Motor Recommendations for 95mm 4 blade Prop

[Batfish]

Hi, all

Looking for recommendations and links to a suitable motor
Looking to turn a 95mm prop, which will be on the back of a 1/50 Zwarte Zee

Would it be worth considering Brushless??

Many thanks
Adam

[Calimero]

Robbe as a nice slow brushless outrunner in their Roxxy range: 5055/45 100kv. They recommend it for their 95mm prop instead of the good old "Power 1000" brushed motors (like I have in my Odin).

Under 12V that would be 1200rpm (no load) which should be fine.

Problem is that they're a little pricey: around 100E.

HobbyKing has two big motors around 200kv which you'd have to run obviously at 6V:
http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=51869&aff=1225438
http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=19039&aff=1225438

My springer already has a BL motor. I'm thinking about retrofitting my Odin with a brushless motor... Motor was installed 15 years ago but I only launched her this year.

[Batfish]

Some good information there thanks.

Did someone not say the Brushless motors needed sensored esc
As slow speeds is a problem with some of the available Esc?

Brushless is the way to go, perhaps prices will come down as more people start using them.

[Calimero]

Some good information there thanks.

Did someone not say the Brushless motors needed sensored esc
As slow speeds is a problem with some of the available Esc?

Starting a boat or plane prop doesn't require that much torque.

Sensored brushless motors (and ESCs) are required for example on "rock crawlers". Or if you're building a winch. In those situations a brushless motor can "slip" and without a sensor it could probably end up "stuck".

Brushless is the way to go, perhaps prices will come down as more people start using them.

Slow BL motors aren't very common or end up way too big because they're geared toward big (huge) RC planes. But even if the motor is 70-100EUR I'd still go the brushless route.
Ease of installation, reliability in the long run, efficiency ...

[Batfish]

So would it be worth purchasing an rc car esc or is it best to go boat esc and water cooled???

[Calimero]

For scale boats, RC car ESCs are the way to go.

We've used the following successfully:

HobbyKing® ™ Brushless Car ESC 45A w/ Reverse

Turnigy TrackStar 1/10th Scale 60A Car ESC Version 2

mengam (another French member) is using the former - or maybe its 60A alter-ego available for a few extra dollars - in his Hunter tug while I use the latter in my springer tug.
Once programmed (ie: remove the brake feature to have "direct" reverse) they offer very smooth throttle control. With slow BL motors you should be able to get down to less than 100rpm.

[Batfish]

Would a rock crawler esc be the way to go?
Forward and straight into reverse without braking.

There is a motor that I was going to go for low Rpm but it is recommended a 90amp esc is used.

Regards
Adam

[Calimero]

Would a rock crawler esc be the way to go?
Forward and straight into reverse without braking.

Check the links I posted above. They can be programmed to disable the brake and go straight to reverse.

There is a motor that I was going to go for low Rpm but it is recommended a 90amp esc is used.

Even with a 95mm prop you won't reach such figures.  90amp is when swinging a huge airplane prop.

[Batfish]

Thanks Bud,

I have 2 scooter motors here that I was going to use in another Tug build
But after the information from yourself and the availability of brushless, I'm going to use 1 of the scooter motors in the big tug and use Brushless twin screw setup in the other tug/ mostly for towing, the props on this tug are 70mm steerable Korts.

Thanks so much for the information.

Regards
Adam