to be, well, final-polished. I'm actually afraid to mention some of the things I use this stuff on, for fear you'll think I'm nuts. Suffice it to say that I use it - mostly the brown and white varieties - constantly. Try some and I think you'll see what I mean.

Screwdriver, Jewelers', Set - This is one circumstance where you probably can get by with something from our good friends at the Boat People Tool Store. Just don't expect too much (except a low price). Should you care to step up to the plate for a serious set or individual tool, small drivers manufactured by the West German company Wiha have handles that are actually usable, virtually indestructible blades, and a palm-pivot that works (which is to say, they don't bore a hole in your hand when you use them). You may find them in better hobby shops (I did), and while they're not outrageously expensive, they ain't cheap, either. One size, however, is absolutely perfect in width and thickness for those nasty little steel and aluminum 0-80 screws cobalt motor manufacturers love so dearly and motor builders hate so much. I'd think that a cheap set of generic jewelers' drivers and one or two selected decent ones for specific purposes would do for most builders.

Scribe, Tungsten-Carbide/Diamond - For those times when you need to make permanent or semi-permanent marks on metal (or anything softer, for that matter), a tungsten-carbide or diamond-tipped scribing tool is a good first choice. Normal or "tool" steel scribers, while acceptable for plastics and acrylics (and wood, I might add, should you be using that material somewhere in your slot car building), wear too rapidly for my taste. A number of manufacturers, e.g., General, etc., provide them in pen-like holders, complete with the pocket clip (for the machinist's version of the Nerd Pack, I presume). Some come with magnets at the tip. Be my guest, but I cut the magnets off (see "Tool, Demagnetizing," below). Not very expensive, and useful for engraving top and bottom marks, polarity indications, brush indexing marks, and finished magnet bore size on a can. I hesitate to recommend an electric engraving pen, even though I have and use one, because after a gajillion years, I still haven't figured out how to make consistently-sized, neat and legible letters and numbers with the thing. Your talents, will, in all likelihood, exceed mine, so feel free to give one a try. What an electric pen won't do that a scribe will, however, is indicate neat, straight lines on a dykemed/blued surface for measurement or as a cutting/grinding-limit mark. If your funds (or interest) is limited, buy the scriber; if you're in a spending mood, buy both.

The engraving pen will allow you to wile away the idle hours engraving your name and social security number on tools and everything else you own that isn't bolted down - and some stuff that is - as a theft deterrent. Don't blame me for the elimination of privacy, etc., involved with the name and SS number business; both the police and my insurance company asked me if all the tools in a massive box that was stolen from my truck had both on each tool. They didn't. Now they do.

Square, Machinist's, 4" - You don't need a great one (they cost about $80), but you sure can use a pretty good one (which, for our purposes, start at about $10). Like a lot of the tools on these lists, a machinist's square is used to make sure that something that's supposed to be a certain way actually is that way. In this case, that turns out to be things with an external 90º relationship with one another, such as the sides, bushing end, and endbell mounting tabs of a motor can or strap. Added benefits: the blades of a machinist's square are also extremely useful for providing a known flat surface for zeroing, advancing, or retarding endbell hardware (see the appropriate section of "Steps"), and a square is hard to beat for referencing the position of chassis bits against a known center line or establishing right angles on wheelie bar assemblies. Not, mind you, that this is a chassis section; just that at the end of the drill, you have to put the motor in something, right?

Tap, 0-80 Pitch - Sooner or later, you're going to need one (or more) of these when/if you work on certain brands of C-cans and just about any cobalt motors. They're small, fragile, and a pain to hold and position properly. Suck it up, because there's no way around them in most circumstances. A larger-capacity pin vice (see above) will make it easier, but nothing will make tapping holes this size fun. Remember that the proper hole diameter to start a 0-80 tap is 3/64" (.046875), so stripped thread repair requires either some creativity or - groan - drilling and retapping to the next larger size ( the most commonly available of which is 1-72, using a #53 pilot drill) that offers full thread engagement. When these break off in a work piece, you need to be a trifle lucky to salvage the part. While you can find them from some sources with a body size approximately the same diameter as the thread-cutting portion, taps this small are a little easier to hold and use (but also a little easier to break) when the thread-cutting portion is necked-down slightly from the body. General and others usually have them on their jobber racks. If you need one, don't forget to buy an appropriately-sized drill to go with it - a thoughtful combo occasionally available from your track, as well.

