I performed a full throttle long run test on the twin 50mm EDF system for the Saab. Hooked up to a 2200mAh 45C pack. It lasted just under 1min 50 seconds before performance drop/empty battery at full throttle. Pulled around 65amps continuous out the pack peaking at 70 amps. Sat around 650watts most of the time peaking at 670watts sometimes dropping to 640. The pack got quite warm and seem to expand slightly – a bit worrying as its rated for 99 amp continuous and 199 amps peak. Need to test a few more times.
A successful test run of the power system for the Saab 105:
- 2 wemotec 50mm micro fans
- 2 Hobbywing Flyfun 40 amp escs (aka pentium)
- Castle 10amp BEC
- Turnigy nano-tech 2200.
There are 3 runs recorded, didn’t have the camera on for the very first run as I was checking for clearances. It pulls around 62-63 amps / 630-660watts at around 10v on the 2/3rd run.
Need to fine tune the balance of the rotors then dynamically balance the rotor with the motor using my mobile phones accelerometer – excellent guide here on RC Groups.
Motors, esc’s and new Spektrum AR7610 assembled in the test stand while waiting for the batteries to charge before a test run. Adjusted the second throttle to run on AUX2 or channel 7. This will allow fine tuning / balancing between left and right throttle.
Test fit 50mm wemotec in the motor mount with the dons rc motors mounted. The two wemotec housings are not 100% anymore after trying to get the het motors working in them so I’m going to get some new ones before proceeding with the build.
A quick test run – got some resonance and rubbing on one housing that needs to be sorted – this is just under halfway up on the throttle:
I was very disappointed with the quality of the HET motors I got for the Saab. Imprecise engineering lead to the mount holes being off centre. Additionally there was a lot of play in the motor shaft resulting in noticeable movement off centre when installed in the wemotec micro fan. Running resulted in scraping at certain parts of the throttle curve.
I’ve replace the HET motors with donsrc.com 6000kv. Build quality is excellent mounts are true and there is no slop at all when mounted in the micro fan housing. Next step will be to test run them.
I’ve added images of all the cars that are still in one piece – more or less:
Carrera Jeep – chassis ok, body some wear, drive train – toast needs new diff gears
Kyosho Spider EP – chassis worn, body new, drive train – toast needs new belts, gears, steering
HPI Micro RS4 – chassis ok, body ok, drive train ok – motor need replacing and a good smooth track to drive on
Team Associated RC18B – chassis good, body good, drive train overstressed – too much power!
Tamiya Lunchbox – chassis funny, body scratched, drive train over powered with brushless – custom rear suspension with 3 dampers and a brushless motor on 2S – wheelies ahoy!
Losi Micro-T – chassis ok, body ok, drive train ok – good fun indoors
Losi Mini SCT – chassis new, body new, drive train new – RWD fun very quick out the box on 3S
Losi Micro Rock Crawler – chassis new, body new, drive train new – good fun in doors!
HPI Vorza Flux HP – chassis scratched, body good, drive train good – 6S = fast 😀
Hopefully I’ll be able to get back to building the Saab 105 soon workshops still in a bit of a state
The good folks at HPI have replaced my busted Vorza motor under warranty. Time to charge the battery up now we’ve got some mild days coming!