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Post by JohnV on May 19, 2020 16:27:48 GMT
look forward to hearing a trip report on the high speed all electric beer collection/consumption platform
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Post by Deleted on May 19, 2020 16:41:16 GMT
Yes I pretty much got that. This is a 40+ I built largely from spare parts left over from a quest to build the nicest model 55 (a later 40+) ever. However I got a bit carried away and gave it a stainless driveshaft casing, and then also a stainless exhaust tube due to the difficulty in finding un-dented originals. The gearbox and prop are the result of hours of abrading and polishing... The bit circled is a mod concept borrowed from the 102 design where the idea is the exhaust gases are cooled and quietened by the cooling water ejected from the block. Normally on a 40 the exhaust tube has a hole drilled in it to relieve back-pressure, but it also increases the noise level. Since this tube was home-made I didn't drill it so its a bit quieter. The motor was also completely rebuilt, block repainted, new piston, rings, etc. You can't see it in this pic but the ignition was upgraded to electronic and a recoil start unit added (luxury). I also gave it a plastic tank for longer range. It now has an endurance of around two hours at full throttle. Which is nice. The 'nicest model 55 ever' project has got sidelined again while I am working on another modded 40+ with a sealed gearbox...and I have yet to finish the shiny 102 but its almost there. Since I'm trying to make that one as authentic as possible, its taking ages. The next job is adding some replacement decals to the fuel tank. its a kind of madness. Sometimes you hear about someone who announces a project to make an electric outboard that looks like a Seagull in every way but I've never heard of anyone actually crossing the finish-line...its an interesting idea though.
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Post by Deleted on May 19, 2020 17:53:59 GMT
look forward to hearing a trip report on the high speed all electric beer collection/consumption platform
I might even have to get my extremely anorakish 'eagletree' data logger out and plot graphs of amps and speed over ground. That would be interesting in order to extrapolate the most efficient speed. Seems probable that this will have to be done actually assuming the old hardware is still working ok !
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Post by Deleted on May 19, 2020 18:01:50 GMT
Sometimes you hear about someone who announces a project to make an electric outboard that looks like a Seagull in every way but I've never heard of anyone actually crossing the finish-line...its an interesting idea though. People approach it all wrong. They assume you have to put the motor on the top. With modern brushless motors you can get the equivalent power out of a motor which would be small enough to shoe-horn into the lower gearcase itself. Looking at the case on the 102 I reckon you could get a 63xx motor in there comfortably. Would need some machining skills and parts but I reckon it would go. Lead the wires up the driveshaft tube. Build the speed controller and a small lithium pack into the fuel tank, leave the rest of the motor unmolested. The flywheel would not turn... You could build a larger lithium pack into a remote fuel tank and run the lead through a fuel hose. That's how I would do it anyway. They are quite impressively powerful the 63xx motors. Not barge pushers and I don't know how good they are on a seagull prop but they can shift some water with the plane props. In fact for a Century conversion I'm wondering about building the speed controller into a sealed housing inside the exhaust leg then fill the fuel tank with a lithium pack of some sort. Nice project but I don't have the skill to make it. I can do ideas but when it comes to making stuff it's always a bit of a bodge.
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Post by Deleted on May 19, 2020 18:37:25 GMT
I find it counter-intuitive to put the electric motor in the water...are they that watertight? Anyway if the idea was to make it appear to be a Seagull possibly the best gearbox casing would be the later 'sealed' type (a bit more length / room). I have a knackered one that would be a good candidate.
Without access to a workshop things could be tricky. But some of the time at least, when making parts accept foreign components, fibreglass is wonderful stuff. You can make it any shape you like really easily. All it takes is patience and sandpaper. I'm already thinking of a wooden plug in the silencer sealed with maybe fibreglass. I could show you a so-called long-distance brass tank which could be cut open and then closed like that to make it house a battery...
Can you provide any pics of this 'speed controller' of which you speak?
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Post by Deleted on May 19, 2020 19:57:59 GMT
I'd use a hobby esc. Would want to be removeable for replacement if it fries but for experimental work something like this should do it. www.ebay.co.uk/itm/V-GOOD-40A-2-6S-32-Bit-Brushless-ESC-with-5A-SBEC-for-Fixed-Wing-RC-AirplaneF9J9-/224007730833Say 30 amp at 20v that's just under a horsepower. Could go for a better one later on. Not a large item and I think it would benefit from being in a sealed enclosure underwater for cooling. Bottom of the exhaust tube seems ideal. These are cheap generics but for good stuff "Castle Creations" seem to have a good reputation.. Control it with a £5 servo tester like this www.ebay.co.uk/itm/RC-Servo-Tester-Checker-/324156626701I cut off all except 3 pins and wrapped one of these in glue heatshrink. It also works as a bodged dead man's handle you hold it in your hand and control speed with it then if you fall out of boat it detaches and the motor stops as esc is no longer receiving a signal. Told you I was a bodge artist The one I have used in a previous electric kayak/duck punt thing was a hobbywing 40a esc onto a 6354 motor 236kv. Running on 12v that was pretty good but only about 350 watts before it breaks the weak link coupling I fitted. Enough for a kayak but if it was to be equivalent of a seagull outboard you'd probably want a higher voltage and lower kv rating for the motor.
