Newcomer's build [Ger] + 2nd one

Hi,

I have chosen the 120kv for second build since I want to see how FR prop performs with this. At 12s with 100kv it’s speed is kind of limited early. In my opinion the right prop for your motor comes out of the printer. I think both motors can perform similar, just a matter of pitch and diameter. Bottom line:If you want FR prop go with higher kv motor.
For the foil: I just got the pro M wing. I have learned on rise L which was good. Now I am looking for some more Agility, maybe I will try the new wing today and share my experience

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Okok, I tried today. In my log you can see a branch to my local river. This is like habour exit, there is no natural flow. I do my speed runs there to have comparable results. The prop is always the same, quite a big two blade with high pitch. I have two speedrund:
1st with Rise L starting around 18:04:22
2nd with Pro M starting around 18:16:44

Top speed is more or less same (38km/h) but battery current differs around 10amps. Besides the lower consumption the pro m wing rides much more agile (beginners would say unstable :slight_smile: ) however, I need more time and power to get out of the water and the overall “basic speed” is definitely higher. With the this prop and wing my setup is finally where I wanted it to be.

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What pitch and size is the prop?

172mm Diameter, 182mm pitch

I assume your actual RPM is a half or a third of what is shown?

Erpm is shown. I think you need to divide by pole pairs (/3)

What do you use to get this type of logging data, the metro pro transmitter? Is it plugged into your esc?

Two times yes
20charrrr

So there’s a bit of an issue here. Some of the numbers are actually impossible as they are resulting in a negative prop slip. To me there looks like there’s something that’s not quite correct.
If you have access to a Garmin watch, maybe log your speeds with that and see if they differ to the metr app. Here’s a simple calculator to help with prop slip Prop Slip Calculator | Mercury Racing

I am pretty sure about the speed since I also have a 2nd mobile “on board” with different gps based logger. Maybe the pitch of the prop is higher, I do lots of copy & paste in tinkercad and lost in files and their names. Or: due to the gfk on the blades he is actually faster then I raw printed version. Which exact data point caught your attention? Btw thanks for checking my log :slight_smile:

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Update
Finished propulsion unit. I did some bad mistakes with mast drilling which I did not had at first unit. What is this called? Lesson unlearned :sweat_smile:
Also woodbox is done, I need to cut the board now

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I had some overcurrent issues with the new propulsion unit tested on my 1st board. It’s 120kv motor and 80cm mast (the other one is 100kv). Could fix it with help of @Giga and @superlefax. I almost always had a cut off at start. Putting the abs to 180 amps helped.
New log from yesterday (@michion. You can find my rpm here).

Regarding to your log it looks like you haven’t maxed out your propeller dimensions yet. You are running at 95% duty cycle. Which prop are you using now?

You still can raise the pitch a bit more to achieve more than 40 km/h :facepunch:

I like your attitude, it’s like mine. This is FR prop. I am looking forward to test my printed 7" two blade prop on the 120kv. This prop gave me already 38km/h on 100kv motor, so it will be very fast on 120kv. It’s just the question if I am able to get out with it

Comparing logs it looks like the pro M takes 20amp less at full throttle compared to Rise L. This behavior is same for both of my propulsion units (100&120kv).
I have a log but no speedrun on this. Ms Efoil was using most of the juice and I prefer to perform test run with full batt at start…

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Speedrun Gong Pro M + Pro Stab, 12s, FR prop, 120kv Flipsky (ceramic sealed)

16:16-16:18

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Which motor was this with?
*Sorry I just seen now the 120kv.
Which prop?

Sry, updated. See top

About the builds, first get together of both slides

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You riding a tidal river? One direction seems slower than the other…

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