Hi. I am building a 35" version of the aerokits RAF fire tender. I am at the point where I need to decide on the electric motor which is appropriate. I would like the vessel to be able to come upon to the plane without to much effort and have a bit in reserve for anxious moments or sheer fun. Do you recommed a brushed or brushless motor and if so what power rating. If brushless either in runner or out runner. Grateful for any advice. Regards Kevin.
Hi Kevin, I would recommend a brushless motor, and have great success with Airtec motors, real model shop with real people on the end of the phone. The one i would use is AXP 3542/1000. They recommend a 60 ah ESC but i would up this to 90 or 100, just in case of a fouled prop etc. Just type in Airtec Hobbies its all on there website
I have had a lot of success with Tornado Thumper out runner motors paired with Fusion Hawk ESC. For a really exciting performance you could use a Tornado Thumper V3 4260/06 500KV - Brushless Outrunner paired with a Fusion Hawk BL 60A HV N6~18/Li 2~6 ESC, however it would probably be a little less exciting and more appropriate given the flatness of the hull when the Crash tender is on the plane to use a Tornado Thumper V3 3542/05 1250KV - Brushless Outrunner paired with the same speed controller. Motors are available at https://www.overlander.co.uk/motors/brushless-motors/outrunn... https://www.overlander.co.uk/motors/brushless-motors/outrunner-motors/tornado-thumper-v3-4260-06-500kv-brushless-outrunner-rc-motor.html and the speed controllers at: https://wheelspinmodels.co.uk/i/85116/ I appreciate they are not the cheapest of options but I have found their reliability to be second to none.
I' doing somehthing very similar, rebuilding one from the 60s, when I get time to finish it. I picked up a Brushless outrunner, Robbe/Roxxy Outrunner 4240/10 - is this about right? - Will it be OK with a 4S/5000mAh lipo? - What prop would you suggest to start with?
Looking at the specs ROXXY BL Outrunner 4240/10, 980rpm / Volt, 130g For electric sailers up to 4500g Scale and sport models up to approx. 2900g. If you have the 34" Fire Boat then this is too big. Mark suggested above a 3542/1000 and I agree. The smaller model is very light with a small transom and I found it has tendency to lean under the tork effect of the prop. Turning had to be slow and gentle to avoid capsize. This is not such a problem on the 48" version. Props should be no greater in diameter than the motor and should be chosen to keep well within the motor and ESC ratings. A wattmeter will help you check this and a good rule of thumb is to run at about half max current for best results.
Thanks Dave, yes it's about 34". Complete novice at this, so any help is much appreciated. I didn't find the specs you found when I was looking. Guess I'm going to be finding something else to do with the motor.