Hello all!
Yes, I am still alive but real life work has got in the way of all things RC for the last two months. So with the last round of the Eden Park Raceway Winter Series taking place today, I found myself desperately trying to incorporate the latest updates to my C2 at 2am on raceday...
Over the last two months I have acquired a Schumacher Cougar SV which I am going to rebuild and experiment with a few ideas. This will become my main race car, so the C2 is close to being pensioned off for now. However, the SV came with a LiPo battery (dead) and an Ansmann ESC. My plan therefore was to run the old LiPo which I originally acquired with the C2 and the Ansmann ESC. For reliability I bought a plug-in LiPo protector as the ESC doesn't feature one. So the plan was to run the same 14T brushed motor but with LiPo power and the Ansmann ESC.
First up I had to make a revised version of the top deck to allow for the longer length of the LiPo pack. I'd had to fit a power switch to the ESC as the previous owner had just twisted the wired together. With this in mind, I thought it wise to make sure the old ESC would still fit. Due to the rushed nature of the work, I'm not particularly happy with the quality. (Old on left, new on right):
One of the key requirements of the revised servo deck was the ability to change the battery pack without having to remove it. In doing this I have swapped the battery clamp for a standard 'Team' spec item which has been keyholed for simple removal. The LiPo protector is strapped to this.
Unfortunately the Ansmann ESC has wires sprouting from it all over the place. Coupled with the rushed installation, I wasn't happy with the look of the wiring but it would have to do:
And so it was with some trepidation that I arrived at EPR this morning. With the untidy wiring, I had an uneasy feeling that there may be some electrical issues, so I took the old ESC and Nimh packs for backup.
In practice I did several short runs to identify which tyres to use and to tweak the suspension settings. I'd rebuilt the shocks last night (30 oil in rear with 4 holes, 35 oil in front with 4 holes) and ended up setting the car up with the same rideheight as before but with more droop - this certainly improved ride over the bumps. Running with the LiPos I was impressed how much quicker the car was. Sure, it wasn't as fast as the brushless cars, but it was quick enough to make life difficult for people trying to get past. A definite step forward.
In the first round of heats, I was running really well (probably around 6/7th out of 10) before the car slowed before finally stopping with about a minute left to run. The symptoms were as if the battery had discharged, but upon checking back in the pits the battery was fine. And so commenced an infuriating day where I failed to finish every one of my four heats with the same problem happening sooner and sooner.
I systematically removed the LiPo protector and ran it - same problem.
Swapped the ESC for the old one - same problem.
Changed the transmitter batteries - same problem.
Swapped the receiver for my mates spare (with receiver) - same problem.
At this point, with minutes before the B Final was due to start and with the car now sitting dead on the bench, I decided that the only electrical component I hadn't changed was the motor. So I replaced it with my spare Top Models Missile 14Quad that I used to race back in the day and hasn't been rebuilt in 20 years. The car started up so I ran to the track to take up last place on the grid.
Due to a couple of cars suffering more problems than mine, I was actually 8th of 8 on the grid. I had driven nine laps in anger all day, was now using an unfamiliar transmitter with random settings and no idea if my setup was still appropriate for the track conditions. In the short drive to the grid I adjusted the steering trim on the transmitter to get it tracking straight and thought to myself that is seemed to now have as much punch with the Nimh packs as it had earlier in the day with the LiPos. Interesting...
As the race started, I hung back through the first corner melee and picked my way up to take 4th. Trying to find out how the car handled without making any mistakes I revelled in the newfound power increase and most ussefully the massive improvement in steering control - this transmitter/receiver combo had completely transformed the C2! Whereas I had assumed it was my rusty driving that caused me to struggle with fine control, it turns out that I could now hit apexes, hold slides and massively reduce the number of crashes. I had a tight midfield battle during which I recorded my fastest lap time of the day and was narrowly beaten into 6th spot by about 2 tenths of a second. I was elated to finally have finished a race, but even more so with the level of control I had found!
Needless to say, my mate is now lending me the Core RC 3 channel combo from that race. I will be refitting the LiPos and the Ansmann ESC for its next outing and will really see what it can do then...
Meanwhile, this evening I decided to conduct a post mortem on the old motor. Looking closely there was some seemingly innocent crash damage to the rear of the car:
The motor showed the endbell twisted and crushed into the can:
And internally there was plenty of carbon dust and evidence of contact with the magnets:
I suspect the damage to the motor caused it to draw more current and then the safety cutout from either the LiPo protector or ESC were kicking in. So frustrating!
Mind you, it was strangely satisfying to bolt in the pink missile motor from my youth and go racing in the thick of it again. This driver just got bitten by the competitive bug again...