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Re: Feel Free Lure Kayak

Posted: 29 Oct 2019, 12:46
by erik the viking
Hey John, have a look at this option.
https://www.youtube.com/watch?v=1eWUtk8-9NE
It is by no means the best or only solution, but it is a starting point.......
There are heaps of alternatives, some super grouse some absolute crap.
You just have to remember that it must be waterproof inside the box, and that includes the potentiometer and switch cutouts.
In saying that, plenty of guys fit the stuff that Robin put in the box inside the original head of the Watersnake.........?
Just don't rush it because you know Murphy's law - in unforeseen circumstances it will all go pear shaped. Guaranteed.
So you don't want a circuit fail out from shore.

PS If you don't want to sacrifice a Hobie drivewell plug: https://www.youtube.com/watch?v=bdOAyHYpYtg

Re: Feel Free Lure Kayak

Posted: 29 Oct 2019, 21:22
by bjspinner
Mindi wrote:I am keen to stick a PWM box on my Watersnake T24 but there is something I dont understand.....if you connect it between the battery and the cables going into the head unit of the T24, dont you still have the dump coil technology in the process..? I get it that you get variable speed control, but surely to avoid the dump coil wastage you need to connect it "later" in the process...like directly onto the wires going down the shaft to the motor head. Clearly I am not an electronics person, so I hope the question is understandable. In any case the install looks dead simple but I dont see how the PWM avoids the wastage to heat.
John
There are 3 wires that come out of the motor, to connect to the pwm you use the two larger diameter wires the thinner wire is for the dump coil.
The dump coil still uses full amperage so you use the two main wires to control the motor only.

Re: Feel Free Lure Kayak

Posted: 30 Oct 2019, 12:48
by Mindi
Yay Bruce...I very nearly guessed that, now it all makes sense to a non electronics person.
Many Thanks....this has been a terrific thread, sometimes forums work as they should. Thanks for all the helpful rersponses.

Re: Feel Free Lure Kayak

Posted: 30 Oct 2019, 17:04
by Mindi
Erik...I have decided to go with the "project box" replacing the head....not that beautiful but I can make it waterproof and I think a very practical solution. I am not yet quite clear on what point there is in retaining the old switches function....if i have a potentiometer knob with an "off " position then surely everything else is just an unnecessary water ingress opportunity...?..or I am missing something

Re: Feel Free Lure Kayak

Posted: 09 Nov 2019, 09:04
by Mindi
Thanks to all the helpful advice here I installed the PWM controller and am now running some wet bench tests to see how much battery is used on a few % settings. Really went well, no problems with the install at all. You can get a box with a clear top which is waterproof and just klarger than the original top half of the motor head.
Seems like a successful project at this stage which is good considering my zero capability at electronics...just 4 power connections to m ake.

Re: Feel Free Lure Kayak

Posted: 09 Nov 2019, 09:30
by erik the viking
Well there you go John, easy peezy eh?
Looks the goods. Well done.
A box, some cable ties, four wires to connect................ :thumbsup:

PS Is the shaft for the potentiometer through a wp grommet? Is the switch wp?

Re: Feel Free Lure Kayak

Posted: 09 Nov 2019, 16:08
by Mindi
Dont ask those questions....it is a snug fit. I am running some wet bench tests. Unfortunately I have no "before" data so while it informs me a bit about capacity I cant relate it to the standard motor...except to say that it seems to run much more economically. For example running at 15% which I guess would be a slow troll...i have reduced my 36AH Gel Battery from 12.80 to 12.54 in 7 hours continuous running.....got sick of that when it was obviously going to run 12 hrs plus... I am now running at 25% and have taken the recharged battery from 12.80 to 12.38 in 5 hours continuous running...so at 25% I probably have about 7 hours continuous. I dont have a suitable ammeter but this is giving me an indication of much better battery life than I imagined.

It cost me $18 for the electronics and $19 for the clear topped box which bolted straight onto the bottom section of the original motor head unit. Thanks to the guy who posted this approach on Youtube... it is not super elegant but works a treat. I actually had to lengthen the red/black coming up from the motor as they were really a bit short one end when it came to fitting the box. I just cut the blue off and stuffed it back down the shaft out of the way.

My takeaway from this is that they are disgustingly slack making motors with dump coils.... In the depths of China how can a coupole of dump coils and some wiring cost less than a cheap PWM. Beats me.
Anyway Eric thanks all your help.

Re: Feel Free Lure Kayak

Posted: 09 Nov 2019, 17:35
by erik the viking
Hey John:
7hrs + on a 36AH gel cell sounds too good to be true.
Is that with the prop in a big bucket or just dry?
I have heard that it is not wise to run these motors dry as they can easily overheat.
Also without a load on the prop the results would be different to on water.
Anyway, 7 hrs dry with more to go is still a great improvement.
They can churn these things out for $150+. All the ones from Minn kota, Watersnake, Motorguide are
more than double that for the 'electronic' version in the 24 - 28lb versions.
I have followed these types of conversions for many years and it is still cheaper to put your own PWM on for a yak.
Saltwater and offshore boating would be different.
Again, well done and I hope you get some good fish where you are heading. :up:

Re: Feel Free Lure Kayak

Posted: 10 Nov 2019, 11:12
by Mindi
Erik

No it is not dry... it is deep in a large bin of water with the standard prop and I agree the figures are surprising. The other thing I have noticed, but may be wrong about...is that the PWM running at 100% looks/sounds much higher RPM than the "HIGH" setting on the old control system...I just have no way of testing that impression except to say that I would be reluctant to dial it up to 100% in practice.
Off to Mallacoota in a few weeks for some shallow water Flathead chasing and I know that on full charge/high speed I got 4.8 kph out of the box.... that will give me my first real test of what % of the PWM equates to "High"...well roughly anyway.

Re: Feel Free Lure Kayak

Posted: 10 Nov 2019, 11:36
by bjspinner
Mindi wrote:Erik

No it is not dry... it is deep in a large bin of water with the standard prop and I agree the figures are surprising. The other thing I have noticed, but may be wrong about...is that the PWM running at 100% looks/sounds much higher RPM than the "HIGH" setting on the old control system...I just have no way of testing that impression except to say that I would be reluctant to dial it up to 100% in practice.
Off to Mallacoota in a few weeks for some shallow water Flathead chasing and I know that on full charge/high speed I got 4.8 kph out of the box.... that will give me my first real test of what % of the PWM equates to "High"...well roughly anyway.
I run one like this of my battery, that way I can check the capacity once recharged is consistent with the discharge.
Will also give you max amps draw, etc.

https://www.ebay.com.au/itm/Watt-Meter- ... 0005.m1851

Your bucket will be creating a whirlpool effect so the load figures will be inaccurate, also the runtime will be affected by this ( increased ).

Looks good Mindi, the main can in the motor can be twisted also to alter the commutator timing of the electric motor.
Take of the prop and loosen the two screws so the centre can can be twisted, while running the motor you twist the centre ring and the motor rpm will increase or decrease best to get the same load in both forward and reverse.
Increasing the rpm also increases the amps used and heat levels but puts out more power(watts) in one direction only as when you twist the centre it changes the magnet position to the brushes contact point of the commutator.