1986 260 Sundancer Project

I am considering putting together a 260 Sundancer Hybrid utilizing a variety of products in my scrap yard. To begin with I have a few electric fork lift motors,8 800 amp industrial forklift batteries and a motorless Sundancer with output assembly.After mating a forklift motor to the output assembly I want to mount a new 400 watt solar kit and a new 400 watt wind generator. In case I can't find enough wind or sun I will also be carrying a new 5kw diesel generator wired to charge the batteries. My question is will I get stuck in the middle of the channel and wash up on the rocks because the combined input of the genset, solar panel and windmill can't generate enough power ?

 

I am interested to see what you come up with. Someone has to start trying if we are to push the limits of hybrid tech.

I fear you will not have nearly enough power/battery reserve for the ~150 hp it takes to run that hull at planing speed so it will be a bit of a dog at sub planing speed...

 

Interesting project Questor.
Change the name to Suncrawler and use your boat accordingly.
What are the specs of your fork lift motors?

 

I'm not really interested in speed over 8 to 10 knots maximum, except in emergency. My first choice in a boat for all needs and wants would be a 30 to 40 foot trawler. I doubt that I will ever have enough money to either build or buy one. Older sport boat hulls are cheap to acquire and therefore expendable if something goes horribly wrong with modifications. I can envision the possibility of a rogue wind or wave ripping the solarpanel and 20 to 40 square feet of fibreglass out of the hull. I like the look of Sundancers and the privacy below deck in the evenings. In a heavily glassed trawler I'd feel like I was on TV every time I got up to go to the washroom in the middle of the night.Some would laugh at the concept of using a sport boat as a trawler but who cares, It works for me and I can afford it.

 

I'm nor very interested in speed. I'll have to look up the specs of the motors and batteries. Forklift motors have enough power to collapse the hulls if you're not careful. The problems in using them under heavy load are depletion of power and overheating. I used to have a friend in the fork lift industry that I lost track of. We discussed Hybrid cars extensively but he knew nothing about boats other than to express caution.

On the subject of boats he told me of a pair of shop experiments involving a brand new high capacity $65.000 forklift. First they loaded the forklift to maximum capacity and drove it in circles in the warehouse to see how long the batteries would last before discharge. After 8 hours they gave up the experiment , and placed the forklift on recharge. The next day they loaded the forklift to maximum capacity and started lifting the load 20 feet into the air, constantly raising and lowering it. After a little less than half an hour the electronic controller locked out the lift controls due to maximum battery depletion for safe operation. If the controller hadn't locked out at that point they would have shut down the experiment anyway because they were beginning to fear an electrical fire from the excess heat.

Based on those experiments he recommended extreme caution on utilizing his motors on a high speed boat. In rolling mode very little power is used but in constant lift at high load a lot of power is used and dangerously high heat is generated. He strenuously expressed the fear that excess heat could ignite or melt through surrounding fibregless.

 

Hi Q


For your batteries we need to know (ignore cold cranking and 20 hour rates) the "minutes of discharge" rates..like this:

http://www.lifelinebatteries.com/marineflyer.php?id=4

You'll notice:
- 25 amps for 315 minutes
-15 a for 555 minutes
-8 amps for 1200 minutes and you'll notice they are not an equal-at higher consumption there is more losses

Then we need to know the motor's output/requirements watts amps volts

You have 6400 amp hours worth of batteries.
Watts=amps x volts
watts= 6400 x 12
=77,000 watts/77 kw
So you have 100 hp roughly for one hour to full discharge or any ratio thereof keeping in mind that discharge rates are not linear.
If they're 24 or 48 volt well.....

If you're using 5000 watts to power your boat...your 5000 watt gen set will almost keep up.
Any usage above this and I'm sure you can see.

 

I 'm very disappointed in what I learned this afternoon.First is that the total rated output of the entire battery pack is only 225 Amps at 48 volts configuration for 1 hour when new. The batteries have been scrapped because they are below 80% of new output so the maximum potential would be 180 or less. Given the massive size and weight of the batteries I thought the potential output would be much higher. With a 5 MPH headwind and minor incoming wave resistance I don't think I would get out of the marina let alone get stuck in the middle of the channel.

Although the motors can blow away anything internal combustion on the quarter mile they are neither marine grade nor waterproof. Also they are not designed for continuous output at the levels required to push a boat non stop so they will definitely overheat.The last new hurdle is current limitation.Today I was looking more closely at the bracketing that secures the motors to the forklifts.There were 3 separate brackets each of which was about 3/4s of an inch thick. They are that thick because of the massive torque the motors are capable of.The 55 Amp limitting circutiry in the forklifts I have access to is too low for the boats demands. Running the motor without the limitting circuitry would probably rip the boat apart. I don't know how to calculate the limitting circuitry necessary for a boat and I doubt that I could afford or even find the components.

I have not been able to find out what the maximum potential of the motors are because they are tagged with intended use of the vehicle they are in.The same motor appears in different models with widely varying Amperage ratings on the tags. The supplier tells me that the tags are printed that way so that mechanics working without technical documents won't install limiters on a machine that exceed the capacities of the chassis.

In light of what I have learned here and from the supplier I don't believe that either the batteries or the motors are viable for what I had hoped.

 

I do not share your disappointment.
The batteries can hold more than 10 KW when new, now maybe 8, enough for several hours if you have no desire for speed. With a small generator and some help from sun and wind, you can quietly go wherever you want.

