Its really nice to ride in the swedish autumn, when launching from dock and not getting wet at all.
@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😉
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.
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😀
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.
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
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!
Hi, this is the first time I see somebody actually testing my design on here. It warms my heart
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
It’s my fault, too hurry to test , 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
I unterstand now the 60A for the take off
