2, When is the time to consider using aluminum pans? Are these pans exclusively for very high down force bodies?

3, What is trying to be accomplished by the play / slop used in flexi pans? How do you determine what is too much or too little? Some chassis seem to have major differences in the amount of pan play at the front of the chassis compared to the rear and vice versa.

I always enjoy your articles in SlotSide and your postings on the bulletin boards. Thank you for making yourself available in this format.

Tom.......

Hi Tom!
Always happy to help. I personally find my cars a bit more stable with the pintubes floating, but some other great flexi pilots in my area, most notably Duran Trujillo, don't bother. I recently re-evaluated this when one of my team guys went on a hot streak, and didn't use tubes at all (clips- ugh!). He was outrunning me, but when I tried the clips I went slower. So, do what feels good to you. I AM pretty sure that most of the motion should be in the rear tube. I open the hole to about .070, and use the stainless tube for a total of .020 play. Side to side needs to be enough to be free in the chassis, but with the body stretched over the car, I doubt it moves much sideways.

Aluminum pans, to me, are usually not worth the trouble. If the track is VERY slippery, or VERY swoopy, there might be an advantage - and thats with a GTP body. I've never seen one SUCCESSFULLY used in a Nascar or Nastruck situation, even on the banked ovals. I once had an offer to use a car with Aluminum pans on a dusty hillclimb where most of us were way slow compared to what the track was worth on a better (stickier) day. I was .015 faster with the light pan, but raced old reliable. I still TQd and won, and the other guy used his car for 4th. I guess I would have won by more with the faster car- maybe - but then again, perhaps my consistancy was the only reason I won. Makes you wonder...

Motion in the pans allows forces which are trying to deslot you to be isolated from each other. Usually, a lot of 'rock' improves traction, but isn't as easy to drive. Sideplay works opposite, lots of play loosens the car - usually. Some cars just don't obey the theory. Like most everything else (gear ratio, tires, ride height, spring tension, etc.) there IS a best setting for given situations, but you have to fiddle to find it. I generally prefer the car to slide more than tilt, but know drivers who feel differently.

The number one tip, as always, is to do your homework. The more setups you try, the more likely you will be to feel confident that you've found a good one.

Good luck, and good tuning,
Techman

Thanks,
Randy

Randy,
There is very little that works on a super 16 that won't also work on the stock.
The number one limiter is still the rules. If you can use the AT setup, do so. If you can use the new Hershman/ProSlot arms, do so. The Mura/Parma arms are a next best choice, certainly better than the Chinese ones. On the domestic arms, use the high timed ones, and gear to reflect the increased RPM.
If you must use Chinese arms, but you can use the AT setup, DON'T advance the timing on the arm, just do it in the setup. This will be the most reliable. If you must use Chinese arms in a Parma setup, try to find the speed coming off and going into corners, by worrying more about punch and brakes than bank speed.
If you find yourself with more specific questions, feel free to write again. I hope you enjoy the rest of Slotside, too!

Techman

Thanks for any help you can provide.
Mike

Mike,
Good to hear from you again. In the following paragraphs are a lot of stuff, but don't feel bad if you never acquire it all. Much will depend on the classes you race, and after the essentials, you can often borrow or hire out a service to do or get done what you need.

Essential: Allen wrench, .050, preferably the ground drill blank type. Don't skimp here-get a good one that fits both the screws and your hand. Soldering Iron, 40 to 50 watt. The Ungar, now sold by Cooper/Weller, is the old favorite, but I use a Haako #455. Seems to last better and recover heat quicker. Small straight blade and phillips head screwdrivers. Exacto type knife. Small hand held rotary tool-Dremel is the old standard, but I use a permanent magnet Ryobi, which has more torque, a longer cord, and more variable speed settings. A variety of accessories for the grinder, most especially thin stone cutoff wheels and the mandrel to hold them (Dremel #409 is a standard). Selection of small pliers. Sharp good quality scissors (I use straight bladed ones only, but some people actually prefer curved for certain cuts). Clear liquid acid soldering flux, and also a tin of paste flux. A heatproof, flat block to solder on. Its helpful if its size is such that you can set the car on it flat with the wheels hanging over the edge. Several manufacturers make them cut out this way. Wire brush. Alignment bar. 60/40 or 63/37 solder. Ruler/straightedge, metal.
A step up, but still essential for the serious builder/racer: Power supply, variable in voltage, with ammeter, and sufficient to run your hottest motor. Magnet gapping slugs in the sizes used for your racing classes. Magnehone hood hone. ProSlot guide threader. Magnehone 'Turtle' brush grinding fixture, with several sizes of rotor. If in an applicable class, magnet hones in useful sizes. Small, but decent, VOM or multimeter . Another step up, but still used by many: Comm lathe, tire grinder, small drill press, vise, airbrush, small compressor, toaster oven, magnet matcher (as opposed to guassmeter).
Total fanatic (I'm guilty of some of these!): Magnet zapper, balancer, portable electronic thermometer, scale reading in .1 gram increments, true gaussmeter, micro-ohmmeter, inductance meter, other professional machine shop capabilities (lathe, mill, surface grinder, etc). Motorhome to go to races in. Independant wealth...

