Model Boat Mayhem

Technical, Techniques, Hints, and Tips => BRUSHLESS Motors and Speed Controllers => Topic started by: mmartin1980 on November 12, 2021, 11:26:58 pm

Title: watercooling
Post by: mmartin1980 on November 12, 2021, 11:26:58 pm
Hello all, would a coil type cooler work just as well as the sleeve type one as ive just jerry rigged all the cooling up ti see how well the water pump works and the sleeve one (that came with the motor) leaks so bad i may as well just submerge the motor lol


a coil one would mitigate the leaking problem, just wondered if they are any good as all the adverts for them say there for brushed motors and mines brushless
Title: Re: watercooling
Post by: derekwarner on November 13, 2021, 01:49:57 am
Water cooling of small electric motors is a complex matter involving the transfer of heat from a source to another medium


Specific heat transfer of metals is a huge influence, together with water and air [literally] intermingled


If you have a jury-rigged setup, run the motor load until it is hot, feel the motor casing [$15.00 digital laser is helpful], connect the cooling water supply & repeat the same test


If the cooling water discharge is warmish, then you certainly have provided a means of cooling the motor internals


Both brushed and brushless motors can experience a significant heat as generated from the product of work


Most of the direct slip-on motor shell coolers with o-ring sealed ends appear to be anodised aluminium, some appear that the anodisation is an external process, with raw metal internals....so you would need to understand any potential reaction between your cooilng water and both the motor external sleeve and the internals of the sleeve cooler


I could only suggest you talk with some high powered brushless boat builders with onboard cooling, and work backwards from there


Keep us posted with your results


Derek
Title: Re: watercooling
Post by: derekwarner on November 13, 2021, 04:45:03 am

Following is a link to a water cooling system  %)  of a model boat motor.........which may be of interest.


https://www.modelboatmayhem.co.uk/forum/index.php?action=dlattach;topic=67483.0;attach=216670;image
Title: Re: watercooling
Post by: gra2 on November 13, 2021, 08:05:19 am
As long as your brushless motor is an inrunner the coils should assist cooling.

Graham
Title: Re: watercooling
Post by: Fastelectrics on November 13, 2021, 08:33:34 pm
I have used coils on my fast electrics and they work well. To get a good transfer of heat smear the motor case with heatsink compound.
Title: Re: watercooling
Post by: mmartin1980 on November 14, 2021, 12:16:31 pm
cheers people, I will go with the coil... i had images that the first time i use the boat there would end up being more water inside it than under it lol
Title: Re: watercooling
Post by: ChrisF on November 14, 2021, 07:27:14 pm
Before you do that is the motor an inrunner or an outrunner? As Graham says with an inrunner you can use a coil or the aforementioned sleeve but with an outrunner you can't as the outer casing of the motor spins!

Another option is to use a water cooled motor mount.


Also most folks who water cool don't use a pump but use the forward motion of the boat to circulate the water. I think using a pump can get a bit complicated.
Title: Re: watercooling
Post by: mmartin1980 on November 14, 2021, 08:17:55 pm
its an inrunner motor so i know the coil would be fine, only going with a pump as i have a little 3v one lying around, just enough pressure to flow it around the system nicely
Title: Re: watercooling
Post by: Colin Bishop on November 14, 2021, 08:29:48 pm
Do you actually need watercooling? It should only  be required in high speed applications where you are really loading the motor beyond it's normal limits.

Colin
Title: Re: watercooling
Post by: mmartin1980 on November 14, 2021, 10:41:44 pm
i think it comes down to the old saying---- have it but dont need it instead of need it and dont have it