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Fun experimenting with slot cars


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#1 MSwiss

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Posted 01 March 2018 - 02:05 PM

At last weeks Wednesday night races, top racer, Michael Iga, during Group F warm-up, his car was uncharacteristically, real noisy.

It sounded like a bent hub or axle.

His car, while not quite turning the times he usually does, was handling fine across all 8 lanes, and he took the 3 lap win.

When his car finished the heat by me, where I race direct and marshal, I would check it out to see if the rubber was peeling off, or one tooth was chipped.

Nothing.

Fast forward to last night.

He warmed up, and if anything, the car was noisier.

He said he had changed, pinion, spur, axle, and tires.

He then switched bodies with another racer.

Nothing helped.

I took a few laps on Blue, running low 3.3's, not awful times, but not what he runs.

I finally said, recalling some unbalanced Rotor motors from 10-11 years ago, it had to be the motor being severely out of balance.

The racers seemed skeptical, because we had not seen anything like this before, especially with this particular motor, the 4002FK, in the couple years, we have been racing this class.

I told Michael I was convinced that had to be it, and since the motor wasn't great, would he mind if I experimented a bit.

I had Dremel with cutting disc handy, from working on pinned guides, so I quickly first cut the bottom strap off of the can, to see if I could change the airflow.

No change in noise, or lap times, but it didn't make a mess, so I pulled the body and cut the top off.

Still no change what so ever.

I was really surprised the lap times didn't improve, even just a tad.

The race started and Michael ran mediocre on both Red and Green.

Green Lane was exceptionally substandard for him, so I decided after the heat was over, I would try to balance the armature.

With the Dremel, I ground more on the stack, that already had a balancing hole, thinking that maybe, they didn't go deep enough.

On Blue, his lap times improved, but still were on the slow side, and car was still noisy.

So during a track call, I grabbed his car, and ground on a different stack.

The car went noticeably slower, which I took as a good sign.

It went from high 3.3's, to low 3.5's.

So between heats, I ground on the opposite side of the motor, the stack that originally had a drill mark, and a new stack.

When the heat started on Purple, Michael seemed to pick up a tiny bit of his straightaway speed, but the car was still noisy.

So during the next track call, I went after those two same stacks, real aggressively.

When the power went back on for the rest of the heat, the noise went away totally.

The car ran dead quiet the rest of the heat and rest of the race.

From the race sheets, you can see the obvious improvement.

His lap totals, and times, on the slower Black set, were way better, than the early heats, on the faster, Red set.

You can see he was over a tenth faster, on White, the last heat, than he was on either side, Red or Green, the first two.

After the race, I hot lapped on Blue, a 3.15, a tenth and a half faster, than before the race.

Anyway, it was fun to solve the mystery, and save my "Patron Saint of Wing Cars", some time trying to "fix" the car.

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  • Gene/ZR1, JimF, garyvmachines and 1 other like this

Mike Swiss
 
Inventor of the Low CG guide flag 4/20/18
IRRA® Components Committee Chairman
Five-time USRA National Champion (two G7, one G27, two G7 Senior)
Two-time G7 World Champion (1988, 1990), eight G7 main appearances
Eight-time G7 King track single lap world record holder

17B West Ogden Ave., Westmont, IL 60559, (708) 203-8003, mikeswiss86@hotmail.com (also my PayPal address)

Note: Send all USPS packages and mail to: 692 Citadel Drive, Westmont, Illinois 60559





#2 MattD

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Posted 01 March 2018 - 07:14 PM

Mike was it just trial and error on the arm grinding?


Matt Bishop

 


#3 MSwiss

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Posted 01 March 2018 - 07:21 PM

Yes.

My long winded post explains it.

Guessing totally wrong, the one time, ultimately, probably saved me time, in the long run.

The thing that really surprised me was the lack of metal dust where I didn't want it.

I hit the can with a lint roller every time I ground on it, but the tires never needed to be cleaned.

Mike Swiss
 
Inventor of the Low CG guide flag 4/20/18
IRRA® Components Committee Chairman
Five-time USRA National Champion (two G7, one G27, two G7 Senior)
Two-time G7 World Champion (1988, 1990), eight G7 main appearances
Eight-time G7 King track single lap world record holder

17B West Ogden Ave., Westmont, IL 60559, (708) 203-8003, mikeswiss86@hotmail.com (also my PayPal address)

Note: Send all USPS packages and mail to: 692 Citadel Drive, Westmont, Illinois 60559


#4 Pablo

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Posted 01 March 2018 - 07:32 PM

From now on, all my arms go to Swiss :D :crazy:

Mike, if you run out of Koford magnet putty, try a jar of Neon. I tested it, it works well, 99 cents at WalMart

 

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Paul Wolcott


#5 Bill from NH

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Posted 01 March 2018 - 09:16 PM

Available in red, yellow, blue, & green. It's also available in 3 lb tubs. Poster putty from the stationery dept. will also work.


Bill Fernald
 
I intend to live forever!  So far, so good.  :laugh2:  :laugh2: 

#6 Uncle Fred

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Posted 02 March 2018 - 08:25 PM

I balance my arms with a blow torch and a jack hammer.  Mike, if you do this on a regular basis your motor sales will increase.....


Fred Correnti





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