Thermometer, Oven, 0-600º F - The device that allows you to calibrate your toaster oven (or, when no one is looking, the kitchen oven) to more accurate settings. Maybe. I suspect that no one in the kitchen thermometer business worries very much about a +/- 5º F variance. I usually don't, either (although I do calibrate mine using a digital pyrometer found in the "Exotic..." section, probably a serious waste of time). If you use one that has a vertical mounting feature, you'll find it's a little easier to see through the small window of the toaster oven.

Tool, Brush Radius ("Turtle") - One of Magnehone's brighter ideas, this hexagonal tool positions your brush in precise alignment with the centerline of a holder for Magnehone's (and, I suspect, others') brush hone(s). It has two alignment possibilities: one for "conventional" brushes, and one for "vertical" brushes. A few rotations of the hone (of whatever size you use) and the brush is radiused. Comes the debate: is this the way you should radius your brush faces? Depends. There is a valid argument for radiusing the brush faces in the assembled endbell while it is properly attached to the can, and while using the intended springs for the pressure source. I have, at various times, and for various reasons, done so. My opinion? Geeze, what a pain.

I'm so careless, I have to preload the brush hone with a spring to prevent inadvertently withdrawing the hone from between the brushes (this action is immediately followed by an interesting "Click!" noise, as the two brushes snap into one another and obliterate their respective faces). Yes, I could do one brush at a time on its respective side (which means that if I messed up with the hone, the brush would have to go all the way over to the opposing brush hardware to get ruined). Yes, I have to reclean all the parts to get rid of the brush dust. And yes, if I flapped my arms fast enough, I could probably fly, too. Well, sorry, but I buy airline tickets and use the Turtle unless the person I'm building a motor for demands otherwise. Additionally, I've never seen any performance difference between the two methods, and might, in a pinch, bet real green, rectangular dollars that there probably isn't anyone in the country who can tell me how and in what orientation method a bush was faced after a break-in on a power supply and a few passes down the track. This is a threshold-of-pain-in-the-butt purchase; if/when yours is exceeded, buy a Turtle.

Tool, Bushing/Bearing Installation & Alignment - If it were up to me, this would be the second or third motor-specific tool I'd buy (while purchased in conjunction with the can sizing tool, below). Provided it was reasonably accurate. How so? I own a bunch of these things, made by several different manufacturers. I had to buy more than one to get something that fell within an accuracy range I was comfortable with (+/- .002", and I'd like it to be less). Some were as much as .012" off center in one or more dimensions (the centerline of the shaft was measured at both ends on a surface plate with a digital height mike, then flipped over and measured again on the opposite surface; the same was done to both sides of the tool). Remember the business with armature blanks? I suspect some of these were made the same way. One, supposedly for a C-can, was big enough to actually turn down to the proper side radius and dimensions, then chuck up on a surface grinder to redo the flat surfaces to a correct plane and dimensions. If there was enough excess material to do that, it was either a S16 tool mispackaged, or a really bad job on a C-can tool.

Lacking exotic tools and a surface plate, how do you measure one? Use the thin blade portion of a dial or digital caliper, one end on the shaft and one end on the body of the tool in the dimension you're checking. Understand that what you measure will be greatly influenced by your ability to position the caliper blades at exactly the same spot along their length, and at exactly the same corresponding location in the other direction. Given the imprecision of this method, what you're looking for is gross misalignment, not perfection. A good bushing tool, with a tolerable level of error, is still much better than no tool at all. Why all the harping on precision here? Given that this tool provides the theoretical ability to insure that a) the centerline of the armature is in the true centerline of the can, b) that the magnets are both equally-sized and disposed from that centerline, both before and after honing, c) that the endbell is positioned in a correct relationship with the can and that d) its bushing/bearing and hardware are similarly registered off that centerline, is there any question that an accurate tool is useful?

