OK, so I thought I'd update this thread. This weekend I took the T out for a spin on her first 'real big lake', that is to say anything where she could get up to full speed and sink deeper than I want to dive. Everything went pretty well for about an hour... Which suggests something didn't. Well, you're right. I should make mention now that this is the first ship I've driven with what I call a 'dry motor', that is to say... the motor will only get water cooling once the ship has taken significant damage. About an hour into my trials, I noticed smoke coming out on occasion.. usually when the ship went from full stop to full speed. So I assumed the motor was really hot, which was true, and what I saw was water steaming off... which I still believe is true. Additionally the ship's top speed was slowing down; which I attributed to a hot motor and perhaps a draining battery... I pulled the ship into port and tested my theory by splashing water on the motor. It immediately puffed steam that looked like what I was seeing; so I believed I was correct. What I didn't think about is when the motor coils which are very hot get hit with cold water... the coils will start to fatigue, and will eventually fail. Well it failed. The coil failed so catastrophically that it shorted itself. Which intern produced zero load on the ESC (WHICH IS FUSED BTW) but apparently the fuse couldn't react fast enough. Because my poor beloved MTRONIKS40 ESC is most decidedly destroyed too. To make matters worse, some time during the trial my prop gave up two blades to the pond. Which is completely strange, because as far as I could tell... I hit ABSOLUTELY NOTHING! No twigs, rocks, trees. The only possibility is fishing line... which I would not have seen. So now I'm out a prop, motor, and an ESC! (Thank you Greg, for donating a fan-cooled motor to the dumb Justin fund!) So, I'm hoping a fan based motor will solve the issue and keep the motor nice and cool as soon as I get her up and running again. Because if it doesn't then I guess I'll have to go back to what I did on the Iowa and build a water pump into the drive system. I must admit, that was really cool. Additionally I've been on the horn to England, and MTRONIKS is going to repair (perhaps for free) my ESC... as this is its first real test in my boat. I forgot to do it today, but I'm going to spend a significant amount of time researching fast blow fuses. My hope is to find one that is remotely (or automatically) resettable. That way if I pop a fuse (which I did on the Alsace all the time); it will auto reset for me. I have a resettable fuse now, but I have to manually reset it... which is good as I don't need to carry fuses, but bad in that I'm a sitting duck.
I have never run across a self resetting fast trip breaker. there are self resetting thermal circuit breakers, and remote "on command" resetting breakers available. The latter may be able to act fast enough, the former, no way.
Yeah, I'm going to talk to the guys @ work.. I just forgot today. I'm sure they'll know of something.
That would certainly work... but I'm not going with a mechanical solution. Things just break too easily on boats.
What are you running for a motor in her? I have a 30 amp fuse on the front of my Mtroniks 40, The packaging tells you to run one a little bit smaller than max rating. Also how tight is the motor/shaft to spin, a bind will definitly put a load on. Another option is to water cool the motor. People wrap copper tube around the motor and have a inlet in the bottom of the boat and a exit at the stern for cooling.
What are you running for drive motor(s)? How freely does the prop shaft turn in the stuffing tube? I have had fishing line wrapped around my Bismarck prop but never had the blades shear off from a line. What kind of props are you using? I use a large Johnshon HC970 motor to power a single large prop no esc, no cooling system no gears, direct drive. The only speed adjustment is a speed adjust coil resistor. My Yamato uses cooling coils and water pickup tubes. This system has worked flawless for about 9 yrs and still going. I never had a motor burn out under this system. A binding shaft or tight shaft will certaintly increase the load on a motor and cause it to overheat very quickly. A underpowered motor or overpowered will also create heat and draw more amps. Are the motors high rpm or torque? Possible that the prop being wrapped in fishing line caused excessive resistance increaing the load on the motor which caused a domino effect on the remainder of the drive systems. Unfortunate but hey you got your ship back .
This is a Big Gun boat, right? I have difficulty believing that a boat that slow is going to overheat a motor. Us high speed fast gunners, yes, but the slower BG boats, No! Somethng else must be envolved (binding shaft, etc.) Marty
Not a big gun boat, built to IRCWCC spec. I also have a 30 amp fuse on the front of my Mtroniks 40 motor/shaft spins very freely, well oiled machine. water cool/cooling tubes... I have done this before, and am trying not add that complexity; but not afraid of it if I must. drive motor; smaller than 550... capable of 40Amps stall. More than enough power, obviously not enough cooling.
I'm running a 970 in mine. I bet that little motor is working too hard. I push my carrier with two 550's and that gets warm. Just a thought,,,,
Bob Amend runs a 970 in his Bismarck too. I'd imagine your motor is too small. If you can't find a 970 or comparable motor, BC makes a "two motors to one shaft" suitable for using 2 550s on a single shaft that might be worth your time to check out as well.
Yup. Strikemodels.com sells the 970. I got one on order and have one ready to install in my Bismarck again. Harbourmodels. com sells them too.
No doubt is is more powerful... question is, why? Why would you need that kind of power? If this was a car, I'd agree... but it's not. Its a boat. You can't go any faster than your set speed, and I can't imagine a monster like that is easy on the amps! If I had a real weed problem, or I wanted to cut through fishing line... sure....
Because it has plenty of torque to power through moss. It has plenty of torque to power your model on a single shaft effiecinelty through direct drive without the need of gears to gear down a higher rpm or bring up the torque on a smaller motor. One motor, one shaft direct. Plenty of muscle. The only speed adjuster I use is a regular slide adjust resistor. I set it it at one end so that the model at full displacement will not go beyond 24 seconds for fast gun,but at the same time it does not lose the thrust at the lower speed. I can use a single larger prop to prople the model instead of 3 smaller props. The wiring is much simpler and much easier to troubleshoot. THE MOTOR LASTS an awefull long time. I ran mine for 6yrs straight hard battling and running. I messed it up by spraying WD-40 in it to lubricate. I replaced it and it ran for another 9 years. It's just a great motor for a ship on a single shaft like Bismarck. Running time is great too, usually 2.5 to 3 hrs on a single 12v 7amp ora 6v12amp depending on the motor and use. That one motor draws about the same amps as 2 , 600s. The motor is very easy to swap out if you have a problem but it is so robust you would rarely ever need to. Simple and efficient
