Fr 2019 motor system

Gentlemen, results are in.
Constants: 100kg rider, whimsi 200L, Axis19 82cm mast. RL 2018 Foil. 14s8P Molicell 42p, trampa 75/300, flipsky 100kv, FR 6x6”.

  1. Reference: no cone.

  2. @nice2cu swirlcone


  3. @cim96dm7 short swirlcone, made with ceases prop desiner.

Conclusions:

  1. Its really nice to ride in the swedish autumn, when launching from dock and not getting wet at all.
  2. @nice2cu cone adds +10% energy use. It was also abit more nervous to ride with. Some drops of water also entered the cavity not helping witg balance. Anyways the vanes have to high pitch and are not shaped according prop design. This is the most likely cause. Correct it robert and I will ride it again😉
  3. I could only ride my cone for a short session and with low batt and also lower avg speed. Even if it shows some advantage avg speed is 4kmh lower then ref, so result can not be trusted. Also 1 vane broke when removing it, so 1mm vanes in ABS is on the weaker side, but it has same pitch as FR.
5 Likes

Hello Mattias!

Very good! I will correct it ASAP.
When you can test again?

Hi Robert,

Normally ride every second day, but prefer the lively ocean to the boring river…
Can test it in 2 days.
Try using

for base geometry to give some with to the bottom of the vanes and have them sharp at the leading edges.

2 Likes

just try to straighten the vortex, then you will succeed. Accelerating through too much pitch does not bring any advantages.

Since the resistance in water and air increases exponentially with speed the ”no cone” is the clear winner with the modest consumption at the highest speed.

It would be interesting to have a spinner cone without blades compared.

Do you think you keep the angle of attack and turning curvature and speed constant for three 7km runs? I must say it seems impossible. When you have ten repeated runs all showing lower consumption for a design then it is interesting to compare results.

Overall great effort, it’s better to test than to write on internet forums😀

Have you done some measurement on your setup Thomas?
What figures did you get with your setup?

interesting data here:

Some good things from this paper:

So i have to change my view on these, seems like a worthwhile addition when the rest of your system is mostly optimised already.

1 Like

Have this one from some days ago with plain cone. This was a joyride more so not in the name of science hence higher speeds.

You should get out and ride more than doing literature studies😉
I’m quite confident that i can keep close to identical runs.
I normally only differ 2w/km on the test track. I’ve done about 100runs there, altering props, wings etc.
However the most important factor is how high you ride and to keep that constant as well.

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Too many times myths are spread on forums, solidifying to ”facts” within time. We’ve all seen it so i always try to check what’s behind when i can.

And…
My board is busted and my better half is away so i cannot ride anyway… is it obvious😂

hello, in a few days i will be reporting on it again on facebook. Best regards

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During the wait for David to start making magic for the DIY scene i present another learning.
The frankenprop! I made some of these before joining the forum and getting my first FR prop.
So this is a solas amita, a quite good prop actially for outboards in 8-10hp range. Originally 7,8x7” But cut down to 6” diam and sharpened on the leading edges.
It’s been lying around a year now untested, so today I thought why not. Its more fun riding when testing something new or old. And since we’ve been exploring cones lately why not test something made for expelling exhaust gasses :blush:

It actually felt good running it but going above 30km/h it really became a frankenprop.

Still really nice to ride in swe, but not sure we will get our well deserved new FR:s before theres ice on the surface…

2 Likes

Mattias

I tested this afternoon, but failed for me
I need 60A for the take off and 35/40 after



I will try again with the FR propeller
when I receive it :wink:

I study in the last days some videos and documents about that cone with the small blades.
On your picture I see that the position from the small blades to the propeller blades are wrong!

Not only the position!!! Your cone creates reversed thrust

it seems obvious now that you say it
I didn’t even think about it after today’s bad results
i will modify this with fusion

:rofl::rofl::rofl:
Now I see it too :rofl::rofl::rofl:

Okay, my Spinner is fitting but I see also the position small to large blades is not korrekt.
But I think my Spinner have still a to large angel :thinking:

unfortunately I didn’t have time to test it
the wind came during the 1st test, I got back quickly to switch to a kite
I will test tomorrow or Thursday

Hi, this is the first time I see somebody actually testing my design on here. It warms my heart :slight_smile:
Sorry about the confusion about CW/CCW, the cone is only for FR:s and they are always CCW rotating.
As a general comment to you and @nice2cu, I do not believe the green support for the motor is needed. It will definately consume more than the possible gain of a cone anyways.

I can say the FR prop is fantastic, so I hope you get one soon. I have not been able to produce something within 10% of it in 10 trials, so I’ve given up :slight_smile:

1 Like

It’s my fault, too hurry to test :slight_smile: , I printed without checking the direction of rotation
and I had not seen that the FR propeller is CCW
And I didn’t even see it when I installed it :slight_smile: :joy: :crazy_face:
I unterstand now the 60A for the take off :slight_smile: :slight_smile: