trolling motors

[Stump]

On to my next question, I'm looking at the Riptide saltwater 55lbs thrust motor. Is that about the right size? I'm concerned about getting out in the Sound and some of the currents that can come up, also, I am hoping to go up to the San Juans, and I would hate to get stuck halfway across with no wind...I really would rather not row that far if I can help it.

Ya' I know, an outboard would be a better bet but I just don't want to have to deal with the smell and noiseand the price of gas, that's the whole point in building a sailboat and not a motor cruiser.

Which leads nicely into battries. What and how many? I want to place them, or it, in the bow since I'm not a little guy and would hate to see my boat looking like a canoe when I sit in the stern. :oops: I also remember reading that the weight in the bow helps some in waves etc. what with steering and all.

[Stump]

Ray,

Thanks for the info..Just what I was looking for!!!!

Ya' I hear the straight can be bad, I was wondering if I might be better to head up the coast and then head due west...

All in all I beleave I had better get a whole lot more infomation before I try anything...

"course, I have to finish the boat first :oops:

[Stump]

Which is best for the weekender, the 36 or 42 inch shaft?

[Frank Hagan]

Ray, what's the difference in prop size?

[MikeStevenson]

Ray:

I'd wait a bit and do some tests with the 46lb. motor. We have run into the same phenomenon a bunch with our boats: The prop limits the top speed, but it does not limit the overall thrust. If you start motoring into a breeze, the 46lb. motor will start to work harder than it does when it's just pushing you around and it will keep you moving into the wind when the 24lb. will not. The fact that you're not going any faster in calm conditions will most likely be borne out in a low power consumption by your 46lb. motor; you'll see similar range to the 24lb. in calm conditions.

Mike

[MikeStevenson]

True; if it's blowing you might as well just sail, or motor-sail if you want to make a point close hauled and want a little extra push. That's what we doa lot (see the Cap'n Ply articles...)

Mike

[capt jake]

a 42 inch shaft might not exit the water when tilted forward hence causing more drag.

It will clear, if you build the mounting plate to extend slightly above the transom. I found that it is nice to stick it in the water a bit deeper than one would first think. It swells, etc, it keep the prop in the water.

I also mounted it as far outboard as possible, not a problem with hitting the rudder; and I have steered both independant of each other.

55amps for a 46#!!!!?? My 55# (Endura)only draws about 42 amps at max position. I have a 130 amp/hr battery, so I am just shy of the 3 hour mark at max throttle; though running at a lower setting extends this emensly.

BTW the grp 31-130 amp/hr battery I have in the forepeak weighs 66 pounds, not as much as I suspected.

Granted, if I had the dough for a long shaft outboard, I would probably do that. I have 3 short shafts (2, 4, and 5hp) but I think it would be a real pain to try to start them and control them being short shaft (too short for a Weekender). I am willing to part with any of these. I also have two additional 26# electrics!

[Frank Hagan]

The 46er had a slightly bigger prop. Larger diameter by maybe 1/2 inch.

I know that if I could find a prop with more pitch than the 46er would push the boat along faster.

Local Walmart does not have different pitch props though and I don't recall seeing any selection in West MarineCatalog...

I've only seen two props for the Minn Kotas, the standard and then a "Performance Prop" that WalMart carries here locally. Its also made by Minn Kota, and to be honest, I don't know what the difference is between them.

[JTam]

Try getting an aluminum prop. I've run into a few fisherman who believe that the plastic propeller on most trolling motors flex too much - wasting power. They suggested that I go to one of the sporting stores that cater to fishing and get an aluminum prop. I've seen them on the internet, but have yet to buy one.

[MikeStevenson]

The plastic props don't flex, I would imagine, but if you look at the pitch and shape, they're much more inclined to static thrust. This makes sense, as the motors are rated this way (not total power, but static thrust, unlike gas outboards), and static thrust is what's required to move a two-and-a-half ton fish boat around. All of this is working against us, who have light, easy-to-move boats. Another reason the plastic props develop low-end thrust is the propellor section; this is the thickness and shape of the blade looked at in cross-section. The plastic props are really thick, both to be stiff and to act as foils to produce thrust at low speed. The fat section stalls out quickly and so we lose thrust as the boats approach four knots. All of this is ideal for trolling motors, not so much for us.

