Thanks for that. What printer do you use?
Any chance you could share your cad model… I wouldn’t mind trying to make it taller and house the batteries??
Could you also post a photo of where your batteries are hidden?
@tosh.jah …would a 2x 6s2p fit in this box side by side with the the battery’s length side up ??.. in short, 71mm (length of battery) instead of the battery diameter of 21 mm (x3) as you’ve gone with your setup. The internal.measurement of the Bopla box you’ve used is 82mm from bottom of box to inside of lid and it seems like this pack configuration would work also.
What you think?
Cheers
Marks
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I went for Polyd which was cheap in professional MJF printing UV Mechanical.
I would not suggest to host batteries in the same area than the controller otherwise you will be required to think about waterproofing a whole system and loose the plug and play ability to change packs.
Lipo batteries - why is that nobody uses it for foil-assist builds?
I can suggest a few disadvantages when comparing to 21700 dyi:
- extra weight
- extra price
- shady manufacturers
- they can puff
On the plus side:
- x2-x6 lower internal resistance
- ready to use
Buy it, place into a box with Receiver, Bec ,ESC and y-splitter - done. What is not attractive here?
Lipo has a very short lifespan. And at one point, under normal conditions of use, your battery may swell and, if you are unlucky, catch fire.
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energy density for LIPO is low compared to other cells, so you get less runtime but relatively high peak power
take 2 of these https://hobbyking.com/en_us/turnigy-nano-tech-3300mah-6s-45c-lipo-pack-w-xt90.html for 12s 3.3AH, weight 555x2=1.11kg
energy density is:12x3,6x3,3/1,11=128wh/kg
compare with molicel p42A 12s2p 8.4Ah, weight 1.632kg
energy density is 12x3.6x4x2x2/(12x2x0,068)=222wh/kg
that’s 74% more energy per weight. some added nickel connections would lower that a bit but still a huge difference.
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follow my post, I am just built one, yet to be out in the water, but very soon it will be
is this boc just a model for alu box? or do you plan to use it? will it be strong enough
That was just a quick mock-up to see what it looked like. There’s too much compression on a FDM 3D print in the bolt areas to really use it. I have access to big enough CNC’s to be able to cut from aluminium.
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how is the resistor (10 ohm/5 watt) used as anti spark?
Always in serial?
Here are some ideas for a DIY Foil Drive Assist:
https://foil.zone/t/new-diy-foil-drive-assist-killer-from-austria/20388/
yep, like an 5W resistor 100-1 ohms you prefer how much sparking current you’d like, 10 ohms may be good upto 100V systems i think.
You first connect the ground electrode, then the positive electrode through the resistor, wait until the capacitors charge (few sec) then plug the positive.
That amazing cable guide for the axis alu mast - would you mind sharing the model file you used?
Looks like low drag and good fit. Great build!
Thanks mate, the cable guide is created by @pablo_foil
It fits the three 12AWG wires perfectly.
Shape of the Gong V1 mast is slightly different to Axis mast, but couldn’t bother to change the file for perfect fit.
Here’s a link to pablos thread:
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Hi all,
This forum has been really helpful for me and my first DIY build so thought i would share what i have come up with as a solution for ESC cooling. I am using the same Flycolor X-Cross HV3 160A as above.
Even with an external heatsink mounted, i was finding the controller gets up to my thermal limit pretty quickly. Probably because my external heatsink was only cooling the fets on one side of the ESC. So i decided to remove the small internal heatsink and machine a clamping bracket that should pull heat from the other side to the external heatsink as well. Then i replaced the original small heatsink back on for good measure :P.
Curious if anyone has done something similar and if it has worked? Im yet to test mine.
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Nice motor mount design! I have the same GoFoil mast type. Any chance you want to share the step / stl files for the motor mount? Thank you!
@s9tim How is your antenna laid -which orientation? I have been looking into this myself and come to the conclusion that it should be laid at 90 degrees to the length of the board (ie width-wise) - due to the torus/donut shape of radio signal. I have yet to test.
I have my antenna in the vertical position similar to the foil drive setup. Never have any signal issues unless the box goes underwater.
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I have done this for an APD ESC and it worked fantastically. I am also planning on doing the same for my X-Cross.
Did you use a heat gun to remove the existing heatsink or just brute force?
Hi @Jezza,
Nice. I’m looking forward to testing this.
I didn’t use heat, I just used a scalpel blade to gently cut through any of the heat sink cement I could access from the side, until it was easy enough to pry it off with a plastic trim tool. The small heatsink on the big capacitor side was way easier than the branded alloy cover on the other side. That one required a bit more patience and force 