Good luck, and good collecting.
Techman

PLEASE GIVE SOME INFO ON GAUSE READINGS.
WHY DO MY READINGS VARY SO MUCH.

IF A SET OF MAGNETS ARE MATCHED BEFORE ZAPPING WHY DO THEY BECOME UNMATCHED AFTER THE ZAP????

ANY INFO WOULD BE GREATLY APPRECIATED.

THANK YOU
DENI

Deni,
You didn't mention what type of gaussmeter you have, but the highly variable reading usually have something to do with how the measurement is taken.
Most of us think of a magnet as a single unit, when it is actually a collection of millions of small particles which are known as magnetic domains. The strength of the magnet is related to how well aligned these particles are with each other, and how consistent their polarity is. Materials which magnetize strongly are both uniformly aligned and have a great majority of the polarities in the same direction.
Permanent magnets lose strength when some of the domains reverse polarity (which makes them more stable). A good zap turns them back in a uniform direction.
It is entirely possible, even likely, that a ceramic magnet will have stronger and weaker areas within it. It is made, as the term 'ceramic' indicates, from a clay-like slurry of materials that harden when dried and heated. The presence and strength of a magnetic field around the magnet as it is cast and baked sets some of the domains in a fixed orientation. The mixture can certainly vary, although modern manufacturing tecniques minimize gross differences.
Now, when you use your meter, unless the probe is somehow shaped and sized just like the surface of your magnet, you will measure not the total field of the magnet, but parts of it at a time. I've seen differences of over .2k-gauss on the inner face of a single super16d magnet - and the motor ran well.
You need to develop a test procedure that delivers meaningful measurements to you. I gave up on hand held 'wand' probes, and now use a TrikTrax matcher. It at least holds the magnet at a consistant distance and angle from its sensor, even if the numbers aren't calibrated in gauss units. You could probably build a fixture of some kind to use your meter in this way.
As for the pair that became less matched after zapping: They were fundamentally different to begin with! Their initial match was an accident. All matching should be done AFTER zapping, when you have done all you can do to maximize the magnets. This is not to say that stronger is better (its easy to overmatch a mild wind like the 16d), but truly matched, even if weaker, should be better.
Good luck, and good matching.
Techman

Thanks,
Jim D.

James,
HO racing is not my field of expertise, however your questions have answers that can be useful to beginning racers in any scale, so I'll try to answer them.
Making a stock car go faster does, as you suspect, have a lot to do with both gear ratio and armature. In HO, there are a number of sources for 'hop up' armatures, among them Scale Auto (BSRT), Wizzard, Slottech, and Legends. Their addresses or phone #s are available in Scale Auto Racing News magazine, offf the various HO BBs, or at their individual websites. There are many links right here at Slotside, so start surfing!
No slot car in any scale will work well, if at all, with 1:1 gears. These small motors turn much faster than you would ever need the axle to go, and must be geared down to have enough torque to turn the axle against the forces of friction, inertia, drag, gravity, and in the case of HO, magnetic attraction to the track. Usually, when you get a faster armature, you will need even lower gears than come stock, because the effect of the hotter windings is to increase RPM, but not usually torque. This is true in all scales. Exactly what ratio to use can only be determined through experimentation, as there are a LOT of variables. The most important will be: Type of motor, length of track, power supply, weight of car, tire size, and what will fit on the car! You need to make small changes, and evaluate each time to see if there is an improvement. If there is, keep going that direction until there is not. Caution: What runs fastest will rarely also run for as long!
To calculate the speed of any slot car, you need to know how long the track is, and how long it takes to make a lap. First, figure out how fast the car is in some units of speed and time, then use conversion factors to get to miles per hour or whatever unit you really want. As an example only, lets say your track is 20 feet long, and takes 3 seconds to make a lap. You are therefore doing 20 laps per minute, or 1200 laps per hour. This is 24,000 feet per hour, or (dividing by 5,280 feet per mile) 4.545 miles per hour. Yes, thats pretty slow. Now, take the case of a really fast 1/24 car that can do a 155' lap in 2 seconds: it works out to 279,000 feet per hour, or 52.84 MPH. Thats real MPH, not scale, and its the average speed, not just the straightaway speed! Such a car actually can go approx. 70 MPH. There have been a few 1/24 slot car dragsters that have been clocked at over 120 real miles per hour, quite a feat when you consider thats from a standing start in just 55 feet of straightaway!