Tool, Can Sizing - These tools are invaluable for accurately (or grossly, for that matter) dimensioning the internal surfaces of C-cans by altering the external configuration (yes, they're also available for our old friends the 16D series, and no, I never found one that would work on more than one manufacturer's can dimensions - sometimes. Still looking, though). As discussed elsewhere in this section, cans (particularly C-cans) are stamped and formed products being asked to do fairly precise things. The very nature of the manufacturing process works against that being easily accomplished, so don't expect miracles. Once you get past whatever form the internal facet of the seam spot weld has taken (or after you've ground it flush), you may note that the primary distortion in the can tends to be either what you can't fix (the misalignment of the the can sides or endbell mounting tabs) or what you should fix (the distortion of the can bushing-mount surface). Since I knock the original bushings out of cans before I do anything else, I use this tool to reform that surface as close as possible to a 90º relationship with the top, bottom, and sides of the can. A machinist's square (above) will help a great deal here. The rest of the dimensioning is up to you and the exact size of the tool you end up with (like the cans, they vary from manufacturer to manufacturer - big surprise, huh?). Contrary to some methods of motor building, I've never bothered to beat the living daylights out of a can in an effort to make it oversized in some way; if built to pass SDRA tech, it takes a lot of time, looks like ****, has a measurable, detrimental effect on the internal gauss readings of the magnets if not done precisely and uniformly, and, given the maximum magnet thickness, minimum arm diameter, and desirable air gap in C-cans, offers no significant advantage over a conventionally-sized can built to the same Rules. Let your conscience be your guide.

Tool, Demagnetizing - Sooner or later, the ability of the motors you work on to magnetize tools will a) amaze and mystify you, followed shortly by b) make you absolutely nuts. When used properly and frequently, a demagnetizing tool will help. They're available from a number of sources, and don't cost much when compared to a lessened frustration level. Follow the instructions on the packaging and experiment a little.

Tool, Timing, Armature - This is your admission ticket to the Great Timing Debate, in all its versions. Beyond simply determining whether an arm is high or low-timed (something, after some experience, you should be able to tell simply by looking at the relationship between the commutator and the arm stacks), a timing tool lets you ponder the mysteries of arm manufacturing. Most people who make armatures will tell you that the system and equipment they use makes it virtually impossible for them to mess up the timing of an arm, within a reasonably small margin of error. A good timing tool occasionally tells you that "reasonably small" may mean different things to different people. Consider: to be precisely spaced, no matter what their relationship or timing to the stacks of the arm, the slots in the commutator must be disposed 120º from one another to be considered accurate. Seem reasonable? Measure, say, 10 arms with a decent timing tool, and see what you come up with.

I have a timing tool that was made in a moment of whimsy by the proverbial aerospace engineer, with cost (apparently) no object and accuracy paramount. It indicates timing from the center of the slot along its surface, and is accurate to 1/2º (it isn't a small tool, either). I occasionally use it to check the readings taken with an MEC tool, which is smaller, cheaper, and easier to use. It does however, unlike its big brother, take readings via a blade inserted in the end of the com slot, a method some manufacturers will tell you is horribly inaccurate. Being the ignorant dunce I am, I sometimes wonder how the end of a slot that is supposedly cut at precisely the centerline of the arm shaft and continuously perpendicular to it can be that much more inaccurate than the slot itself. But hey, they make 'em and I just buy 'em, so what do I know? The bottom line for me turns out to be predictability. Given Xº nominal timing and Yº timing "scatter" (highest to lowest reading), the arm will probably perform in "Z" ballpark, taking arm meter readings into account. I don't buy arms by the gross, and work with what I get, and I've yet to find a "perfect" arm. No matter. Despite what some people would like you to believe, building slot car drag racing motors ain't rocket science, and sometimes knowing that something is "in the ballpark" is good enough. At least it is for me.

