The biggest difference is the cutting mat and the circular blade! Trust me!
This is a few bucks on Ali or you can get in the dollarstore in the sewing area. Those work fine aswell
Just wet the cloth and you can easily cut with a normal scissor.
Also prevents fraying fibers afterwards or moving of single strands.
Circular blade is ok for small amounts, but get’s dull pretty fast, if you cut more.
Looks like you could make good use of a third arm when putting out that parawing while pumping, holding the remote, the camera and the parawing bar 
Great to hear that the motor is performing 
The silicon putty I was waiting for was delivered so I finished up the build:
- sealed the antenna compartments with silicon putty
- potted the electronic with magic gel → 250 g of magic gel
- put glue on every screw
The complete unit with battery is at 3.57 kg. The prone board is at 3.61 kg. I think I will land somewhere between 9 and 10 kg as the Gong Material is not the lightest out there.
Here the sealed antenna compartments from the top, one for the remote and one for vesc express.
And here from the bottom. The reception plate pushes against the silicon from the bottom (about 2mm of compression). The mast on top is holding against it.
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Foil Drive is now showing peak and sustained power outputs for their units in the tech specs. And also the thrust specs.
Slim and Max have the same power output. But the Max has higher thrust.
Slim:
Max:
This one is the Fusion and is 12s:
To reach those peak power outputs with an empty or full battery would require battery amps of:
Fusion (2155 W)
Full battery (50.4V): 42.75 A
Empty battery (36V): 59.86 A
Slim/Max (1854 W)
Full battery (46.2V): 40.13 A
Empty battery (33V): 56.12 A
And for sustained power outputs:
Fusion (1750 W)
Full battery (50.4V): 34.72 A
Empty battery (36V): 48.61 A
Slim/Max (1455 W)
Full battery (46.2V): 31.49 A
Empty battery (33V): 44.09 A
It is interesting to see that they are limiting the Max and Fusion compared to the Slim pretty hard. The Slim battery is a 1P, the Max has 2P and 3P batteries and the Fusion has probably 4P I guess.
Also what is interesting that despite the same motor and power output the Slim has less thrust than the Max. It seems like they are artificially limiting the Slim on the VESC side. Probably by phase amp settings?
The question for those power output numbers is, are these numbers mechanical power output at the prop or electrical power output? If it’s mechanical, then the battery amps are even higher. This would also mean our units are more likely comparable to the Slim/Max units regarding power output.
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What aluminium did you order them from? AlSi10mg or Al6061? 6061 would be stronger and more resitant to salt water but more expensive and prone to cracks. AlSi10mg is better to print fine structures but a bit less strong and hard to machine.
I think I‘ll go for AlSi10mg.
I could test the assist today. The good news is, it did not burn down. The bad news I could not get up. Something is limiting my power.
The complete setup is at 11.5 kg, while the mast and foil make up 4.3 kg. I ride the Gong HM mast in 77 cm, titanium fuselage (which is heavier than the alu) and Veolce H XXL (1300 cm^2).
In my config I have set the power limit to 2100 W. But I reached only 1432 W. I will dig deeper if I can find some logs. Otherwise it will be trial and error.
Regarding the antenna. The reception is very weak. I really have to hold the remote next to the antenna. 30 to 40cm away I loose the connection. So I also need to improve this.
What is your max phase current setup? That could be the limiting factor as you need a lot of torque to accelerate. You only get max wattage if you can reach a certain rpm level. Bigger foil/ board, prop with less pitch or more current would help.
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I have max phase current set at 100 A and abs max at 150 A. It might be too conservative. The battery amps are set at 45A.
Per spec the 75100 is allowed to have 120 A. How far above the spec can I bump this up?
That is the issue.
My guess at least.
Is that the max your battery can deliver, even for bursts?
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Those are p42a and speced at max 45 A. So I did put it as max battery current. Do you think I could go higher?
But 43,2Vx45A = 1944 W
Fully charged it should deliver above the 2100 W limit I have set up.
My guess would be phase amps too low, need 125+ phase amps.
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If max phase amps in the run was 80A, why should raising that limit help?
At least efficiency, you’ll see phase amps at double your battery amps. I always set my phase to 140 and battery to 90. That way I have a bit of headroom. I’ve found I got 80a and 140a phase on a deep water start with a 24L board.
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Do you have these battery amp settings on a 1p battery?
I probably should test it with the downwind board next time and see which power I can reach with that board.
Might it also be due to the prop? I currently only have that 2 blade prop (Propellerking Fold)
I have battery at 50a and phase at 140A (only need 120a with 120kv 6384) if your battery current is not maxing and rpm are low compared to unloaded, means the motor is not producing enough torque to spin up the prop. Non-vesc esc usually do not have any phase current limitation, leading to the common misconception that vesc is less powerful.
Prop also matters of course, some will require more or less amps to spool up. Motor kv is also very important, lower = more torque per (phase) amp
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Okay, I fixed the logging now. So next time I will have more data to look at. Took me a while to find out all necessary settings to make it work 
My Motor has 130 Kv and the prop is a two blade with 165 mm diameter and 5" pitch.
With higher Kv the motor needs higher phase amps to reach the same torque. In ideal conditions for BLDC the equation is:
T [Nm] = Kt [Nm/A] · I_phase [A]
with:
Kt [Nm/A] = 9,5493 / Kv [RPM/V] <= simplified
120 Kv and 120 phase amps => 9,5493 Nm
130 Kv with 120 A => 8,81 Nm
130 Kv with 100 A => 7,35 Nm
130 Kv with 80 A => 5,88 Nm
The motor needs 130 phase amps to get the same torque. But it has not reached even the 100 phase amps yet. The next logs will show what really happens I hope.
@Jezza you are setting 140 phase amps. Do you have a 140 Kv motor coincidentally?
I had to rip up the magic gel to change the sd card. Did your magic gel heal completely or should I add some fresh gel? @Bzhwindtalker
That’s great. Your project is a huge help to me. Where can I get folding propellers for the 5085?
Good news, today the motor delivered over 2.3 kW of power. The only two things that changed were the updated firmware and ERPM limit bumped to 35.000. From the logs the motor usually was below 20.000 ERPM, sometimes at around 22.000 and once jumped to 27.000. The limit before was at 22.000. I do not think the updated firmware itself made it work, but maybe it wiped a wrong config value.
The battery current gets fully used, sometimes at 50 A (limit at 45 A). The phase amps were between 80 and 97. I later bumped the phase amp limit but the motor does not reach more. But the duty cycle stayed somewhere between 0.6 to 0.68. So this will be limited by the battery as you said @Jan12 and @Jezza
So now it is just a skill and remote connection issue. I was able to stand up a few times but then the remote connection got lost and the motor stopped. Need to get this fixed first.
Next time I will try the wing foil (75L) or downwind board (120L) to get a better feel for the assist popup. Also I will upgrade to a three blade prop. After that I will decide If the next battery will be a 1P oder 2P. RS50 cells are already here and are waiting to get used in a battery pack
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@Bzhwindtalker is your external antenna cable attached directly to the receiver or is it kind of passively extending your internal antenna?
I am thinking of getting a 5cm ufl cable which would connect to the receiver and on the outside to the reception plate directly to the external antenna. This way the external antenna can stay mounted on the board.
There is no connection between both antennas, they just need to be close together with no water inbetwee, it works very well (suggested by @rttn )
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