Tested the electrics/propulsion system and it’s all systems go with the components, so now comes the assembly.
For those not following in the chinese foil thread, the alibaba foil finally arrived. From the appearance and components I guessed it was a slingshot hover glide NF2. It only came with a 65cm mast, so I went to the local retailer to grab a 95cm slingshot mast, guess what it’s exactly the same.
I also purchased a board from the local retailer, who funnily enough knew exactly what I needed, as one of the guys from fliteboard had been in that morning and been foiling out the front of his shop. Small world.
I’m also using @cwazy1 redesigned prop. It uses a 8mm/8mm coupler on the shaft to hold the prop onto the shaft. Easier for me then drilling/tapping the HSS 8mm rods. I’ve also gone with @MaxMaker’s suggestion and using a flexible coupler from the gearbox to the driveshaft.
Yeah, same. However subsequently he’s written on the forums that there was some water ingress, with suspicion that it was due to concentric movement from the shaft against the lip seals. Whilst the addition of the ceramic bearing can help stabilise, I think the flexible coupler will also help this.
I didn’t use a flexible coupler. If you plan on using a flexible coupler I would update the design to add additional bearings to stabilize the shaft, more than that one ceramic bearing I added recently. If the shaft wobbles the lip seals fail.
The use of a prop balancer to balance the prop before use could also help eliminate any shaft vibration. I recently purchased one from Hobby king for about $40.
Frsutratingly slow progress, due to multiple fucks up (and therefore backtracking to remedy a design/assembly steps), waiting for parts and time.
However hit a milestone today! Only 6s and I need to mod the M4 screws, but it works.
Spent a lot of time reading about the board modification process. I think for Mk2 I’ll find someone local to build a custom board from scratch, but I think I’m ready to mod my current board, fingers crossed I’ll get time to do it this week.
Thanks again for everyones advice and hints in this forum. Certainly wouldn’t have even made it half as far without the resources here.
Lots of fuck ups, probably mostly avoided by doing more reading and planning ahead. Printing and assembling things with 20% infill instead of 100%, printing things the wrong way round, forgetting to loctite things and having to reassemble! Live and learn!
In terms of the bullet connectors at the motor, they’re connected via 5.5mm connectors, which are heatshrunk and then wrapped in tape. These are enclosed in a (hopefully) waterproof section of the engine pod, with lots of silicone at the proximal mast end (both sides) to seal out water ingress.
So 2 steps forward and one step back - slow progress.
Finished the pod, assembled it, put it on the mast to test in the bath after letting everything cure and bang. Killed the electrics with the test. When threading the wire through the mast, a small metal shard from the internal aluminium section has nicked a large non visible section of 2 of the three motor wires, causing a short when water got in for the test. Making mistake is all part of the process, so start again!
So with everything purchased, checked and assembled again; it’s time to test again!
All ok on 6s, let’s try 12S
Success. Obviously lots of cavitation with the water depth, but it’s good enough for me to finish preparing the control electrics box and start mounting it all on the board. I’ve manually routed out a small section between the mounting tracks and epoxy resined it to run the wires out.
I’m really wanting to make a larger thicker board to mount everything internally, but having a hard time finding someone local. If anyone has any Australia board builders who would be willing to have a crack, let me know.
Awesome! Great to hear that it’s coming together. I love your bathtub test, especially with 12S. Quite the whirlpool. Thanks for sharing your progress, we are looking forward to the next updates. Good luck!
The shaft just slid out due the momentum of the forward motion, with the drag of the water on the prop pulling it backwards through the seals and bearings. I got some lift, but it was about 50% throttle as it was a bit of a shakedown, so I wouldn’t say I got up.
Live and learn. All part of the fun.
In other news I’ve found a local guy who is gonna build a custom high volume board for this project. He’s familiar with the fliteboard guys, so it was good to have a sit down with someone who knew what we needed.
If there’s any other aussies interested in a custom board, let me know.
