electric Outboard Mod

[Baysailer]

Just a winter tip.
Rarely use a motor on the DS but when you need one you need one and for me a little electric troller (36#) works well. Problem is the shafts are too long and will catch any line in its area so I shortened it about 8" and it works much better and stows easier too. I followed these instructions: http://www.ecanoe.org/how_to_shorten_yo ... shaft_.htm.
For the battery I use a car boost starter. Small, lightweight, has a handle and so far hasn't died just when I needed it most.

Fred B

[dannyb9]

thanks for the amazingly timely article. i bought the same motorguide 55 motor a few days before the article appeared sweet!

[GreenLake]

... so far hasn't died just when I needed it most.

I almost never take a single battery any more. I've learned you can't predict when they give out.

[jdoorly]

To quote an old quote:

" I learned the first rule of batteries is to recharge them immediately after use, sitting there uncharged reduces their life. The second rule is to use a smart charger. The third rule is try not to let the battery's output voltage get below 12 volts, this also reduces battery life. I think everybody already knows to use a 'deep cycle' battery."

The 5th rule was debated earlier and was probably false so I don't quote it here.

Definitly like having 2 batteries and a selector switch. Makes it easy to switch when one goes low or switch to "Both" when both are low! The voltage and amp meters always let me know the status of the batteries so I can switch over when the battery in use gets down to 12.0 volts (the batteries usually start out at 13.5 volts).

I'm hoping to move my control panel to the port rear cuddy bulkhead so I can see and operate it from the cockpit.

[Alan]

I'd be interested in hearing from those of you with two batteries whether there's any noticeable effect on handling or stability. I've been thinking about making battery wells just forward of the cuddy bulkhead on a DSII and putting two 12-volt batteries, 62.5 pounds each, in that location.

If memory serves, jdoorly and Breakin Wind (and maybe Talbot) have battery wells forward of the cuddy bulkhead, and GreenLake has a battery forward of each bench on his DSI.

And yeah, I'm the guy with the Torqeedo, but supposedly you can charge a Torqeedo battery while it's in use by using its AC charger and an inverter. And since I already have a pair of 12-volt AGM batteries that I bought for my trolling motor, I figured it's worth a try.

[talbot]

Yes, I have a battery well between the cuddy and the mast.
I cut the hole in the deck lengthwise to bring the weight as low and centered as possible. That results in cutting through a main floor support stringer. I suggest placing the batteries crosswise so you can fit them between the stringer and the CB trunk.

My single 12-volt rests on a fiberglass platform in the bilge. The bilge itself is reinforced with 3 layers of fiberglass mat from mast to CB trunk. All this to support the concentrated weight of the battery. The battery sits in a waterproof bucket that rests on the platform and is also supported by a lip screwed to the deck. The bucket is made from two West Marine battery boxes capsuled together (one box was too short). I use the standard battery box top. The battery compartment would remain dry with up to maybe 2" of water in the cuddy. The battery is stabilized in its box with chunks of foam (computer packaging) on sides and top. My hope is that even in a full (turtled) capsize, the battery will stay strapped in its box.

Big issue for me was voltage loss. The run and return to the motor is >30'. I used #6 cable through a circuit breaker on the mast and on inside the combings back to a receptacle on the port seat back. I get about 90' of use out of the 30# motor on full power.

The cuddy-floor mount is convenient to running lights, compass light, and solar input socket on the bulkhead. We often sail at night in the summer, and it's nice having fixed lights and illuminated compass.

[Alan]

Thanks, Talbot. That's a lot of useful information to ponder.

The idea of stacking two battery boxes to get enough height is elegantly simple, and I never would have thought of it. It's really good to know what sort of bilge reinforcement works - I'd been making the sort of plans that people do when they can't get a chance to test their ideas in the real world. Which means, in this case, way overdoing it.

Sail at night in the summer? Sigh. Well, maybe. We've got two Tahoe trips booked for next year, one in July and one in September. I noticed this year that the wind was calm every morning, kicked up in the afternoon, and was steady makes-the-boat-go in the evening. It would be pretty cool to come back to Meeks Bay from Emerald Bay under a steady wind, switch on the nav lights, cruise into the marina and -- turn around and head back out into the lake, just because.

[talbot]

Wow. I'd love to sail at Tahoe. My nephew sails, and lives in Walnut Creek. Maybe this summer...

We originally went out to look at a full moon a few years ago, prepared to row home in the evening. What we found, after years of scrambling to get in before dark, is that our lake has a night breeze that comes up about a half hour after sunset. Who knew? Anyway, now we go hunting for it. But we also have voracious mosquitos. Hence the motor, just in case. And then once you have the battery in place, why not replace those little flashlight running lights with regular 2-mi. nav lights? And as long as you're in there running the light circuit, why not hook up the compass? You know how it goes. It all begins with a romantic evening under the moon, and next thing you know, you have all sorts of responsibilities you didn't expect.

[K.C. Walker]

You know how it goes. It all begins with a romantic evening under the moon, and next thing you know, you have all sorts of responsibilities you didn't expect.

LOL

[GreenLake]

Lake breezes.