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Post by Deleted on May 19, 2020 20:05:36 GMT
Some of the more recent electric outboard offerings seem to be adopting the low profile long thin (56115 / 56200) motors in the lower unit.
Plus of course the efoil surfboards.
Electric should be quiet. Putting the motor under water helps a lot with this aim.
I'm sure it you sell people noisy electric motors they tell their mates they are too noisy.
Seems awkward to silence a top mounted motor and the associated driveline..
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Post by Deleted on May 20, 2020 8:52:31 GMT
What would you say is the best current manufacturer / model for sale? Also 'best' is a bit subjective - so why you think so is of interest too.
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Post by Deleted on May 20, 2020 10:35:59 GMT
You mean ESC?
I've never splashed out on an expensive one always used generics which I seem to burn occasionally due to incompetence.
I've read good reports about Castle Creations but not sure which one would be suitable as I just so cheap stuff.
For the electric kayak I used a Hobbywing 60a controller which seemed happy. In a dry location..
Not used an expensive one as a bit of a cheapskate but I might splash out on one of the higher price ones if it seems the right plan later.
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Post by Deleted on May 20, 2020 10:38:07 GMT
If you meant outboard itself the one I would buy for the dinghy would be the Epropulsion 1kw model. It's a nice tidy quiet unit direct drive submerged motor pod..
I've not used one though. £1300 is expensive really and they are a bit nickable as well.
Even Torqeedo have got the message and gone for direct drive now. Their earlier ones had nasty little planet gearboxes which give out a humming noise. Direct drive is much much quieter.
My dinghy motor is a Minn Kota 36v pod on a shaft and a cheap PWM controller onto a ebike battery. Total about £550 of hardware. Bullet proof old school big heavy motor but not that efficient. It deals with all the rubbish in the inner city ditch so I'm happy with it. For the Thames a more refined type of unit would be worth investing in or making as less shite in there.
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Post by Deleted on May 20, 2020 10:46:22 GMT
The brushless motors are quite small really. This is a 6374 which will push my wide stable kayak fast enough to make waves which rock narrow boats around... In fact the actual motor in the kayak is a 6354 so somewhat less powerful than this one but more or less same general idea. Power to size ratio on these is mind bending.
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Post by Deleted on May 20, 2020 12:53:58 GMT
And that is a waterproof unit? ETA Assuming it is, and the output shaft is where you would attach the prop... 1. How do you attach the prop? 2. How do you waterproof the power terminals? It looks like it would fit snugly inside a Seagull fixed-drive lower unit which would be useful because the driveshaft casing tube fits neatly onto it. Fabricating something to fix to the top of it to house the controls would be a piece of cake. Standard transom bracket... You just need part numbers 2, 3, 4, and 12 (and the gearbox). Bin the rest. How big a battery would be needed for about two hours run-time?
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Post by Deleted on May 20, 2020 14:01:44 GMT
That motor is not sealed. It would need mounting in a sealed container. I think the seagull lower unit can be sealed if needed.
I suppose if you were on average using 400 watts electric for pootling around in a dinghy you would need to have about 800wh for two hours so on 36v that must be about 25ah. That's quite a large bank actually. Too big to get into the fuel tank. Maybe look at the exhaust leg for extra battery capacity?
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Post by Deleted on May 20, 2020 14:42:12 GMT
I would cut the bit of the water pump housing that has the lug for the silencer off in order that you had greater clearance for a larger diameter prop. This would also get rid of one of Seagull's design flaws - you can't rotate a Seagull through 360 degrees due to the twin-tube design...but maybe that's not a problem if the electric motor is reversible. Then fit a box like this for all the other gubbins to the top somehow: Some sort of base plate would have to fabricated to support the weight. I imagine you could fit a small AGM battery in there without too much bother, but looking at that box it wouldn't be difficult to build in a lead for an external battery. Then all you need is a tiller... BTW, yes you could seal the gearbox but it wouldn't be as easy as you think. For one thing you would need to come up with a pretty good way of sealing the output shaft. Much better to have a sealed unit to begin with, I think. Also there are some internal structures in the gearbox which would need to be ground away, and the pinion gear would need to be extracted - a bit of a pig but not impossible, and again you would need some type of gland to allow the wiring to pass through the driveshaft tube up to the controller.
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Post by Deleted on May 20, 2020 20:59:10 GMT
Perhaps it is best to let sleeping dogs lie. And let seagulls be seagulls.
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