Carisma F14 Blog - Part 6
In part six of the Carisma blog we're focused on selecting a brushless system for the F14.
Running the GT14 brushed motors in the F14 was a real handful, not only was it way too fast, especially on the kit rubber tyres, but the wear rate on the brushes meant I was replacing them every other meeting, so they had to go. Brushless is the way forward, but in such a small model the usual question is "what to fit?"
The Carisma 4500Kv brushless sensorless motor and V6 'S Type' ESC are a perfect match for the F14, quick enough to be thrilling, challenging, exciting and yet still very drivable, efficient and reliable.
V6 'S Type' Carisma Brushless designed specifically for the F14. The 4500Kv brushless motor is plenty fast even for the biggest circuits.
Despite being sensorless, a properly set up direct drive F1 car means there is minimum cogging, once the overall gearing is brought into the realms of sensibility, usually so low that even very slow movements are possible from stationary without hesitation, and lining up on the grid, or indeed getting away from it, is not a problem anymore.
The built in delay between forward/reverse direction changes eases pressure on the driveline and allows you to brake very hard without fear of spinning the wheels backwards ? which usually leads to suddenly exiting the circuit at a tangent.
Reverse can be disabled with the press of a button, the same button that helps set your end points, and apart from that it is ready to go. Typically I cut off the huge Tamiya type power connector and replaced with my favourite, the 3.5mm short stubby gold tube connectors from FTX. The Carisma V6 ESC has nothing to adjust, or programme, so nothing to worry about, just plug and play.
The overall size of the ESC means it goes straight in the F14 no problem, and the motor likewise is a snug yet comfortable fit in the rear pod so long as you carefully bend the three power wires up close to the end bell.
The 2mm motor shaft accepts the kit pinions, and it has a flat to help retain the grub screw properly for extra reliability. Ball races on the motor shaft keep things smooth, fast and efficient as you?d expect. The virtually maintenance free design of a brushless combo means you won?t need to do anything more than change the gear ratios to suit the size of your chosen race circuit.
The optional Carisma Gear set adds 16, 14 and 10 tooth pinions to the kit 12 tooth.
I found the delay between direction changes a little frustrating when in a hurry, because you also have to hesitate at neutral in order to go from reverse to forwards, so when backing out of an incident there is a definite pause, which seems an age when you are mid race but in reality is just a fraction of a second. Most ESC's allow you to go directly from reverse to forwards, but not this one, it thinks you are braking while reversing and refuses to go forwards until you have returned the throttle to the neutral position, hence minimising the chance that you will strip a spur gear or spin the tyres in your haste to get away from a silly mistake.
Off the grid at the start of a race there is no hesitation which is excellent for a sensorless brushless system, so even from pole position I could make great starts and always be first into turn 1.
All fitted nicely with enough flex in the motor wires to not upset the rear pod flex.
A 4500Kv motor might not sound fast, but even geared down as far as it would go, (10/80) and on the biggest track I could find (Ardent Raceway near Derby) the F14 never felt under powered, and I could not have used any more speed without risking a very big crash indeed! I might gear up but only to tame the acceleration slightly on very wide open smooth layouts, just slightly, because as it is I really like being able to use the throttle and brakes to sharpen turns, in true 2WD style. The same gearing on a much smaller indoor club like Bedworth indoors was just a little too fast but easily handled without having to resort to transmitter endpoint adjustment and such like. Even on this tight twisty circuit, at the end of a 5 minute race I could hold my lips against the motor and ESC likewise, it was running that cool, around 45 degrees C, so I knew everything was happy and running well within their optimum parameters.
Don?t be tempted to fit a faster motor in a little F1 car, it will just upset the handling and lead to faster mistakes, I?ve proved over the past three months that a sensible motor can win races, repeatedly, while those around me are limiting their throttle end points, driving extremely carefully and still suffering thermal cut out before the end of a 5 minute race. They?ll figure it out eventually, and then I?ll really have a race on my hands, I can?t wait!
V6 'S Type' Carisma Brushless designed specifically for the F14. The 4500Kv brushless motor is plenty fast even for the biggest circuits.
Despite being sensorless, a properly set up direct drive F1 car means there is minimum cogging, once the overall gearing is brought into the realms of sensibility, usually so low that even very slow movements are possible from stationary without hesitation, and lining up on the grid, or indeed getting away from it, is not a problem anymore.
The built in delay between forward/reverse direction changes eases pressure on the driveline and allows you to brake very hard without fear of spinning the wheels backwards ? which usually leads to suddenly exiting the circuit at a tangent.
Reverse can be disabled with the press of a button, the same button that helps set your end points, and apart from that it is ready to go. Typically I cut off the huge Tamiya type power connector and replaced with my favourite, the 3.5mm short stubby gold tube connectors from FTX. The Carisma V6 ESC has nothing to adjust, or programme, so nothing to worry about, just plug and play.
The overall size of the ESC means it goes straight in the F14 no problem, and the motor likewise is a snug yet comfortable fit in the rear pod so long as you carefully bend the three power wires up close to the end bell.
The 2mm motor shaft accepts the kit pinions, and it has a flat to help retain the grub screw properly for extra reliability. Ball races on the motor shaft keep things smooth, fast and efficient as you?d expect. The virtually maintenance free design of a brushless combo means you won?t need to do anything more than change the gear ratios to suit the size of your chosen race circuit.
The optional Carisma Gear set adds 16, 14 and 10 tooth pinions to the kit 12 tooth.
I found the delay between direction changes a little frustrating when in a hurry, because you also have to hesitate at neutral in order to go from reverse to forwards, so when backing out of an incident there is a definite pause, which seems an age when you are mid race but in reality is just a fraction of a second. Most ESC's allow you to go directly from reverse to forwards, but not this one, it thinks you are braking while reversing and refuses to go forwards until you have returned the throttle to the neutral position, hence minimising the chance that you will strip a spur gear or spin the tyres in your haste to get away from a silly mistake.
Off the grid at the start of a race there is no hesitation which is excellent for a sensorless brushless system, so even from pole position I could make great starts and always be first into turn 1.
All fitted nicely with enough flex in the motor wires to not upset the rear pod flex.
A 4500Kv motor might not sound fast, but even geared down as far as it would go, (10/80) and on the biggest track I could find (Ardent Raceway near Derby) the F14 never felt under powered, and I could not have used any more speed without risking a very big crash indeed! I might gear up but only to tame the acceleration slightly on very wide open smooth layouts, just slightly, because as it is I really like being able to use the throttle and brakes to sharpen turns, in true 2WD style. The same gearing on a much smaller indoor club like Bedworth indoors was just a little too fast but easily handled without having to resort to transmitter endpoint adjustment and such like. Even on this tight twisty circuit, at the end of a 5 minute race I could hold my lips against the motor and ESC likewise, it was running that cool, around 45 degrees C, so I knew everything was happy and running well within their optimum parameters.
Don?t be tempted to fit a faster motor in a little F1 car, it will just upset the handling and lead to faster mistakes, I?ve proved over the past three months that a sensible motor can win races, repeatedly, while those around me are limiting their throttle end points, driving extremely carefully and still suffering thermal cut out before the end of a 5 minute race. They?ll figure it out eventually, and then I?ll really have a race on my hands, I can?t wait!
Dez Chand
Click the images below to view the other parts of the blog.