Tools, Cutting & Grinding, Assorted - After you get your first, second, or third motor tool, and spend some time standing in front of the Dremel display case wondering what on earth all those things could conceivably be used for, you're going to be working on a motor (or other) project some day and think, "If only I had a little dealie that could..." Go back and look at the Dremel case. That little dealie is probably in there somewhere. Some words of caution, however. There is a significant difference between tools that grind and tools that cut metal. A grinding stone, disk, or wheel actually sacrifices part of its surface when applied to metals (generally, the harder the metal, the more it loses or wears), and the output from grinding work is usually a uniformly-sized powder or grit comprised of various percentages of whatever metal you're grinding and the carbide/binder/whatever material of the grinding tool (and, uh, yes, if you do it right, you can actually start a fire with the sparks and incandescent material flung off from what you're grinding on). Messy, irritating, a pain to clean up, but generally not much of a problem when you use proper eye protection.

Cutting tools, however, work on the premise that a harder, sharper edge will cut a softer one (real rocket science, huh?). Most normal steel cutting work (and a great deal of stainless, as well) requires a carbide tool, while softer materials, e.g., plastic, nylon, phenolic, can be cut with a generic "tool steel." In all cases, the cutting "debris" output is an unbelievable number of tiny slivers of material. Having somewhat more mass than grinding debris, they travel further. Like everywhere. Pick the right steel and the right tool, and you can spend hours picking bits of steel out of your skin. This may sound like safety overkill, but as a person who already has a few rust rings on the surface of his eyes despite safety glasses, trust me when I tell you that owning and wearing one of the many full-coverage, flip-up face shields while cutting or grinding, even with motor tools, is not a bad idea at all.

Quite a long time ago, and based on our methods and actions in our race car shop, a mutual friend used to refer to me and my partner as "Captain Caution and His Trusty Sidekick, Sergeant Safety." Guess he was right, huh?

Torch, "Mini," Butane - When rapidly applying lots of heat to a subject is called for, as in those circumstances where two relatively large or thick flat pieces have to be soldered together, a small butane torch is most useful. "Small," by the way, means less output than the conventional propane variety you may already own. Butane is the gas commonly used in that type of cigarette lighter, and a vast majority of the mini-torches available are designed to be refilled by the small gas canisters sold for the lighters. Unless you feel like lighting it with some other flame, mini-torches using a piezo-electric igniter are best.

Volt/Ohmmeter, Digital - Sometimes you want to know if your power supply is lying to you, and sometimes you want to know precisely what the available track voltage is. Start with a decent but inexpensive one (available at our old pals Sears and Radio Shack). $14 - $20 should get you something useful that you won't feel suicidal about accidentally stepping on. Beyond that level, things get more expensive, more complicated, but not necessarily more utilitarian, until they reach the $300 - $400 level. Although I haven't spent a career looking, I've yet to see one at a price I can tolerate that would measure DC Amps at the level we deal with them, particularly surges during the launch of a car. When I do, I know it's going to cost approximately its weight in gold or some such. Until that point, the inexpensive Radio Shack units fit my needs pretty well.

Wheel, Wire, Small-Diameter High Speed - Great for basic cleaning, some deburring on softer materials, and primary polishing on endbell hardware. Also excellent for shearing infinitesimally small wires from the wheel and embedding them in your skin. Another eye-protection-is-a-must tool. I've tried all the cup and brush-shaped tools known to man, and have them all in my handy motor tool holder. I use the wheel almost exclusively. Pay attention to the size and condition of the wheel; as they wear, they have a tendency to rust after some period of inattention. They'll still work, after a fashion, but shed wires at an even greater rate. The Dremel wheels go for about $3, so replace them when they start to make you nervous.

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