ESC inboard or outboard?

[David Hall 9]

I've yet to fly any fixed wing and have a very nice looking Phoenix 2000 kit on my shelf (too nice to relearn FW with). I'd wondered about something a little more appropriate for my "comeback" to RC and also discovered that my grandson might like a go, at least someday. With this in mind, I bought a Bixler 1.1 ARF (if it survives my uses, it could be handed on to the grandson) .

Reading various threads on the Bixler v1.1, it seems that the build involves fitting out the servos, ESC and motor within the fuselage halves, then permanently glueing the two halves together. Very odd way of building!

So, some people seem keen to mount the ESC on the outside, to get better cooling. I have a cheap Hobbypower 30A ESC. Should I be thinking of outboard mounting for better cooling (& for replacement if it's not too good).

Any other tips before it all get entombed?

 

 

Edited By David Hall 9 on 04/02/2016 16:24:25

[David Hall 9]

I should add that the kit includes a 2620 1900KV motor. It recommends a 20A ESC and 3S battery.

[Dave Hopkin]

I've never seen any of the Bixler range with an external ESC, a 30A ESC on a Bix doesnt generate much heat so put it inside, but ideally where it can be removed if required

[Geoff S]

I don't like building in any components that may need replacing or, at least, some attention. It just goes against the grain for me.

However, when I electrified my Limbo Dancer it was easier to fit the esc outside the fuselage in a safe place between the undercarriage legs. I have to take the wing off to replace the battery so I put the battery connectors through holes in the fuselage bottom which means I can replace the wing without the battery connected. It's an ugly model anyway so looks aren't an issue and motor is exposed anyway. It certainly keeps cool.

Geoff

[Martyn K]

I put the 80A ESC for my F3A in the exhaust tunnel. Mainly to try and keep it cool

Martyn

[Simon Chaddock]

David

It is perhaps worth remembering that the ESC does produce some heat so it is a good idea to carry it away as you fly. Obviously if it is totally enclosed in a small well insulated space it will just get hotter and hotter until it either shuts down or fails.

In most cases just ensuring there is a positive airflow over it is adequate, indeed the thermal properties of the shrink wrap around it is more of a limiting factor to the rate of heat transfer rather than the velocity of the air passing over it. This is why bigger high current ESCs normally have their heat sinks 'open' to the air flow.

The total quantity of heat generated is proportional to the battery capacity but the rate at which it is it is produced will depend on the flight time. Obviously it is easier to dissipate the heat (so it remains that bit cooler) in say a 15 flight than if you use up the same battery capacity in just 3 minutes.

[David Hall 9]

Thanks All for your help,

The ARF kit arrived today. I'm quite impressed by it.

The motor leads are short, so that the plug-in junction with the ESC leads end up inside a channel which is permanently sealed when the fuselage halves are joined. The simple fix (I guess) is to extend the motor leads by a few inches so that I could get at them should I ever need to replace either the motor or ESC.

For the first flights, I will leave the ESC inside the fus.