Electric drive "ED"

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Utility
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Location: Toledo,Ohio

Electric drive "ED"

Post by Utility » Wed Aug 01, 2018 9:55 am

Has anyone used the "ED" drive featured in the plans section? I am thinking about trying it on glen l utility. I am wondering if handling and performance would be about the same as an inboard and rudder arrangement. Any thoughts?

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sproggy
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Re: Electric drive "ED"

Post by sproggy » Thu Aug 02, 2018 6:36 am

Steering would be more similar to an outboard than to an inboard because you steer by turning the outboard lower leg, directing the thrust where you want it. So you'd have good manoeuvrability at low speed which you don't get with an inboard and separate rudder. On the downside, low speed is the only speed you'll have available to you and the Utility hull will be much less efficient at those low speeds than a displacement hull.

If you want to go with this power system I'd suggest looking at the Amp Eater - it's designed to be efficient at the sort of speeds this arrangement will allow you to travel at. If you want a higher speed (planing) hull with electric power the ED arrangement isn't the right approach IMO. There's a limit to how much power (torque, actually) that you can transmit with v-belts.

Utility
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Re: Electric drive "ED"

Post by Utility » Thu Aug 02, 2018 7:08 am

I was thinking of going with a modified version of the "ED". I was thinking a 5kw golden motor on a coupling to the outboard shaft. It should give me about the same output as an 8hp outboard Glen-L recommends. I know I can't adjust the by angling the outboard. I might be able to add trim tabs if needed the transom. I was curious if moving the prop forwards would do to the handling at low and high speed vs an outboard.

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sproggy
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Re: Electric drive "ED"

Post by sproggy » Thu Aug 02, 2018 7:22 am

Ah, if you're getting rid of the belts then that opens up more power options. Watch the gearing, though. The ED design allows you to effectively gear the motor to the outboard leg via different sized pulleys. If you're going for a direct drive via a coupling you won't have that capability. Electric motors run at lower speeds than gas motors and you have reduction gearing in the outboard gearbox (lower leg) that'll bring the speed down further. So you'll end up spinning the prop way slower than is ideal. I'd guess outside of the scope of what you could cater for by changing prop pitch/diameter.

You might want to consider keeping the ED layout and replacing the V-belts with either a toothed belt (Harley style) or a chain. Either of these options would give you step-up capability to increase the input speed to the outboard leg. But you'd have to beef up the design to cope with belt tension.

Moving the prop inboard by a foot won't significantly affect the boat's performance but the Utility is designed to have an outboard mounted on the transom so you should replicate the design weight distribution as closely as possible - keep at least some of the batteries well aft.

Utility
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Location: Toledo,Ohio

Re: Electric drive "ED"

Post by Utility » Fri Aug 03, 2018 9:14 am

Good idea about the cog belt. That would even lower side loading vs V belts. I was thinking the same thing about motor top speed vs a two cycle outboard. Thanks for the idea.

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aero_dan
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Re: Electric drive "ED"

Post by aero_dan » Wed Jan 23, 2019 11:54 am

I have 2 comments, 1, motor speeds, and lower unit gearing.

The type of motor used can greatly effect the end speed of the drive. I know of motors than run at just a few hundred RPM, and others that run at over 13,000 RPM. There are shunt-wound motors, BLDC motors, AC "phased" motors, etc.
Contacting folks like Golden can be a bit frustrating due to language, but they actually build their motors for the marine applications and desired RPMs. Also contact folks like D&D in New York. There are winding designs for about every application. Places like White Cloud and Thunderstruck can be of some help too. They are just a couple of the popular companies that offer parts and systems. And the folks at Annapolis Marine and Electroprop Propulsion are great sources of information and associated systems. I have consulted with all of them successfully.

Now to address the lower unit options. Many of the outboard manufacturers make different lowers based on applications. If the O/B is to be a trolling motor, the gearing in the lower is different than for a speed application. In my case, I chose a higher ratio of 2.33:1. This was a good (computed) ratio for my motor that tops out at around 5,400 RPM and is just under the ICE counterpart of 6,000. Do the due-diligence and look at the ratios of your available lowers to match up to desired motor. There is nothing wrong with direct drive if you can find the right lower unit gearing. I suspect that in the future, a company will emerge that offers better gearing specifically for various motors.

Bottom line is, the ED system is a good DIY approach to propelling your project. However it is incumbent on you, to find the best ratio for your build. Hope this helps.
Better, faster, cheaper. Only ever found 2 of the 3! (But still lookin.)
So many boats, ...so little time.

Chopra
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Re: Electric drive "ED"

Post by Chopra » Wed Feb 06, 2019 1:22 am

on the off chance that you're disposing of the belts, that opens up more power alternatives. Watch the equipping, however. The ED configuration enables you to viably adapt the engine to the detachable leg by means of variously measured pulleys. In case you're going for an immediate drive through a coupling you won't have that capacity. Electric engines keep running at lower speeds than gas engines and you have decrease equipping in the detachable gearbox (bring down the leg) that'll cut the speed down further. So you'll finish up turning the prop path slower than is perfect. I'd surmise outside of the extent of what you could provide food for by changing prop pitch/distance across.

You should need to think about keeping the ED format and supplanting the V-belts with either a toothed belt (Harley style) or a chain. Both of these alternatives would surrender you step capacity to expand the information speed to the detachable leg. In any case, you'd need to reinforce the plan to adapt to belt pressure.

Moving the prop inboard by a foot won't altogether influence the vessel's execution however the Utility is intended to have a detachably mounted on the transom so you ought to repeat the plan weight circulation as intently as could be expected under the circumstances - keep probably a portion of the batteries well toward the back.

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