If the motor is limited at 55 Amps it can develop 2.6 KW at 100% duty cycle, if can provide twice that at 50% which is adequate if you're in no hurry. You mustn't compare any figures with those of an IC engine: your power plant is small, light and doesn't drain your wallet at a fuel station.

I would never recommend this if you had to buy the components, but you have obtained them for free, so in case of a failure the project involves no financial risk.

 

I wouldn't think the limiting circuitry would be critical since you are turning a propeller in a liquid. Even if the motor were not variable speed and came on full power I don't think it would matter as long as the drive unit was already engaged in the direction you wanted to go.

 

If you have everything free, it should be an interesting experiment. We need more new hybrid stuff. I don't see designing the cradle for the motor's torque as a showstopper at all. Will you have a cooling system for the motors?

(I'm out of my element talking electric, but am curious to see what you come up with.)

It does seem you'll need to expend (and store) noticeably more power pushing this 'chunky' hull that's made to plane through the water -- anyone have a good comparison of power required to push a hull like this vs. a proper slender non-stern-dragging displacement hull at these speeds?

 

The products aren't really free. I have to buy the derelict equipment and then consider the used value of the components.

Based on what I've learned in the past few days the boat needs at least 40 HP to overcome weather conditions normally found in the channels between Vancouver Island and the mainland. I'm now struggling with the concept of having a 40 HP Diesel primary drive alongside of an independent 5 kw electric drive system.The primary system would cover the major distances and stormy weather while the electric drive would cover the shorter ones.

It would be nice if Camano 31 hulls were as cheap to acquire as sport hulls.

 

I've been giving more thought to the viability of the forklift motor drive possibility.If while scrounging for scrap I seek out an intact derelict forklift that has a motor tagged at between 100 and 200 Amp at either 36 or 48 volts then I will have have all of the components necessary for a properly balanced 3.6 to 9.6 kw drive system. The heaviest industrial battery that I can pick up and carry has a 100 Amp/12 volt/ hour rating. Between the drive system and 4 100 Amp batteries I would be adding under 1.000 pounds to the boat.

In the private consumer world it seems that everything is over rated while all of my scrap buddies assure me that industrial electric products are understated.They claim that electric forklift components are understated by a factor of at least 4 to 1. Your local retail store doesn't care if they tick off a once in a lifetime time customer whereas industrial supply retailers care very deeply about repeat customers that spend hundreds of thousands or more per year on equipment and supplies.Their products must exceed your expectations. Assuming that this is true a 3.6 kw system should yield at least 7.2 kw.

With the addition of a 5 kw diesel genset and forced air-filtered cooling to overcome heat I think I should end up with a reliable, low speed stop and go cruiser that would satisfy most of my desires. On an average trip the 40 HP diesel would take me from the marina to the primary destination 10 to 30 miles away and the battery drive would handle the stop and go trolling during the days I'm there with intermittent genset charging.

 

Questor: I admire your quest but am really curious if you have done much boating out on the strait.

You may know that the channels have ebb and flood currents from 2.5 to 7 knots ..and if you look at the change between ebb and flood..the slack tide can be only 20 minutes in places,with 2+ knots coming on in 20 minutes either side.

i learned this the hard way,ocean kayaking, and barely survived.

If you don't have enough power you'll at best be waiting around for hours, and at worst you'll get into trouble.

You seem to be very mechanically and electrically inclined,but just one problem (overheated genset,motors,wire mishap),just one-and you'll pay $$$$$ for a tow.

Or if something worse happens-in these currents and cold waters you are done for.

 

I know the area can be very dangerous. If I do go ahead with major electric drive experiments I plan to have an engineer check it out before going in the water.

I had a friend that lost her father , uncle and 5 other people to poorly conceived and implemented boat modifications. They bought two identical former commercial boats with large heavy motors. They removed the heavy low lieing motors for interior development and installed new light weight motors closer to the back and at higher elevation. They made no ballast compensation for the modifications they made. They took both boats out of Vancouver believing that if anything happened to one boat, the other could come to the rescue. They got caught in rough weather. As they raced for shore one of the boats flipped. When the second boat turned to pick up the people from the first boat it also flipped. In the end seven out of nine people died.The court inquiry determined that the fatalities were caused by modifications changing the balance characteristics of the boat.

My friend carried the newspaper clippings in her wallet all the time I knew her. They have made a strong impression upon me.

I have been trying to find out what the actual channel current strengths are for quite a while. I had guessed that they would fall between 2 and 4 knots. If you add a heavy wind factor to a seven knot current I suspect that a 40 HP main drive would be overcome by the combined resistance. I thought 40 HP would be sufficient because that is the base HP of the Camano 31, which is one of my favorite boats.

It looks like the fuel saving 40 HP Diesel main drive has just crashed and burned as well as the formerly conceived 400 watt solar panel and 400 watt wind generator.

 

I'd feel terrible if I saw this on the news:"man rescued and found barely alive clinging to a log after his home built electric boat caught fire and sank this morning. He has been airlifted to VGH .........."

I think I remember that incident....just out of high school I think...'93 or '94.

This is just the straits area,consider how raunchy it can be up the coast in a few places with 7- 10 knots and almost zero slack....10 minutes later its running at 3-4 knots


But don't throw out the 40 hp yet...can you get a speed vs hp chart for that boat?

http://www.mobilegeographics.com:81/locations/4844.html