For some reason your photo did not make it through....
My control levers are not Volvo, they are Edson on the steering pedestal just below the compass. There were two levers for the diesel, one on the left for shift (FWD-REV) and one on the right for throttle (FAST_SLOW). I chose the shift lever on the left to connect to the Curtis throttle below deck on the other end of the Morse cable. Either would have worked well. It made more sense for it to say FWD-REV than FAST-SLOW. But I keep reaching to the wrong side after 20 years with the Volvo throttle to the right. You can the the Curtis throttle and the Morse cable connected to it in that wide photo of my motor compartment. It's up at the top on the left over the controller. I'll get a better photo tomorrow.
As it is the lever I have is very good and in a very good location. But I am not a fan of the wheel and if I had trouble with it I would happily toss it overboard and convert the boat to tiller (they came both ways). R=1/P applies. For now that is a low priority. The wheel is forward in the cockpit and I find that preferable as the mainsheet, the traveler, and the jib winches are in easy reach. And non-sailor guests can be seated all the way aft in the cockpit and be completely out of the way for boat handling.
I would not consider having the Curtis unit above deck. It is not suited to exposure to the weather. You could put it in a housing but I think it is better below deck with a linkage of some sort. Especially in a salt water environment. And I like the idea of having a relatively massive or husky lever with a lot of feel to it rather than a delicate little lever or a wee little knob. Moving 6-1/2 tons of boat should have a little more to it than a tiny knob or lever. Even if the actual control (the throttle) is a wee little potentiometer.
By the way, one of the members at my club has a Maxi Mixer. A very interesting boat though somewhat uncommon in these waters. It's for sale if your interested. He's in a bargaining mood.
Dan Pfeiffer
On 2021-07-25 10:52 pm, Carsten via groups.io wrote:
About the regulator/throttle :If you like the position of the Volvo handle (which I don't), it might be possible to mount a housing in the lazarette to connect the Curtis to the handle shaft directly.My idea is to mount my Curtis on top of the tiller, near the base. The handle will move in the axial direction of the boat, so logically forward will be ahead, and reverse will be astern.When maneuvering (especially when berthing), it's so easy to forget the right direction when operating the Volvo handle, that (in my case) shifts direction port-starboard.See photo, where the 3-button box is to be replaced with the Curtis throttle.
On Monday, 26 July 2021, 09:56:31 GMT+8, Dan Pfeiffer <dan@pfeiffer.net> wrote:The throttle unit from Thunderstruck is electronic. Probably an optical device?? Not sure. It is the Curtis ET-134.
Dan Pfeiffer
https://www.thunderstruck-ev.com/curtis-et-134.html
But there is a mechanical linkage from the pedestal mounted lever in the cockpit to the Curtis unit below deck. It is the same lever that was for gear shifting on the Volvo. I made a mount for the Curtis throttle to connect it to the Morse cable from the lever on the pedestal. All of those linkages make the throttle feel a bit vague and it is difficult to feel the neutral detent in the Curtis throttle.
My cooling system is not reaching 100C. I was just saying the hose should be able to take that. Or maybe about 120C to have a little extra margin just in case. But the 65C hose is not going to be adequate.
I have been checking temps with my Laser IR thermometer. It is unreliable on shiny surfaces. For those I can put on some tape. I don't know that I get any more useful info from the temperature of the motor or controller case compared to what the internal sensors report. It is handy to check the stuffing box and thrust bearing housing and the cooling system parts.
On 2021-07-25 1:10 pm, Carsten via groups.io wrote:
Dan, you can make a wifi antenna. It's easy.Your throttle is not electronic ?If your cooling system goes to 100C then something is wrong and may explode.I suggest a temperature gauge to the system.Another thing, you may check the different part surfaces with a lasergun thermometer when running.Happy sailing, Dan
På man., den 26. jul. 2021 klokken 0:57, Dan Pfeiffer<dan@pfeiffer.net> skrev:All good Questions Carsten. And good suggestions. I have done the gopro on a stick at the dock to inspect the bottom. I loose the wifi connection after it's about a foot underwater but it keeps recording.
