Compared to a tjet,you have a lot more variables introduced into the equation with these cars.I'm talking of the barrel type brushes found on the Wizzard and Slottech cars.

I just rebuilt a Wizzard Storm that became a dog after some serious abuse.I polished out the brush barrels with Brasso polish and a couple of pipe cleaners.Installed some new brushes and silver springs,and hit it all with a dot of dielectric grease before assembly,and this thing goes like hell again.

What's some other tips I might need to know about with this type of setup.One thing I am uncertain of is how far to turn in the set screw.Do you just turn it until you get the max rpms????
I'm running the screw in all the way,then backing them off a notch.

Mike

I'm running the screw in all the way,then backing them off a notch.
You don't want to do that with new brushes and springs because it basically kinks and crushes the springs against the brush tubes and renders them ineffective.

Brushes on magnet cars give the same indications as brushes on a pancake car. Too little tension and the comm turns black and the arm runs hot. Too much tension and you end up with a shiny groove in the comm and the arm runs hot. If your comm is starting to take on an hourglass shape and it's not very old then you've been running with too much brush tension.

The best way to setup brushes is with a dyno or a voltage source/ammeter combination that you've used enough to know what constitutes a good setup. Without such a setup the next best thing is to use trial and error and when you get a good starting setting that works measure the width from screw to screw using a dial caliper or micrometer. The next best thing is to use trial and error and a non contact thermometer to see if you are getting continuous heat buildup over time. After that it's trial and error and your temperature calibrated thumb.

I prefer to start out with lighter tension, just enough to keep the comm from turning black, and add then add more tension only if the car loses power over time. A little adjustment goes a long way. If you look at the set screws on an out of the box Storm they are a lot further out than what you are probably running. What often happens is that with the proper brush tension the set screws tend to vibrate loose and fall out so people crank them down to keep them from falling out. What you really need to do is set the tension correctly and use a tiny bit of removable thread lock compound to keep them from backing out.

Everyone sets up their cars differently and I prefer to be more conservative to avoid cooking expensive parts. Running with lots of brush tension can and does get you more speed for a short sprint race, but you may smoke a $10 arm if you push it too far. Not to mention chewing up brushes like there's no tomorrow.

Hey Mike, two replies here in one day!

Talk to Harvey about brush setup as well, better yet get ahold of Jim S (schnoid) and hook up with him at Zeps, I think he lives nearby and I believe he has a dyno. We had one available at the race, it makes for quick setup.

www.rabbitracing.com ,,, purple loctite for your brush barrel screws :D

Gene: I'll do that.I plan on putting a word out on the other board to see if anyone wants to meet my son and I a week from this Saturday just to bs and turn some laps.I have a few new cars coming,a G3 poly mod and a hooked up Scorpion.
I'm getting too comfy on my setup,I want to try some others.

I like the idea of a dyno.Having been a musician most of my life,I can set them up pretty good listening to the pitch of the motor.I go for the highest pitch I can get without cranking them in to the max.

Goodwrench: That was something that was on my list.Especially since one backed out on me last night while I was doing laps.

Mike