Clearly, a new prop is needed. Ideally we should have larger diameter, higher-aspect-ratio props like the Cruising Design props for larger sailboats. I've been curious about screwing around with better props, but we've got too many other projects underway now to start yet another experiment. If we ever get back into the solar boats (which isn't unlikey with Elkhorn Slough nearby), I'll do more fiddling to get the efficiency up higher.

All of this gives people an idea of what's needed though for electric auxilliaries to be more useful. A lrage diameter prop will need more room to swing, but this could be worked around if it's mounted so that the prop is forward a little more than they are on normal trolling motors (you'd really not want to leave a large diameter prop in the water; way too much drag!

Mike

[MikeStevenson]

Back when we were doing the SoleXplors and the Hydroflier (which was originally slated to be electric), I was in more communication with EV and HPV (human powered vehicle) people. There were some great HPV props for the pedal hydrofoils, but the costs asked were too much to be worth trying. I got the general idea as to design though, and it's much like the Crusing Design props. I just wish I'd had a chance to "borrow" some of the laminar sections for underwater shapes which one of the builders had on his computers; pretty amazing stuff, but these were for submerged bodies, not displacement hulls. One of these days...

Mike

[Stump]

Sooo, how does the thrust affect operations in adverse contitions. My concern is not really gong fast, I just want to go into/thru/across, any type of current I get into, or into the wind if needed. I was assuming that with a higher thrust I could battle a larger current or wind, yes?

Not faster, just more umph.

[MikeStevenson]

Ray's right on: For current you need boat speed. For wind you need thrust.

Good thrust also helps when pulling another boat. We've towed Todd Schmitt's Drakken a few times when the wind died in San Diego and both boats would cruise along at 3.5 knots; hardly slower than one alone. Range probably would have suffered, but it was only a fifteen-twenty minute run.

The Sloexplors had about 36 or so mile range with no sun, but I don't know what the Weekender has now (different everything: boat, batts., motor.)

Mike

[Dave Williams]

Hello all,

This is an interesting thread. I have been mulling over electric power for the boat I am rebuilding and hope to relaunch soon. She is probably at least twice the dissplacement of a Weekender, double ended and no good place to mount an outboard. She does have nearly 20ft of waterline length and a very slippery shape. I thought it may be easier to hang an electric off a bracket than a fourstroke, and easier to stow when not needed. I suspect I'd need more thrust than the motors being disscussed here. I sort of came to the conclusion that it wasn't a real option since I am typicaly out for multiple days, although right now I have no power other than a big yuloh. Then I recently came across a REAL steal on a little Honda generator and it got me thinking again. Hmm. Maybe a little solar panal also. Lots of sun in the San Juans in the summer. I don't expect to motor against much current around here. Timing the tides is the game and if I'm out for several days I can wait for favorable current. Use it only if there is no wind and only then if my arms are tired out. It's amazing the distance you can cover with oars and favorable current. Any thoughts.

Capt. Jake and Stump,

I have spent a lot of time around the San Juans and further north and I can tell you that there many places where 3 to 4 knots of current is not uncommon. Some of the narrower passes can run faster.

Anyway, thanks all. I've enjoyed the conversation.

To kindness,

Dave

[MikeStevenson]

Interesting application. I suspect a slippery d-ender would get around very nicely.

The biggest problem with electric vehicles of any sort (cars, boats, planes) is the range. If you're comfortable with short range, you can have electric power easily. The little Topolino electric conversion I'm working on is a case in point: I'm looking for it to have a range of a bit over twenty miles. Most people wouldn't consider that as useful, but around here we have five little towns all about five miles apart; our usual errand-running loop takes about 13 miles at most.

In a boat, the range factor is more acute than would initially guess. The distances for a cruising sailboat's normal motoring range of a couple hundred miles or more are wildly more than batteries can reasonably handle (if you still want to have any space down below! - and that's for a big displacement boat. Our little light-weight boats can't carry anywhere near that.)