I have tried a bit of reverse then to neutral to get the prop set the other way so it will feather while still moving forward. I have had mixed results. But I have only been at this for a couple weeks so I need to do more experimenting. One problem is be the vagueness of the feel of the lever control. The neutral detent in the throttle unit is hard to feel from the lever in the cockpit through the Morse cable connection. So its a bit too easy when shifting to neutral to skip over and into the opposite direction.Yes, adding a bit of power to tack has been handy. I have only done that in light (4-7) wind with chop conditions which are a bit troublesome for tacking. I also used a little bit of motor to maintain 4-5 in those conditions rather than 2-3 I would get with just sail. Worked well. But adding the power instantly with the feathering prop still requires that you mind the wind up of the motor until the prop blades are fully rotated on the hub. The acceleration curves of the controller will help with that.
I may have overstate the Volvo idle. Probably more like 800 looking back at my notes. And I may have set it there to get past the vibration at very low RPM. Mine was a 2 cyl Volvo MD11. My notes on speed vs rpm started at 900. I may have skipped the lower RPM in recording that. That is still a lot faster than the slow speed you can run the electric at.
I will probably switch that that same hose I used for raw water which is basically the auto type but with a marine rating (Trident). I will add that bleed valve at the controller inlet and I may re-mount the controller lower on the bulkhead so there is more space above it in the fill hose to get the coolant level higher above the high point in the system (controller). I will also look into adding a sight tube that is OK to 100C so I can monitor for bubbles. In the mean time I'll keep the power down to keep temps under 65C. And that seems to be under 6 kts. That's where I would operate normally anyway.
Another thing I probably should have had was a drain valve on the coolant system. It might help to keep from making a mess when re-configuring the system. But I was really trying to keep the parts count to a minimum to honor the R=1/P relationship I try to live by.
R=1/P
R is reliability
P is number of parts
The goal in design should be less than one part.
Dan Pfeiffer
On 2021-07-25 3:47 am, Carsten via groups.io wrote:
Dan, I envy you to just go for a sail !For feathering, perhaps set sail, rev the motor up to 6 knots and set it to neutral. Then it should feather.Does it begin to spin in short surges (unfeathers), if it is already feathered at higher speed, and you slow down ?Another thing, when you tack, you can use the instantly available motor to keep up the speed, so it doesn't "die", when turning through the straight headwind. My boat dies easily in light winds, so I am looking forward to that.Keep the motor running up to 6 knots, and set to neutral for feathering. Just an idea.If you want to check what's going on underneath, you could mount a Gopro with Wifi on a stick (aluminum tube), and see what happens on your smartphone :-) See Youtube for connecting to wifi.Also nice for checking growth.When sailing, of course you'll need to secure the stick properly !My MD6A Volvo idles at 600 rpm. 1100 seems a lot ?You can use automotive hoses for the cooling system, and I think you already used that for the raw water ?At the top inlet (the blue) hose of the controller, you can insert a valve to release the air trapped there.Run the pump a bit when topping up, so it circulates.Again, just an idea.CarstenOn Sunday, 25 July 2021, 13:13:46 GMT+8, Dan Pfeiffer <dan@pfeiffer.net> wrote:I have a little more info on props and performance in general. I got out for an excellent sail today in 15-20 kts. While sailing at a sustained 7.5 knots I checked the propeller and it was not spinning so it found its way to being feathered all on its own. All I did was put the motor control to neutral. At slower and more typical sailing speeds of 3-5 kts it seems to spin in short surges. So there is more to learn about the prop behavior but it is able to fully feather and stay that way with more boat speed.
And another thing about how the boat handles now compared to the diesel. I can operate the electric at very slow speeds. The diesel could not do that. It idled at 1100 rpm which translated to 550 prop RPM and a bit better than 3 kts. I can operated the electric at much slower RPM. The steerage suffers greatly so it's debatable how useful that is but it is a distinct difference.
Also I will need to upgrade the hoses I used for the cooling system. They turn out to be rated for only to 65C and that isn't enough for high powered operation. That's only 15C beyond the set point to turn on cooling. I used Trident reinforced water hose. I'll need something made as a heater hose. The transparent hose was very handy in chasing bubbles out of the system. But keeping the hoses from melting will be more useful.
Dan Pfeiffer
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