Marcelo,
The smart brake sounds very much like the Cidex in function. You might want to try it, but I prefer the variable resistor approach to brake adjustment. Remember, NO DEVICE can make the car brake harder than a plain 3 clip controller system unless it actually injects a reverse voltage (Illegal under most rules). It can only adjust the braking effect to be a lesser amount.
The Slick 7 and Arlington power supplies are just that: Supplies. They offer variable voltage and meter the current draw, no more. The Slick 7 is very simple, easy to fix, but a bit bulky. The Arlington features digital meter readings, and is quite compact, but not as robust in ability to deliver big power.
You are not mistaken about the effect of the DMW comm drops, or any other. They work by softening the brushes, allowing almost instant breakin, but cause extreme brush wear and leave a conductive paste of brush particles in your comm slots, which soon slows the motor. I DON'T USE THEM FOR ANYTHING EXCEPT HEADS UP DRAG RACING.
Good luck in your racing! Techman

Dan,
Yes, back in the sixties this and similar schemes were tried, obviously with little or no success. I even had one with the short pivot arm sprung to allow controlled side to side motion, in an attempt to cushion the chassis from the sudden sideways force of entering the corner. No improvement, broke easily.
A trailing guide arrangement works OK (look at the basic function of the guide pin in an HO car), but since the body of the flag must now fit under an extended tongue, there is a loss of space to fit the lead wires under a lower body. Again, no real benefit so no real justification for the increased complexity.
Keep thinking, though! Every actual improvement, on a slot car (or any car, for that matter) came from someone's imagination. The next revolutionary idea might just as well be yours!
Techman

Brian,
For boxstock, the major changes are a reduction to 72 grams minimum, and a rule restricting brass weight plates to the front inch of the chassis, still solidly attached.
You can now mix otherwise legal magnets between brands of setup as well. For a discussion of rules changes, check the USRA website at Fastlane.
I hope you can make it out to the Nats. There is no better learning experience in all of slot racing.
Good luck, and good racing. Techman

Bob,
You have the Techman stumped! Actually, I build and race slot cars in a modern commercial setting, and have no contacts for vintage or collectable goods. I have seen where several dealers of collectable slot cars and parts have goods for sale at Ebay, the online auction site. They may or may not have the items you need, but are likely to at least know of potential sources.
If you don't require exact replacement parts, try contacting REH distributing in Cincinnatti, Ohio. They have both HO and 1/32 scale stuff. While they won't sell to you directly, they should be cooperative in steering you to a raceway or hobby shop willing to place the order.
Good luck in your search! Techman

Jay,
You are probably correct about the one piece of track having a poor connection. Its inconceivable that the rail itself would have higher resistance, so its at a joint.
Try removing one section at a time, cleaning the contact areas well with fine sandpaper or steel wool, and reassembling. Each time, for the straights, you can also turn the section 180 degrees. If this cures the problem, great. If it moves to the opposite lane, then at least you've identified which piece it is.
One other likely spot is in the terminal section. I have'nt looked at the underside of SCX sections in ages, but I seem to remember the actual connection from the controller plug to the rail is open for inspection.
Small shims made from tinfoil may be indicated to fill a loose rail joint. If your layout is more permanent, and you don't intend to disassemble it, you can actually solder the sections together, but be quick to avoid melting the surrounding roadbed.
Good luck, and let us know what you find - I don't want to lose sleep over it! Techman

