Isn’t lower frequency better? Search for rc sub radio. There are plenty of bands available below 100mHz.
Extended antenna is also an option but you lose a bit of simplicity
@Larsb interesting looking at the RC subs, maybe there is a path reverse engineering those, or hack the receiver into the pod. as of now, i am leaning towards running an antenna or wire up the mast. keeping it simple.
Also got the electronics today! including a spot welder:) hoping to be building batteries soon!
comparison of the stators of the 6355 motor and 5080 motor.
The 5080 motor looks to be sealed in a decent manner! the 6355 I am not too confident running in saltwater, I got the “battle-hardened” version, but not very impressed.
currently using the 4.2 flipsky mini vesc, it has a heatsink so thats nice:)
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6355 ist small?
I used 6384
Greetings frank
The 5080 or 5085 stator is too well isolated i fear. The cooling of the inner windings is very bad, worse than normal stator with air cooling i guess. At least the rotor end bell has to be opened to get water exchanged. Curious to see how it performs.
Yeah this is a ROV motor. Made to be run in salt water. The stator is potted in black epoxy with an homogeneous and very thin layer on the slots, same goes for the magnets. Actually, if quantity is not a problem, you can even order a 6380 or 63100 motor sealed the same way. The factory will ask for a moq, but feasible ? It is.
Can you link the specs ? I don’t even think this motor is 2kw capable but I’m not sure.
@JetboardCologne the intent is only to be an assist motor. no need to power you all the way up.
It is very cool you are able to use the 6384motor, it must be a very convenient to build!.
I am now leaning towards using a direct drive inrunner to get the length as short as possible. but not sure of what motor to use or how to best make an impeller.
@Sliman_O do not remember the specs but I believe it is only rated for 800w,. the sealing of the stator and magnets looks quite good actually, but I still don’t love the running outrunners wet…
Here is the current battery design. I finally landed on 6S2P 21700 with p42 cells. planing on using 0.3mm x 7mm nickel strips, maybe too thin? It will also not have a BMS it will be charged on a normal balance RC charger. inputs would be appreciated!
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Looks great! I think you will want thicker nickel or to double it. You will be less likely to roast an individual cell in a couple of those 2p groups if you can ensure they don’t encounter slightly different loads due to the nickel resistances since you are pushing them so hard… speaking of which… are you going to stick a thermistor in there somewhere? Might be nice to monitor/log the temps they reach under use - especially those two center cells.
Where do you plan to solder the main power leads? It is hard for me to tell with the exploded diagram.
I am also afraid of the two central cells! Not planning on having any temperature sensor, but maybe I will add a temperature sticker in the center. Hoping temperatures will be below 80 deg.
- and - I will be on the bottom left (+) and top right (-).
I posted that ( with not much success )
This will help you to find ( on dc amp ) the resistance ( final heat , hard for me to understand but you can get , close with watt , mass, joules and time ) , not much problems to fear between cells connections with the length of the nickel strip in fact, much more on bus bar …
As far as heat with cells , for the middle one , may be if there is enough room , a idea would be to wrap it in a metal shell that would finish around the edge of the tube (?) if that s clear …
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I would use more nickel on those two ends where you plan to pull power from a tab that favors a cell. Normally something like this doesn’t matter, but I think it could help in this case.
How are you progressing with the p42a pod drive concept? It looks like a great idea.
I wonder if anyone has modified your remote to fit the electronics from a maytech remote?
Hey, the poddrive is coming along, but unfortunately slow.
Here is some pictures, next version will have a shorter ESC, and I think I should connect the ESC to the casing for better heat transfer.
Hoping to test this drive on a surfboard soon!
I also tested taping it to my axis foil just for reference.
I got parts to build 3 units so if anyone wants to help development I am happy to ship!
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With a shorter ESC this can be mounted halfway inside the mast. Current ESC is a FLIPSKY VESC variant.
As i understand transmitting wierless signals though water is a pain… That is why I have a wired unit. Maybe there is somthing sonar based that can work?
Having batteries and ESC underwater should be beneficial for cooling.
Did Stoke pay you for your design or is Stoke actually your company?
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No, havent seen the stoke Design until now:)
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interestingly its looks very similar to this! just had a look at their page:)
they also have an offset of the motor to allow wires and probably ESC to be positioned parallel with the mast.
their quick connection to the battery is a nice feature. it also appears as if they have a balance charger implemented within the battery to make this work.
curious if the diameter is the same. I found the 21700 cells to make the most sense based on power output and size.
this would have been very cool if you could have omitted the signal cable, and somehow run a signal through sea water:) acoustics? i think there is a diving watch that has some form of acoustic signal transfer.
I’m pretty convinced they copied your version 
Way too many similarities…
Interesting indeed:) I might as well just share all the files I have on this design here for all to use:) I did order this design about 3 years ago but never got the time/motivation to finish it.
i forgot my username on grabcad, but uploaded the files to Thingiverse.
ideally, there would be no wire needed to transmit a signal from the pod to the board. this design uses a wire. Perhaps there is an opportunity to transmit the signal through water using a sonar/vibration signal and a relay mounted on the board? that would be cool!
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