For who try/have tried direct drive with outrunner

I forgot to mention that i did try a bunch of prop and test power draw on each and just did a crude hand held thrust assessment.

the 3D printed props did well IMO and the best one i made perfectly smooth and out of PC MAX a poly carbonate 3D print material which was super strong / stiff.

I also purchased a FR 6" pitch prop for comparison as well and tried that. Its a work of art and definitely gave me more efficiency, more top end speed and more thrust than my best 3D printed prop.

The FR is expensive vs printing something for almost nothing BUT with all the effort we go to to get out of the water and the power we put into the motor i cant see the point in running printed parts when there is so much to gain from a proper machined part. IMO and testing anyway.

but it way a lot of fun to play with printed props. that all being said the printed prop would be safer for learners as it has a very rounded LEdge



How much does the FR prop cost?

this is from their web page.

but he gave me some extra % off as i bought 2 motor systems as well.

its a beautiful prop and IMO worth the $


@rcjetman: what is the kv of your motor ?

It’s so old 6+ years I can’t remember. I think 170kv

My hypothesis is that the surf program of your foil has some responsability in your max speed (designed not to be faster than a 3 foot wave) and acts as a open parachute passed 16/18 knots.
Curious to know what are:

  • your speed at 80 and 100% throttle ?
  • the max thickness of your front wing and stab ?
  • the max chord of your front wing and stab ?
  • your mast thickness ?

I have the “old” FL propeller , 3 blades , i don’t known if the design (pitch…) had change but i was not able to get more than 3100rpm ( small motor geared) , which is about the same here , 80-85% of a 6s with “170kv”
Have you measured the pitch?

Yer I’m not chasing speed atm more so just a nice satble setup for riding waves that dosent go too fast as a waves energy once caught is like a TURBO boost that doesn’t stop. In fact once in front of the wave I reduce throttle or somtimes I can even foil with 0 throttle and the wave has so much power it overides the drag of the motor.

I have two wings. Axis 102. And the 82

I have tried both and as u would expect the 102 has more.lift and gets out of the water much easier. Uses less power and is more stable. Conversly the 82 has the opposite aspects vs the 102 but did not increase top speed much and i thought it was going to be more.

102 wing 20km max speed. 80% 17 km
82 wing 23 km. 80% 19km

82cm Wing Technical Data:
CHORD: 222.7mm
ACTUAL AREA 1528 square cm / 236 square inches
SPAN: 82 cm / 32 inches
PROJECTED AREA: 1443 square cm / 223

102cm WING Technical Data:
CHORD: 250cm
ACTUAL AREA: 2051 square cm / 318 square inches
SPAN: 102 cm / 40 inches
PROJECTED AREA: 2013 square cm / 312

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He tells me.its a 6" inch pitch. I have the 7" pitch props coming on my FR motor setup so I will play with both when it arrives.

Probably the new design for direct drive , don’t recall exactly but i measured at the time a lit less the 9" on mine , maybe @Flying_Rodeo can confirm ?