Mark,
Since you've found Slotside, you have access to Techman's article on building a killer Super 16d motor. Just about all of the tips there apply to building a 16d as well. If your rules allow, make sure to use the D-Spec armature from ProSlot/Fast Ones.
On a 16d, which is not balanced, the biggest variable is the relative amount of imbalance present in a given armature. You may have to go through a few to find one that doesn't rattle too much. Compared to the Chinese 16d arms, the American made ones are much more reliable. This means you can gear for more speed without melting the comm connections. A fairly stiff spring is indicated.
A Challenger motor, also not balanced, is as close as a C can gets to the basic D can motor. I personally believe that the Champion arm, made by ProSlot, will be faster than the Mura in most cases. Ditto for the RJR Hornet. All these arms have a lot of wire on them. While they will spin faster than a 16d because the lamination stack is shorter, they still aren't high RPM motors. Therefore, a lighter, thinner, can and larger airgap should be beneficial. Try the ProSlot or Champion setup (they're identical) with Mura magnets. If you use a can tool as a mandrel to beat the can into shape, you should be able to raise the airgap to about .535". Use the same tools and procedure as you did on the 16d to align the hardware and size it for GoldDust or Bigfoot II brushes. The only difference is that you don't usually solder the endbell hardware to itself on C can hardware.
Good luck with the building, and get back to me if you run across a more specific question while deep in the project. Techman

Ryan,
You can't imagine how refreshing it is to hear from a slot racer who LIKES to build stuff! I personally think that racing was much better when people typically built more of their equipment.
What else to build? You could try: Chassis jig, body mounting patterns and jigs, mounting blocks, armature holding blocks, tire trees, controller hanging brackets for your local raceway, display quality blocks with clear covers, and of course you've barely touched chassis yet. Perhaps the greatest challenge is straightening and limiting C1 or GT-12 chassis. If you're REALLY ambitious, you could even try a magnetizer, and if your both ambitious and a bit masochistic, your own track!
I've done all the above, and learned a lot by doing so. There was no formal shop training involved.
Don't forget chokes, tire truers, or possibly even a dyno. And, while you may already have done so, body painting is usually rewarding. Good luck and good building!
Techman

James,
For the type of racing you do, the Turbo is quite sufficient. What you will eventually come across is a class of racing using more powerful motors, or a track with significantly faster and/or slower sections than you are used to. At that point, you will want a controller with a different response rate, as well as the ability to handle more power without overheating.
Silicone wire, bolt on heat sinks, and an extra resistor or two in different ohm ratings will do for inexpensive upgrades. Variable brake rheostats, external resistors, and 'clicker' boxes (full power relay shunts) are some more advanced modifications.
If you get real serious about the racing, consider a high end variable response controller like the Ruddock DR 40. Sure, its expensive, but it allows you to handle any car on any track. As an alternative to constant upgrades, it could end up being a bargain!
The scalectric cars will run at the commercial tracks, but not well. A guide and braid designed for the big tracks will help. You will also be more comfortable with a controller resistance of 15 to 25 ohms.
Good luck and good racing!
Techman

Steve,
Believe it or not, the simple diagram on the back of Parma controller packages is all you need! Add your relays as a switch into the white wire, and repeat the circuit for each lane. The SRT manual also gives details of how to route the relay control wires as well as (optional) wind up timer switches.
The power taps every 30 or so feet are just extra extensions to the black wire hookups. From the black wire controller post, branch as many as you need to the points around the track. All this results in a lot of wire down there, but the circuits remain very simple.
The total power you need depends on the cars you will race. ERI distributing, local to your region, carries excellent power supplies by Rivergate or Power Source. One will do for 16d type motors. Two in parrallel will handle Super16, American group 10's etc. For X-12 and up, or any class run with glue, batteries using the power supplies as a charger are reccommended.
Braid carries more current than foil tape. Also, it's textured surface makes better contact with the cars as things get dirty.
Sorry, I know of no books for rental equipment repair. Most controller failures are due to hooking up wrong, or allowing the controllers to be used with faster cars. You can wire the controllers to three conductor plugs and put matching sockets on the driver panels to make the hookup foolproof.
Finally, the diodes that parallel the relay coils are there to block an inductive voltage spike, generated by the relay being turned off, from reaching the computer. Always follow SRT instructions TO THE LETTER! This would include the diodes, fuses, and separate cable instructions. Mike at SRT is excellent at providing tech support over the phone!
Good luck, and have fun with the project. Techman

