I want to build a simple and low cost winch to drag a foil board (small surf board).
Purpose is to learn/do foiling/pumping.
My plane is to use an regular electric bicycle with a hub motor - just instead of the rear wheel use only the motor. The dynema wires will wrap around the motor+something-around-it.
As a start - no remote - with bicycle operator.
The common bicycles motors here in Israel are 250W-500W and with additional cost it can be replaced with 1000W. Cost $500-$1000 including battery.
Alternatives:
Rewinch - with taxes and shipment it will cost around $4500 without battery
FoilDrive - around same price $4500
What do you think about this plane?
How would you improve it? These hub motors - how strong should be the motor?
If these motors are too weak, I can set higher requirement on the foil board volume - it can be even 160L…
I bought a rewinch mechanical only kit (I emailed them about it) and then did my own electronics. It’s came in far cheaper, but from a kit perspective it’s not the most ideal. There are a lot of improvements it could have. At one stage I actually planned on designing my own electric winch but I just don’t have the time at the moment.
I also made my own foil assist which I far prefer to using the winch. It give you more freedom. It also allows you to start anywhere.
There are other systems like bungees and board holder that help with pumping. Check out wakethief on YouTube of you haven’t already.
Right!
But when doing a build, it is so much more than money. The whole time investment on research, shipping logistics of parts and implementation…
This is why if doing a build, I will do foil-assist.
The bicycle is already accessible, the simplest it can be.
But maybe there is a simple tow buggie build, what would you recommend?
Ye , I plan to build a foil-assist , but first want to get wet
Next step is winch and yes dock-start. My thinking is that winch will help me with the dock start…
In all honesty, a winch is a bit of a hack and pain to use unless you have friends with you or you design a closed loop setup. It’s a pain to have to go back and forth to pick up the handle.
The PVC dock launchers are fat nicer and simpler. Take a bit of a run up and just jump on…
The other best alternative is the tow boogie…
Ok, I agree, you have the experience.
But when dock start by running, is the jump accurate regarding feet placement. From reading I got the impression that better is to place hands first. This is why I plane ladder start.
I had the same plan of practicing with a winch, and then going foil assist / wing / prone with those skills. I’m almost done with the winch now, and it was much more of a project than I think just going to foil assist would have been. Just feels like more moving parts and more things that can break. For reference, I built around a 6384 motor with a 12s setup. It can easily lift 16kg worth of water bottles at high speed (that’s all I had laying around - though the theoretical max should be 40kg) and should have a top speed of 25 km/h based on the RPM and spool size. Total cost so far including batteries is around 600usd. If I had to do it again, I would go right to foil assist. That said, my friends and I can now practice together - we are all relative n00bs.
I will post a build when I have time, but the the key specs are 6384 140kv motor, 12s lipo battery, 6:1 gear ratio, 14cm diameter spool. I built it in an ammo box with another one housing the battery.
@foilinghopeful Great build. I’m inspired to follow a similar path. I wanted to ask you about your experience in rope spooling without any manual alignment. If you spool the entire rope length without hand aligning the position of the rope, would it distribute evenly, or will it clump up on one side, specially if there’s force pushing it in one direction. I was thinking about adding a ball screw mechanism to align the rope back and forth as it spools, but would rather skip if not necessary. So just curious about your experience in that aspect.
I think you’ll be fine keeping it simple. In my case, it isn’t perfectly even, but it mostly spools fine. When my winch is strapped down, it has a little bit of rotational wiggle room (it sits on concrete with a plastic tray under it to reduce friction). As a result, if it is pulling with any significant force, it mostly points directly in the direction of that force thus keeping the spooling distribution relatively normal. If you fix your winch facing a certain direction and veer off to the side (I’ve done this with the winch in sand), or if there isn’t much resistance to pull the winch in the direction of the force (like spooling the rope in at the end of a session with just the drag from the handle in the water - only happens if nobody took the last ride), then it can build up on one side. But, that doesn’t appear to matter. Unspooling works fine, and that 2mm line takes very little space. I hope that helps.
This definitely helps and will surely simplify things, at least initially. I’d like to know your experience with the 6384 motor. Did it provide sufficient power? I see it’s rated at 3.5KW but the torque seems more on the low end (8Nm). Not sure why rewinch advertises 12KW if something much lower power works well. So just wanted your thoughts on whether something like the 6384 did the job, or you’d go for something bigger in your next build
In short, you’ll have plenty of power unless you are trying to deep water start and weigh around 80kg. But, even then it might work with a better gear ratio to increase torque. It really feels like it can rip off your arms if you don’t add some ramping. Someone else was asking about power in a private message. I added that info to my build thread.
@foilinghopeful Many thanks, this is all very helpful. Seems like the motor gives enough power to meet the need. I’ve been looking at some of the QS Motor units, but seems to be an over kill. And the price point is much higher as well. Thanks for all your great insights.
Hi, I have used a UNU Hubmotor 3kW. It has more than enough power.
You can also use the 2kW for foiling - more than enough.
Used the 2kW Motor costs aboout 80-100€
The advantage is, that you already have the spool with the motor.
I removed the rim bed and screwed a V2A plate on it. See the pictures:
