`

Author Topic: Personal tow in  (Read 5548 times)

PonoBill

  • Cortez Bank Status
  • *****
  • Posts: 24428
    • View Profile
Re: Personal tow in
« Reply #30 on: December 19, 2020, 06:23:12 PM »
You still have to lug it to the water. I used mine today in Mission Bay. Very fun. But how long do I really want to be towed around on my foil.

I went out first in eFoil mode. Cruised around, went looking for boat wakes to cross (lots of them), did a big lap around whatever they call the bay section with all the sailboats and a few kitefoilers. there were even a few wingdingers out, and I watched them carefully to see if any of them were getting up on foil (nope). Got bored with that, came in and attached my tow rig, took the wing off the Takuma and went for it. Easy money. I towed around for about as long as I wanted to without waves to chase, came back in and still had half my battery. Once you're up on foil this thing sips power. Total time in the water was about 2.5 hours. I really need to have the "come back and get me" feature and go out in the open ocean.

I added a collapsable paddle to the deck that straps on to the PVC guide pipe for the towline. My thought was if you don't pay attention to the charge readout and run out of power you could get back without a permanent crick in your next from trying to prone paddle this thing. I still think it's a good idea, but for breakdowns, not battery life. I haven't run this thing out of power yet.

My tow attachment is pretty cool. I'll have to do a video on it. I could leave it on the board permanently. I found these slick stainless u-bolt thingies at West Marine that have a rubber base. 29 bucks each, but they hold the PVC pipe so soundly I could use them as the only anchor point. Of course, I won't, the tow rope goes through the pipe and ties to the handles on each side of the board with a simple harness, but they're very good.
Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

Piros

  • Sunset Status
  • ****
  • Posts: 452
    • View Profile
    • www.vonpiros.com
    • Email
Re: Personal tow in
« Reply #31 on: January 03, 2021, 07:48:30 PM »
Hey Bill still keen to see your setup if you had a chance to do a video or pics.
Von Piros Productions
Land Behind, Fish Below, Stories Ahead

juandesooka

  • Malibu Status
  • **
  • Posts: 55
    • View Profile
    • Email
Re: Personal tow in
« Reply #32 on: January 07, 2021, 04:04:44 PM »
Awesome, love the ingenuity.

I got intrigued (maybe suckered) by a kickstarter: https://boostsurfing.com/
I can't imagine surfing with it will be much fun, too much drag in the water.  But if attached to a foil mast base, maybe just enough juice to get you up on foil, then from there the motor is up and out of the water.  So....maybe another version of a personal tow in? 

I expect to be disappointed, keeping my hopes really low.  But the dream is getting in super early on swells that are otherwise not paddleable.


PonoBill

  • Cortez Bank Status
  • *****
  • Posts: 24428
    • View Profile
Re: Personal tow in
« Reply #33 on: January 07, 2021, 06:33:05 PM »
Hey Bill still keen to see your setup if you had a chance to do a video or pics.

I'll do that next time I have it out.
Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

PonoBill

  • Cortez Bank Status
  • *****
  • Posts: 24428
    • View Profile
Re: Personal tow in
« Reply #34 on: January 07, 2021, 08:15:49 PM »

So they ask "The future yes or no? 😲" I can imagine these tow-drones could also become a little mother ship. It could store drinks, food, first aid (oxygen!) and have a little waterproof garage to launch, retrieve and recharge a flying drone. A second camera station. Another garage for a nano-submersible camera drone.

Oh crap. That's actually feasible--the flying drone port part.
Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

PonoBill

  • Cortez Bank Status
  • *****
  • Posts: 24428
    • View Profile
Re: Personal tow in
« Reply #35 on: January 12, 2021, 03:37:00 PM »
Fiasco!! My new flag/rope extension screwed up everything. Not only does it not turn better, it also picks the nose up easier, which is completely the opposite of what I expected. In my usual stupidly optimistic way I switched from my 1150/440 combo to a 860/340 that needs a lot more speed. It seems that I was getting away with a lot of mediocre choices by simply going slower which the 1150 permits.

Once the nose comes up enough it starts torque steering and wants to go left. the longer extension out the back somehow makes the steering substantially worse and does nothing to combat the nose lifting. I'm starting to understand why (I forget the guy's name) that turned the foil around backward did so. I also understand why he connects the tow to the mast. I was getting away with towing from the deck because A. I was going slow. And B. I have a short mast (40cm) to begin with. Even with the extension shoved as far forward as it would go the steering was much harder and required slower speeds to work. Like kneeling on the board, not foiling slower speeds.

Oh well, back to the drawing board. A learning experience, yeah that's what it was... A learning experience. I put the foil back on the Takuma, did a consolation lap around the bay, and went home to drown my sorrows in Spaghetti and kale-stuffed meatballs (way, way better than it sounds) and a nice glass of Bastide Miraflores.
Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

toejammer2

  • Malibu Status
  • **
  • Posts: 85
    • View Profile
Re: Personal tow in
« Reply #36 on: January 17, 2021, 03:57:57 PM »
Hello PonoBill,
I posted on your Foilzone thread. My eyes are bugging out after searching all day for a couple of 6s 22ah lipo batteries. Do you have a  favorite site where you buy such things? Iím also trying to figure out the potted motor mount. I bought a 3d printer but have no idea what Iím doing!

Cheers!

PonoBill

  • Cortez Bank Status
  • *****
  • Posts: 24428
    • View Profile
Re: Personal tow in
« Reply #37 on: January 17, 2021, 07:03:38 PM »
I mostly build my own battery packs, but when I buy one it's generally from Luna Cycles. they do a really good job with batteries individually fused and a good BMS. But their lowest voltage pack is 48V.

You can learn to build battery packs online, but if you do, make your first few packs with LiPO4 chemistry--less likely to burn up.

Why on earth are you looking for 6S? That sounds like you want 24V, but 7S is much more common for 24 volts from LiPo. Nominal voltage for a LiPo battery is generally stated as 3.6V to 3.8V. Maximum voltage is 4.2V, low voltage will be 2.5V ~ 3V. A 7s pack will be 29.4 V at full charge, 21 V at low voltage, 25.9 nominal.

MaxAmps is a reliable company, they've been around a long time. Here's a 7S 22A pack: https://www.maxamps.com/products/7s-lipo-battery-25-9v. You will need a GOOD charger and if it's a variable charger you need to know EXACTLY how to program it. There's no room for error with any of this stuff. Safe if they're operated correctly, not at all if they are not.

With batteries I build, I never charge LiPos to more than 4.15 V and never discharge them below 3.2V. that's leaving a lot of power on the table, but it's safer, and easier on the batteries. When I use commercial battery packs with supplied charger I check the cutoff voltage after giving them a full charge. some of these folks skate close to the edge. My current bicycle battery cuts off at 4.2 V. LiPos can be damaged at 4.25V and sometimes that means they go into thermal runaway, a nice way of saying they catch fire and burn, and a VERY hard to put out.

I charge my bicycle on the street outside the house.

If I were going to build a tow from scratch it would be with a single module from a Tesla Model S. You can get them for about $1000-2000 or thereabout--7s, 200ah and welcome to the big time. But then you need a battery controller that can connect to the Tesla slave BMS boards and heavy-duty contactors to cut the battery off if it approaches over- or under-voltage. And then you need to make it absolutely waterproof--no room for errors. Fuck it up and all that energy needs to go somewhere.

Not to just scare you off, but do your research carefully, and when you start messing around with these things do them someplace fireproof. I do my battery projects in a steel container placed about 100 yards from my shop. Lots of people have burned their house down screwing with this stuff.

If you haven't fiddled with these batteries before you should get a well-engineered charger and battery combination.
« Last Edit: January 17, 2021, 07:13:58 PM by PonoBill »
Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

toejammer2

  • Malibu Status
  • **
  • Posts: 85
    • View Profile
Re: Personal tow in
« Reply #38 on: January 17, 2021, 09:43:48 PM »
Good info! Thanks!

 


SimplePortal 2.3.7 © 2008-2021, SimplePortal