David,
One big missing piece of info: What class of racing is this? The gearing sounds funny to me, but there are a few C can classes where you might gear that high. You are also using 48 pitch gears, and that sounds funny too for a class that allows a springsteel chassis.
Will this faster racer give you any advice? Many, if not most, good racers will share info. If the motor is an X-12 or a Superwasp, you definitely need a smaller pinion. If it is a Challenger II, you may still get some good results with a lower ratio.
Is the motor reasonably fresh? Are the springs OK? Are you running the smallest tires that will pass tech? Is the car smooth and quiet? All are possible sources of speed.
300 laps in a race is 37.5 per heat, an average of 4.8 seconds per lap. The last race I ran with similar numbers on the same type of track was a Super16d 4" Nascar. The notable difference is that the TQ was 4.38 seconds. I always sense something unusual when the qualifying and practice laps are so far ahead of the race laps. Are the races relatively clean? If not, maybe you don't need speed until you get more consistant.
Shoot me some more info - maybe then I can figure something out.
Techman

John,
Techman hates to play favorites when there are only two alternatives, but... the ProSlot arm seems to have the distinct advantage right now.
There are two major differences. First, the P/S blank is still a bit lighter and narrower in the web, allowing lower resistance and higher RPM. In their favor, Mura did redesign the blank last Spring, and its much closer than before. For drag racing, it may even be better.
Second, and this is the big one, the ProSlot commutator is considerably better. First, its thicker plates allow more retrues. Though not important in 16d, it also is more reliable at high speeds of say, group 20 or cobalt 12. The ProSlot comm is also a smaller diameter than the Mura. It gets pretty technical, but the effect is that there is more brush contact on the P/S relative to its rotational speed, which has the same effect as more timing. Ironicly, this difference is magnified by the Mura being sold in Parma setups (no timing adjustments), while the P/S can be had in the Trinity AT (adjustable timing) setup.
Critical note: BOTH armatures are often SLOWER than the chinese arms UNLESS you run lots of timing! This is because the chinese comm is the smallest diameter of all. High timing that would cause early death of a chinese arm won't hurt the Mura or ProSlot arms, since they have welded connections and better epoxy.
The final proof is on the track, where, from race reports around the country, the P/S arms are winning anywhere they are both competing head to head. This is not always the case, as the Mura is allowed a few places that the P/S is not, either because of its being available sooner (New England) or for certain manufacturer ties (such as a few locations in Northern California).
As always, Techman advises you to do your own homework, and test various setup combinations on both. Good luck. Techman

Greg,
OK, thats a bit different...its still a slot car though, and should respond to the usual tuning techniques.
Is your chassis as low as you can make it and still pass tech? Womps are supplied with oversize tires, and getting the center low is the first thing to do.
Next, widen the front track width without adding spacers, anotherwords, let the front wheels slide from side to side. If you've lowered the car properly, the fronts should nearly touch the track as well. Remove guide spacers if necessary.
Womps run good when heavy. Try lead all the way back on the sides, not just under the axle.
They also tend to tilt. Try running a narrower tire, or a firmer one, or both. Any car will handle better when it slides smoothly.
Don't neglect making it run smooth. The newer Parma crown gears (the pink ones) are a big improovement. Try also setting the mesh a bit tight, and using a heat gun on the gear while spinning at just a few volts on the supply. You will actually hear the gear smooth out as it acquires a better toothform. Stop immediately when the sound changes to avoid melting a tooth or two off entirely.
Womps are a great car to learn basic tuning on - and driving too, especially if you've overpowered them on purpose! Good luck, and have fun.
Techman

Ralph,
I don't beleive that you can get a significant gain in timing by zapping the magnets with the can rotated in the zapper pole caps. The magnets used in your motors, while not that great, are a good enough material that the field shape is fairly well set. Zapping them a few degrees off center won't change them, and going a long way off center is more likely to weaken them than anything else.
This concept was fairly popular in radio control racing some years back. At the time, the magnets weren't as good as the ones used today, and the '05' size motor had magnets that went much furthur around the armature than they do in a slot car motor. You don't hear about it anymore...
Any slot car motor, including the sealed ones, can be zapped. If it has cobalt magnets, it will take a much larger and more powerful zapper than the ones found in raceways. The effect? There will only be an effect if the magnets are below their peak strength when you zap them, in which case it will be restored. You CANNOT zap a slot car magnet to a state where it would be any stronger than it was when fresh, no matter how powerful the zapper is.
Good luck, and good racing. Techman

It sounds to me like it is similar power to Alpha's track but with a few more amps. Group 27 is being run with the addition of a power supply.

Wondering what motors would suite. I am a Koford racer and am thinking of trying their new .480 7/24.5 or 84.5 arms in a quad set up or even single magnet set up on this power.

84.5's .459 with either quad or single mags is my other choice.

Whats with 6 magnet set ups? Are they a gimmick or more suited to very high power situations.

Any advice would be appreciated.

Have a great Xmas & New Year

Regards,
DENNIS

Dennis,
I haven't raced group 7 for a few years now, but I keep my ears open! My weapon of chioce has always been a .480 diameter arm, first Camen, then later on PK, and most recently ProSlot.
When Koford first made a .480, it was on the 27 blank and didn't work so well. The new ones are an all new blank, and they seem to really fly. Both the big races this year (Worlds and US Nats) were on modest power, and both were won by .480 arms. Ditto for the six piece magnets. They may be even better on high power, but seemed to do just fine on modest power. No gimmick, solid theory behind them, though they're just a bit easier to break.
If you're really going to run on batteries with no voltage boost, don't be timid - try the 64's! At Alpha, two 64's on .480 arms, straight up, is a reality!
Good luck!
Techman
P.S. - I've had literally hundreds of questions posed to me on this forum, but yours is the first from a group 7 racer. Thank you - its a bit refreshing!

Jerry,
In some classes of slot cars the body improves handeling, and in some it doesn't.
You need to compare the handeling of your car to the other guys racing in the same class, so you can tell if its your setup, or something basic to the class. If other racers can get a similar body to handle better, then its time to go to work!
Larger cars like the older NASCARS of 30 years ago put a lot of weight up high. Trim it as low as your rules allow. If its a hardshell, try to grind some weight off the inside. If its a lexan body, keep the paint light.
Pay attention to how the car deslots. If it slides, try wider, softer, tires. If it tilts, try harder, narrower tires. If it lifts in the front, add a bit of weight behind the guide.
Always try to get the local hotshot to help you. Most racers will be flattered that you asked. Often, some pretty simple stuff like the amount of guide washers, how the guide is mounted, how straight your axle is, or how loose your bushings are will make the difference, and an experienced racer can figure it out in a glance.
Finally, although I was writing about a NASTRUCK, check out my article on 'Building the Killer 4.5" Truck' also on Slotside for many setup tips.
Good luck, and good racing.
Techman

I have a Cobra Com Truer and a Koford power supply. Recently I've noticed that the power supply is only supplying 4 volts when it originally supplied 5 volts. The power supply was purchased last March. Is something wrong with the power supply? Could something be wrong with the Com Truer?

Also, the Com Truer is leaving spiraling rings around the com. I'm still using a carbide tip cutter (I've cut no more than 20-25 coms). Is this due to something I'm doing, the carbide tip (which looks good under magnification) or the Com Truer itself. Is something wrong with the way I have the Com Truer set?

Thanks in advance for your help,

Randy

Randy,
Your power supply is probably OK. The comm lathe draws more current than most slot car motors, and leads to a voltage drop.
I doubt that there's anything wrong with the lathe either, except for the carbide bit. 20 cuts is actually a lot for carbide. While a diamond bit will set you back almost $100, the difference both in quality of the cut and in useful life is amazing. I have over a thousand cuts on my diamond tip since it was last resharpened (your mileage may vary!). If you have the means, get the carbide lapped, and if that solves the problem, start saving for the diamond!
Good luck, and good truing! Techman