Almost every summer I sail across a lake here to visit friends on the other shore. Daytime summer winds are weak, often fickle, and more than once I've drifted in on the last sighs of a dying breeze. The friends, non-sailors to the last, are concerned whether I will make it home and I get offers of a lift home so I can come back another day and sail the boat back. Invariably, after dinner and a glass or two, the night breeze springs up. Gentle but persistent. By that time, the stars or moon are out, city lights dot the shore, and I have the lake to myself. I push off, trim the sails, arrest the tiller, and staying on the same tack, enjoy a steady reach home.

The motor comes out a bit under a bridge and a across a mirror-smooth sheltered bay, and by that time, I'm glad it's electric and doesn't disrupt the silent glide. Closer to the docks, the wind funnels and i have a few minutes of vigorous upwind work to break me out of my reverie, but then I'm among the shelter of the other boats, coasting on momentum to a gentle stop. It's 2 a.m., my friends are long asleep and no longer wondering whether I made it when I finally have the boat de-rigged and on the trailer.

Night sailing, the way I love it.

[talbot]

Back to battery boxes for a moment. Not sure I was clear that you don't just stack two intact boxes. You cut the top off of one and the bottom off the other, and then fit them together so they make a telescoping well that adjusts itself to the exact distance and angle between the cuddy floor and the hull. It also gets the battery weight as low as possible without blocking the bilge drainage. Once the box is position, you glue and rivet the two sections together to make a single deep well. I used Series 24 boxes. Here's a rough schematic of the installation--not to scale. In real life all the fiberglass parts and layers are the same color, but I tinted them in the graphic so you can tell them apart.

Battery box installation schematic

batteryboxSm.jpg (74.16 KiB) Viewed 9419 times

[Salty Dog]

Wow! nice graphics

SD

[Alan]

Please allow me to add my "wow!" That's a really nice drawing, judging on esthetics as well as on informational clarity.

I'm thinking of having one battery on each side of the centerboard trunk, just forward of the cuddy bulkhead. I've been stuck on the problem of supporting the cuddy floor once the battery holes are cut. The custom-height battery box with the plywood lip is a fine solution.

[GreenLake]

Talbot, you're hired! Can we get you to diagram stuff for the rest of us?

One design element I am wondering about is the hull-reinforcement. Now on the DS1, there's a keelson in that area, so you don't actually have a flat surface for any tray to rest on, but even without that, it would seem to me that the area is plenty strong and shouldn't require reinforcements.

However, I'm happy to learn, so what I'm curious is whether you added the glass layers just on principle, or whether you checked for flex or other indicators. Or are your hull-reinforcements intended to act as stiffeners, independent of the battery project.

[talbot]

I shouldn’t have gotten involved in this thread. Now I can’t stop thinking about the design issues of two batteries below deck. A couple of things that make my schematic more colorful than useful:
1. Two batteries sideways will sit very high in the bilge because of where their outer edges will contact the sloping sides of the hull. You may not need double boxes. You could still cut and then reattach the lower half of the boxes if you wanted the self-leveling effect.
2. That tray under the boxes is much more important with two batteries. For me, it just serves as a passive restraint the keep the battery box from moving fore and aft and eventually cracking the floor around the lip. The weight of the battery is on the reinforcing pads, and the box is flimsy—maybe three layers of light fabric molded around the base of the battery box. Your tray would bridge the deep part of the keel and would have to support the weight of the inside edges of the batteries. I would consider using one double battery box with a continuous floor.
3. Two boxes or a double box set sideways to avoid the under-floor stringer will create a low wall across the middle half of the cuddy. It will be harder to slip heavy objects like a camping duffle into the cabin or to retrieve bulky objects that are forward of the mast.
4. If you put the batteries side by side with their long axes aligned with the keel to save space, you will have to take out a pretty big section of the stringer. I found the hardest part of the whole job was repairing the damage I did to the floor support. In fact, I never got it right. This winter, with the boat upside down in the garage, I’m cutting away some of my old crappy work and replacing it. The cuddy floor is really wimpy, and you wouldn’t want it to break under you while you’re in there doing the wiring.
5. If you can put additional support into the floor, it might be able to take more of the weight. After my battery box was precisely aligned, my last step before installation was to put D-section marine weather stripping around the underside of the lip. When the box is empty, its base actually clears the tray because the box is floating on the gasket between the lip and floor. When the battery is aboard, the foam is compressed, but some of the weight is still distributed between the floor and hull. Even with the reinforced hull, it creeps me out to think of 50 lbs of lead bearing on such a small area. That part of the hull is already notorious for stress failures.
6. I didn’t mention this, but the lip is bolted directly to the floor. You obviously can’t reach inside to thread nuts once the box fills the opening, so I installed permanent T-nuts under the floor, fiberglassed in place.

As to Greenlake's question about reinforcement: On the DS II, the keelson begins just forward of the mast. But in any case, the tray is the flat support surface. It gets those two extra layers underneath because all the battery weight is ultimately transmitted to the hull through its two outside edges. The main hull reinforcement was initiated by the battery project, but I was also aware (from Roger's book and from reports on the forum), that the area forward of the CB trunk is prone to cracks caused by stresses from the CB. So I was happy to reinforce it. Once the floor is open, that's the easiest part of the whole job.