Good luck and good HO racing.
Techman

Joe,
Your setup isn't too far off what I would use, and I'll detail the differences after answering the first question.
ALWAYS run the smallest tires and least clearance that your rules allow - period. Then, adjust the gear ratio based on the tire size.
Most rules (but of course, I don't know YOUR rules) call for .750 minimum dia. tires and .063 clearance. On the Champion Turboflex chassis - and I agree with you that this chassis is the best for your purposes- you can, if you are careful, use .760 dia. tires. I often use Alpha Piranha or ProTrack Euro. The protrack is a great hub, but its a lot easier to strip the setscrew, and you need a lot of washers. There are a few custom makers of tires that have great stuff too, most notably Lee Gilbert and Dennis Kershner. They are expensive, though. Check the chassis carefully, using a calipers and measuring across the axle and the bottom of the center section. One side should match the other. If it doesn't, play with a file to gently enlarge the taller oilite hole until the height does match, then solder it up to make it permanent. I don't use any braces on a Turboflex, but if the local races are messy, consider a "U" brace twixt the uprights. I also use plastic spur gears to keep the rear end light. Ditto shortening the axle. Every little bit counts.
On your track, I would be running 10/39 with the .760 tires. The clearance on a 39 may not be sufficient, but we sorta ignore that here if the gear is plastic. If your tech dude objects, run the 38. Now, I use the 10 pinion because I use ProSlot arms, and they have more torque than the RJR. I agree with the 9 for the RJR. In my experience, the P/S is just plain faster in the long range. I also use ProSlot brushes (or the Mura, I can't tell any difference in the way they run). I haven't tried RJR brushes since '94-and they didn't work as well then, but I know Robert claims they're better now. He also claims the storm chassis is good too, so consider the source. You couldn't pay me to embarass myself on the track with a storm...
The only other difference I read was the springs. I use the Trinity light (which are a bit stronger) or the Koford m313, which are about the same as your Champions. I just don't like painted springs. BUT, thats with the ProSlot arm. For your RJRs, give a try to Trinity mediums or something else a bit tighter. The punch and brakes seem to improove.
A final note, concerning the lead weight: The only condition I can cure with lead is tilt, and in that case I try different tires first. If you are lifting the nose, try moving the body forward, or using a bit more front tire clearance. I hate to add weight to a car that already is over 125 grams! Of course, you'll do what you have to - just don't look to weight as a cure all.

Good luck, and good tuning!
Techman

(2)I drag race slot cars,and i do it with s-16 motors and need to know more about the motors i race with no one i know knows about s-16 motors and like to get them to a little more power....

Thank you
Rick .S

Rick,
Super16d motors other than the AT have between .025 and .030 air gaps, each side. This is the physical clearance including the green coating, but inside it is the same blank as the stock 16d, so the effective gap is more like .034.
The AT (adjustable timing) setup from trinity is a little bigger inside, for an effective airgap of .039. It also has larger openings and no sheet metal shims. This frees up the rather heavily wired armature for more revs, and advancing the timing will produce even more. This is good news for the road racer, BUT, for the dragstrip, with its higher voltages and premium on acceleration, you may want to actually use less timing, and shim the magnets. I have not yet been able to devote the time to determine some good numbers, but its on my agenda.
Many of my customers go ahead and use my road race motor, and gear to reflect the higher revs. You can read about this setup in the Techman article elsewhere on Slotside, "Building the killer S-16D".
Check your rules carefully! At least one of the popular drag sanctioning bodies in my region will NOT allow the ProSlot armature, whereas the local USRA is fine with it in roadracing. If legal, its certainly faster and more consistant than the Chinese arm. At the same time, this sanctioning body allows the 'outlaw' shortstack super16d arm, but the USRA does NOT. Go figure! The shorter arm is DEFINITELY faster! Naturally, there is a P/S version of the outlaw, and its the fastest of all.
I'm going to guess that a total magnet space of about .550 (airgap .018), about 35 degrees of timing (any way you get it, arm and endbell combined), heavier springs, and around 3.6 gearing (13/46) with 1" tires will be a good start, but like anything else, theres no substitute for YOU doing your HOMEWORK!

Good luck,
Techman