Electric Boating

[bobkart]

Bare Boat. The GoldenMotor EZ-S10 on the eCAT seems decent (and is still an option for me), but I have my own batteries and can source them less expensively than theirs.

A similar option to the EZ-S10 is the ePropulsion Navy 6.0 Evo. Slightly less power but looks to be more efficient. I got a demo of an earlier version last year (before 'Evo').

https://www.epropulsion.com/navy/

 

[bobkart]

Getting some interference on the trailer hitch installation . . . have emailed pictures to eTrailer, and their technician is supposed to call me today.

 

[bobkart]

Order placed for ePropulsion Navy 6.0 Evo:

https://www.epropulsion.com/navy/

I should see about 14mph top speed. With the 10kWh battery I have, should get 1.5 hours at that speed, with 10% battery capacity to spare. So 21 miles of range.

At half power, I should see close to 10mph. So three hours of runtime and 30 miles of range.

 

[bobkart]

Got a smaller motor I had laying around installed (2.2kW Hangkai). Came as a tiller model so had to fabricate steering linkage and wire throttle/etc. for remote use.

https://www.dropbox.com/s/586i59m154nuxu9/Electra-full.mp4

Seeing just over 7mph top speed, and would run for 4.5 hours at full power, for a range of over 30 miles.

 

[bobkart]

6kW motor shipped today . . . should arrive either Sunday or Monday.

 

[bobkart]

Any day now on the 6kW motor. In the meantime, we got out onto Lake Sammamish this last weekend.

https://www.youtube.com/watch?v=4aVHY3oM3pY

 

[nlspace]

Be careful when going out for a "3 hour tour"-- yall could end up like the Howells, Mary Ann and Ginger.

 

[LeftieBiker]

It's helpful to be able to fast-forward, or to have the duller sections sped up, but when it's mostly or all FFWD, I expect to hear the theme music from "Benny Hill"...

 

[bobkart]

Be careful when going out for a "3 hour tour"-- yall could end up like the Howells, Mary Ann and Ginger.

My other half already calls us 'The Professor and Mary Ann' (her name is Mary).

 

[bobkart]

It's helpful to be able to fast-forward, or to have the duller sections sped up, but when it's mostly or all FFWD, I expect to hear the theme music from "Benny Hill"...

Yeah I'm definitely pushing the limit of how long of a video I can squeeze into a tolerable duration.

 

[bobkart]

The 6kW motor arrived last week, and we got out on the water with it today.

It worked well; good power and speed. But we experienced ventilation (also referred to as cavitation) approaching top speed.

Transom could be a bit lower. Also, ePropulsion makes an 'anticavitation plate', so that's another option.

On one run I saw over 20km/h, so around 13mph. Assuming that holds after fixing the ventilation problem, that's right in line with my estimates.

 

[nlspace]

i enjoyed the lap of the lake video and thought it was a great presentation at the ffwd speed to show the size of the lake--be glad you don't have to row that in a canoe.

i always thought of "ventilation" as something that a shotgun blast of birdshot would do to your face when out hunting with dick chaney,,, :lol:

 

[bobkart]

Thanks for the feedback on that video!

Yeah I keep trying to use the proper term for what I'm seeing, despite generations of it erroneously being called 'cavitation' (including by me).

https://www.youtube.com/watch?v=5bj5kjh3l9o

 

[LeftieBiker]

To put it another way, cavitation occurs completely underwater, with all of the air involved coming from the water itself "boiling," as it's put above. A submarine a mile down can experience cavitation. Ventilation involves air from the surface getting pulled down into the prop(s), so it pretty much always happens when the propeller(s) is too close to the surface for the speed at which it's turning and the shape of the prop itself.

 

[bobkart]

Yep. I'll probably pick up a bolt-on plate to help prevent air getting down to the prop, and try dropping the transom down an inch or so.

Then experimentation should help me decide whether I need both of those, or if just one will suffice. Both changes are reversible.

 

[bobkart]

We got out on the water a few days ago with the transom lowered one inch. At first it would still ventilate at top speed, then I trimmed the motor in five degrees and that pretty much cured it.

It was windy and rough, as can be seen in this rear-facing video:

https://www.dropbox.com/s/kmsuo94jgmygkeq/GP010001.mkv

I saw 20.x km/h on the readout, so about 12.x mph.

Here is a photo that shows the trim angle:

It would still ventilate in the worst of the waves. I'm pretty sure the so-called Anticavitation Plate would cure the problem the rest of the way, and probably allow me to go back to a straight-ahead trim angle, and maybe even allow raising the motor back up to the original height.

 

[nlspace]

Gosh that is really quiet, and its quick too. Sometime you should show a picture of the whole boat.

 

[bobkart]

Yeah the new motor is much quieter than the cheap 2.2kW motor I was using before.

Yesterday I test-fitted the Bimini top:

Motor and battery have been removed, along with the cross piece between the two rear braces, where the rear-facing camera mounts.

Here is the Rowing Solutions website:

https://www.rowingsolutions.com/

There are a few videos near the bottom of that page.

Here's a short video I posted a few pages back in this thread, when I had the smaller motor installed:

https://www.dropbox.com/s/586i59m154nuxu9/Electra-full.mp4

 

[bobkart]

From the last outing, when that rear-facing video was recorded.

 

[nlspace]

that's a nice looking boat, and i really like the looks of that motor too.

i don't know about boats, so what would be the effect of the angle and raising or lowering the motor--does it control the torque moment that is lifting the bow?