Uk first efoil build - 65161 powered

[cpfoil]

I have been getting final parts together and am in need of some advice before taking a wrong turn on motor position to the mast to allow for the most appropriate prop diameter.

I see a lot of people are stearing clear of the flipsky prop (i have bought one with the motor) and opting for a smaller diameter prop. Should I fit the motor high enough to enable the larger 7 1/4 prop or equivilant options or drop it closer to the foil for a smaller alternative?

So far I have bought the following;
120kv 65161 motor
flipsky 75200 esc
flipskyvx3 remote
gong foil
200A smart ant bms

I was looking to build a battery from 21700 Molycel P42A. initially looking at 13s10p configuration. Is this sufficient?
Board wise I was looking to build a board from EPS over the next few weeks.

Any advice on the above would be greatly recieved and any pointers or links that may help me avoid too many costly mistakes

Thanks Chris

[Anatoly]

It’s better to have more alternatives! Attach it under this screw, you can always put a smaller diameter. And 2 cm is not a big difference! But this is my opinion!

[Anatoly]

I have a 21700 13s10p!More than an hour’s ride on the wing and 20 km of mileage! Your esc can run up to 16s!So you can also collect 14s!There will be more power! It’s up to you!

[Gazman79]

Hi Chris

I am in the early stages of my first build using the same components as you except a different esc.

I have opted initially to use the flipsky prop but cut down to 140mm, did some wet testing in fresh water and it pulls 135 amps at full power, initially I tried cutting it to 150mm but the amps were over 150 amps and at 12s (50v) was over the 6000w rating for the motor.

I’m no expert but you will need to cut down that flipsky 7.25x5 prop otherwise it will overload the system.

Please tell me if I have this wrong though.

Regards
Gareth

[Dynamik]

@cpfoil

or drop it closer to the foil for a smaller alternative?

I think the ideal is to place it as low as possible, but in such a way that it can accommodate not only a 140 mm diameter propeller, but also a 150 mm diameter propeller sometime in the future. For example, the Flite propeller is about 143 mm (https://foil.zone/uploads/default/original/3X/f/9/f9681b5e85d3654c87a43320bd710a3900a2302f.png), the top of the line propeller with two blades could be 150 mm.

[cpfoil]

Thanks all, thats a great help.
I will look to put the motor centerline around 80mm up from the fuselage and start with the turned down 140mm flipsky.
Battery cells and eps foam blocks now ordered, its getting to the serious bit…

[Gazman79]

This is how I modified my prop. First I made a balancing adaptor which was also used to mount the prop in the lathe, then I put a scribe in the tool post and rotated the Prop by hand and marked an accurate line. I then just cut the tips off with a saw and belt sanded to the line and rounded the corners.

[cpfoil]

Is there a reason you didnt use the lathe to turn the prop down?

[Gazman79]

I just didn’t want the cutting tool to catch and bend the blades with the intermittent cutting action,

It turned out nice, I also filled the area where the numbers are stamped and profiled the blade root to blend it in.

[cpfoil]

The prop looks great, I will look to try to replicate it.
Mast and foot machining for wiring and water feed now completed, making the hot wire cutter this weekend ready for some board shaping next week.

[cpfoil]

After getting some ply hot wire cutting profiles cnc cut, and building a series of hot wire cutters I had a good days board shaping and spreading polystyrene shavings around the neighbourhood. Left to do, get another template made for routing out the lip around the board and make an aluminium mount plate to bond into the base.

What is the best approach? long beams to spread the load further through the board or a wide tapped plate?
I had been considering rebating 2 lengths of around 1m long unequal angle (circa 1 3/4 x 1 x 1/8) then weld or bond some thicker blocks to tap into. Resin the angles in and glass over the top with a thick layer of cloth before wrapping the whole board in cloth and resin?

[Alexandre]

Nice , the way I see that , wide plated mount like I did if you can hold top and bottom together
Open case , better with long mount to spread load ( already done on forum , work nice )

[cpfoil]

Board reinforced with aluminium angle, getting close to encapsulating it. Before starting the grp stage, what do i need to do for receiver aerials etc.
I have the flipsky v3 remote with 1m aerial, what is the best setup for receiver can i leave the receiver in a plastic box, do i just rebate the front of the board for the antenna? I assume the gps module sits on the receiver, can the GPS work from inside the compartment?
Thanks Chris