BobW

iTrader: (1)

Thought I would chirp in here since this ties in nicely with a new Chassis Dynamics module I am working on for RC Crew Chief. This feature is not in the current version but should be added soon. Check out the Youtube screencast video.

http://www.youtube.com/watch?v=EBn79...hannel&list=UL

yxiaocheng

iTrader: (18)

How much of the sidewalls should I glue? Do I need multi layers or one layer is fine?

Souk

iTrader: (22)

What I usually do is give the car a small amount of throttle and run the ca just up the side wall. You do not want to be going on the contact patch of the tire or else you will compromise actual traction. Just do one layer, sometimes it last longer then you think. And if you start traction rolling again just add some more.

EDWARD2003

iTrader: (8)

Gluing the sidewalls isn't going to solve your traction problem entirely. It's just a temporary fix to an issue with your setup.. You need to look more into your cars setup such as springs, oils, roll centers and so on.

DesertRat

iTrader: (2)

I respectfully disagree with Ed, gluing sidewalls is usually necessary on national-event level traction. The best, most consistent, and easiest way I have found to glue sidewalls was to put thin CA glue on a cotton q-tip, put the car up a stand and spin the spur gear by hand, and lightly coat the sidewall up to 2mm or so away from the contact surface. With the car sitting on the ground, the glued part shouldn't touch the racing surface. If you over-coat the sidewall and the car loses overall grip, adding a degree or two of camber can restore the cars grippy performance.

EDWARD2003

iTrader: (8)

Yes, I totally agree with your statement IF you're running on "national-event traction levels". The only time one should take this measure is if you've exhausted all other setup means. There are a multitude of setup adjustments to help with traction rolling. I personally don't know what traction levels yxiaocheng is running on, but I assume he's running on medium traction.



Also Martin Crisp mentions a few things about it as well.

http://www.rctech.net/forum/12938982-post31.html

DesertRat

iTrader: (2)

I agree, if he's on medium grip there are a lot of things to do first that will work. But I respectfully disagree with Martin's old post asserting that glue is only to be used "In rare and extreme cases." I think these rare cases are happening to racers a lot more often with the tires and sauce in use today. Partially because of these sort of advice, and the fact that Martin is a lot faster than me, for sure, I was very apprehensive about glue for years, and it cost me a few times.

As an anecdote, at the 2013 IIC I entered amateur (handout motor) touring and I was garbage. My car dragged the chassis and traction rolled like a pig, most of the internet advice I found made it even worse, but I never glued the sidewalls because somebody told me not to. Live and learn.

Fast forward to summer 2014. I broke out my old touring car for some club racing in California and on days when the grip got high enough the induce traction roll I was able to TEST every internet grip rolling solution I could find. I found the one that worked for me (almost no droop, light body, hard swaybars)... almost. I didn't glue the sidewalls because I thought that was only for rare and extreme cases. On the race day with the most racers, the highest grip, and cars tumbling end over end grip rolling nearly cost me an A-main qualifier when I was running what might have been the fastest single laps of qualifying, and grip rolling in the main did cost me and others many finishing spots. I was lucky the car wasn't seriously hurt that day.

At the 2014 IIC I had not intended to run amateur again. I was going to concentrate on pan car and I was still a bit sore and embarassed about my car doing barrel rolls the last year. BUT, my car was just running so well at club racing I figured it could at least take up some of the down time in the 6 hour break between my class heats. From the first day of qualifying and not having adjusted a thing it was feeling really fast, and lap times told me the feeling was showing on the track. It was running hard, but as racers were on the track 12 hours a day the grip kept climbing and in spite of the usual fixes I started traction rolling, costing me confidence in the car and many qualifying spots. I had actually only glued sidewalls once before, so I apprehensively made my sidewalls a little shiny with CA as described above, ran a morning practice and found some of the grip had gone, added a degree or so of camber all around, ran again, found the car felt just like it did without glue, and then I TRIED to traction-roll the car through the sweeper. I had to know if there was some still way I could completely wreck myself. So, full speed into the sweeper, twitch the wheel to full lock, full throttle at the apex, the inside wheels lifted a half-inch off the ground.... then set back down. Exhale. Now I could race into every corner instead of worry.

I guess I would say that if your car is well-adjusted and still grip rolls, don't fear the glue.

howardcano

iTrader: (37)

Agreed.

Grip levels usually aren't the same from corner to corner, so if a car traction rolls, it tends to do so only in a few select corners. If chassis adjustments are made to reduce lateral acceleration, and thereby prevent traction rolling, these adjustments will reduce speed in every corner, even in those where the car wasn't traction rolling. That's not good, and lap times will suffer.

Gluing the front sidewalls prevents traction roll, but doesn't reduce cornering speed in the corners where the car didn't have problems. That's good.

As you witnessed, glued sidewalls let the car begin to tip, but as soon as the glue contacts the track, the tires slip and the car plops back down on four wheels. If it tips a bunch, then go a little further outward on the tire with the glue. If you go too far, use a razor blade as a scraper (with the blade leaned toward the direction of motion, so it won't cut into the tire) to remove some glue (on rubber TC tires, not foam).