Thanks for sharing these.
Can anyone point me to how to assemble… not exactly sure where threaded inserts are used vs nuts. Also does the folding prop use some kind of bushing and/or what pins?
Also wondering if anyone has moded the CAD files to allow a SS or alloy strap as a safety measure incase the printed plastic fails- eg a aluminum or SS base plate inside the rear mast mount and a front strap inside the nose cone that the threaded rods go through (around the front of the mast in side the cone with 90 tabs that the threaded rods pass through)?
Anyone experience with this MICHOBBY folding prop regarding performance and durability?
only compatible with maytech motor, too large in diameter, mine lasted 2 sessions before the blades broke. The hub itself is quite strong and I still use it.
Mine came with M3 bolts that I replaced with M4 as it was designed for this size.
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Thanks. Thats all the info I need to steer away from this prop. I might as well go for a 3D printed if Ali nylon prop breaks that easy
Do you have any ideas for a locking solution for the 3d printed cover of this box?
There’s only a 2mm clearance inside for battery replacement, with minimal protrusion outside preferred since it will eventually be submerged underwater.
I’m considering something as simple as using a strap along the length of the box to secure both covers in place, while silicon insert will be used for waterproofing.
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@Jezza Love this design - how did you get on with this?
Are you planning on using 3D print (is this strong enough?) for final or mill/CNC aluminium?
Have you shared your plans? I am keen to do similar. I was thinking 3D print shell with some aluminium bar inserts to take load between foil plate and board (with holes for screws to pass through).
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How is the FDGen2 waterproofness ensured at clamp level between nose (or tail) and main body ? What’s the principle behind it ? Close-up pictures welcome.
I’d 3d print a mold and make a thick U-seal using gasket silicone, but TPU printed seal in 95 ish hardneds should also work from what I understand?
Edit: Looking at your alu case opening I’m thinking that it would cut and split the seal if clamped
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Hi I am also interested on how to waterproof Li-ion battery pack. It’s hard to find some info on this. I was thinking a mold of PU foam bi component but how does it perform with heat ?
Options I know include mg chemicals thermal epoxy, natural cure silicone (marine type - not vinegar/acid), potting silicone, normal epoxy, glue + vacuum bag (kitchen souse vide type, seal over outgoing silicone cables),…
All options should resist 150C+ afik but resulting weight and application complexity varies. Durability…? Thin epoxy is heavier and less risk of air pockets, thick silicone harder to get tight?. Vacuum can perhaps be used when potting with silicone?
Battery design should ensure limited heating to avoid puffing. Potting at right room humid/temp cant hurt either.
Thanks for the detailed options on heat-resistant materials and application insights - will help me to get deeper on this.
I intended to pot with electronics silicone the ends of the cells including nickel.
But now I intend to only double heat shrink the whole battery + put glue between the heatshrink and isolating paper at the end. Watch my build.
The special feature of electronics potting silicon is thermal conductivity.
This thread is such a great resource! The countless hours on this forum gave me the confidence to start my own build even if I have no previous experience in such projects. I have started ordering parts for my build over the past few weeks, including 24 Molicel P45B batteries that I plan to use in a 12s2p configuration.
However, this will result in a 26 cm long batterie pack, which I find a bit awkward to fit in an assist case. Could anyone tell me if there is a straight forward way to physically arrange the cells in a 8s3p configuration, but to weld them so they are in 12s2p? I think I have a rough idea, but having one of you help me with this would be very helpful.
Also, I have used @ludwig_bre Battery Pack Nickel Strip Calculator to help me decide on which material to use for my pack, but I am not 100% sure how to interpret the results. Would using the steel strips with nickel plating sufficient? I cannot find the pure nickel strips at a reasonable price, but don’t want to create a bottleneck or a dangerous situation to save a few bucks either.
8/3 you can connect like this
Make sure to pay extra attention to the areas with red dots, they will see a lot of current, so make them at least double what the rest is
Regarding result of the calculator: The strips heat up to more than 250°C above ambient, that is way to hot! You need more (thicker) material for the strips for sure
Also be aware the cells you chose are only allowed to be discharged with 45A if you monitor the temperature and keep it below 80°C
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Thank you! I will go for pure nickel then, and also double the thickness of all my connection. The calculation indicates that this should result in a strip ΔT of 30 C, much more reasonable.
I used the maximum rating of the cells for the calculation, but I hope I will be able to use a lower maximum discharge current. Very good point about the temperature and the need to monitor it, I will keep that in mind.
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Stainless steel 3d printed folding prop
RAW
After 1h of sanding and dremel polishing
I paid around 30€ each at: Online 3D Printing Service | Custom 3D Printed Parts - JLC3DP
This is an affiliated link, we both get some extra discounts
Those they should brake 
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Expensive 3D printing, heavy stainless steel, post-processing required. What are the advantages over milled aluminum?
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I like that 3 blade foldy. Is there a file you can share? How much did it cost to have that done?
Unfortunately, I can’t, this is not my photo. And I don’t like this propeller because the Chinese found the blade model on the Internet and started installing it without thinking. This is what their base looks like). I published the photo only as an example.
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They look very nice and clean, I was sending my files for cnc, but was more expensive then made them from steel, so I did that