Obviously, we need to be content with "a kicker", something to help us get back a few miles after the wind dies in the evening. This is well within the capabilities of electric, and fits well with most people's actual needs. Not too many people are out doing deep-water crossings and needing to motor six hundred miles.

I mention all this because an uncle of mine has been debating an electric motor for his ULDB 40-footer for some time. He wants to be able to cruise the Pacific, so he needs range and that lets out the very sophisticated electric system he's worked out. The reality is that he only needs a 30-40 mile range as his life really doesn't include anything more than San Diego sailing right now.

I keep trying to get him to go with electric for short-range running, and add a hybrid generator system if he wants range. Mr. Williams is thinking along these lines and it's pretty valild. A small, quiet Honda could add tens of miles easily, and it's limited only by one's patience with the noise and by fuel capacity onboard. Solar is great, and we have really enjoyed the solar-electric boats we've made, but it's important to measure your needs and the available deck area you're willing to part with. They really only can supply a part of your needs, but that means your range is extended by that much. If you're willing to wait for a bit, you can fill your batteries back up in a couple of days with the right set-up.

Mike

[Frank Hagan]

There's a hydrogen fuel cell electric for larger boats being developed. Catalina has helped sponsor the research by donating a boat; I volunteered to crew it, but he has enough crew for weekends (at one time he needed more people willing to sail the boat while he was below tweaking the motors). Web site is at http://www.haveblue.com/

Hydrogen fuel cell technology makes a lot of sense in a sailboat, if you are extracting the hydrogen from the sea water. If you are making it using natual gas, I'm not sure there's much advantage (other than clean burning behind your boat).

[Dave Williams]

Thanks Mike and Frank for the quick replies.

As far as short range. I only picture running the motor for short times but if that happens several times during multiple days of cruising and there is no shore power to recharge then--well you get the picture. I do not like the idea of running the generator in a quiet anchorage. I have been angered by that to many times. Peace and quiet and all that.

I have maybe a space 3' x6' on the cabin top that could hold solar panals. I havn't researched what that would buy me as far as charging.

Suppose there were times when I was traveling using the motor and I ran the generator at the same time just to help support the batteries. How close would I be to keeping up with power loss. Wouldn't be anymore noise that running a fourstroke? Also get a little help from solar during those days. Otherwise use battery power only for in and out of the dock. I defy anyone to show me a trickier slip than mine for getting into; but it's cheap and the only show in town.

I really do use oars and sail whenever possible and since thats all I've had in the past I must have been pretty successful. Nothing more satisfying than sculling along out in the straits with a little current to help you along, listening and watching whats going on around, maybe dragging a fishing line, not really caring if you catch anything. Now that's living! I am however getting old!

Anyway thanks for your thoughts. I havn't been around this forum much but it looks great. I'm heading for the Queen Charlotte Islands tomorrow ,be gone for maybe six weeks, so I'll check in before then and otherwise all the best to you all.

Here's to kindness,

Dave

[Stump]

Dave -

Any information you could pass our way regarding information on the San Juans would be great...for example, in your opinion, what is the easiest way to get over to the islands from the main land. Shoot across the straight on a nice day or island hop from the coast to the east? Or perhaps trailer by ferry over and just start from there...I'm assuming that you can haul a trailer on the ferries of course. :oops:

If you could like to start a new topic on that stuff I for one would be greatful. 8)

Sounds like your in for a great trip, I'm assuming your singlehanding it?

Stop by more often, I would love to pick your brain...it won't hurt too much :twisted:

If you find a library near you at some point, drop us a line and tell us how your adventure is progressing... I must live vicariously until my own boat is completed.

peace

[Barry Pyeatt]

Launch from Anacortes, CapSante Marina and you are there. Easy access!

Of course if you want to sail all thru the islands you have some traveling to do, but there are lots of places to explore and lots of great overnight moorages thruout the islands.

Just watch the tidal schedules so you can figure the currents to watch between some of the islands.

Shouldn't be any problems as most all of it is protected waterways, get the cruising guide to the San Juans at any bookstore or West Marine.

[Stump]

excellent just the kind of stuff I need to know :!:

Thanks