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oops, you have a dx5 http://rcmuppet.blogspot.co.uk /2009/06/converting-spektrum-d x5e-from-mode-1-to.html This part of the discussion has nothing to do with your original question, so dont get confused!
mode 2 is generally considered the standard for UK, which is throttle on left stick. Mode 1 will be throttle on right stick. Spektrum dx6 or dx6i can be changed, its in the programming menu, however then a mechanical change needs to be made inside the transmitter First paragraph https://www.horizonhobby.com/p df/SPM6630-Manual_Addendum_Mod e_Change_EN.pdf
so, I'm trying to go over this in my head!😱 boat is going right way, stick is going right way, but the esc is actually reversed, as its on lower power, so if we change the motor wires, forward stick is now reverse, boat goes backwards, which is great for the esc, so now we need to reverse the channel, so the boat goes max forward, with forward stick, I think!🤔
Not Sure Doug, I think the boat is going the right way, with the right stick movement, its just not the right way around for max power, I was thinking what you say, but then the tx stick will be the wrong way around? Tinkering will be required I think!👍
My knowledge of "elecy" stuff is pretty limited, but I see that the model boat world (excluding racing types) is in the dark ages compared to planes, helis, cars etc when it comes to motors, batteries etc We have to reply a lot on testing, fiddling etc when it comes to gettingn a fast electric set up, in a scale heavy old wood boat😁 as there isnt much info out there. I tried testing over a long time, with one boat inparticular, and was lucky enough to have te use of eagle tree data logging, so could measure watts, amps, gps speed, voltage drop and so on, and analyse the resultsd on graphs etc back home on the pc. Its amazing to see that sometime s the fastest set up isnt always the best when you compare run time, amp draw, heat, voltage draw etc, and what "looks fast" sometimes isnt as fast as you thought😊 This boat for example, 6kg, ply construction will do 25mph, after that torque roll is kicking in, and it want to roll over. I tested props over a long time, using cheap plastic "X" props, and with the results was then able to get a more efficient and visually pleasing brass cleaver 3 blade one. Ranging from 50mm to 55mm the amp draw went from 45a to 90a using same batteries!, and teh highest amp draw prop didnt produce the fastest speed, all interesting stuff. The boat is similar to the OP perkassa. I also went from direct drive, to a geared drive, and can change the characteristics of the boat using different cheap gears, eg., small lake, dont need top speed, so change to acceleration, big lake, lets give up acceleration and have top speed, and so on👍
some esc's, particularly the cheap end ones (unfortunately those blue case ones have a rep to emit the black magic smoke) have a reduced reverse, to protect the model in the event of knocking the stick etc, so you don't get full tilt into the wall or bank😱 If you have the max speed in reverse, then you need to swop any two wires if its a brushless motor, and then reverse the channel on the transmitter, max speed is always forward, so its a fundamental set up issue here. You also need to ensure the stall or max amp draw is within the tolerances of the esc stated amperage, and be mindful that Chinese esc's generally have a very over exaggerated stated specification. In the set up programme of the esc, you can usually change the direction here, its going to take a bit of fiddling, but its achievable
something is fundamentally wrong here, there is no way that motor/esc/battery combo should have fried the esc in your perkassa. I have a number of large scale boats with a fast brushless set up, I pull almost 90 amps with one of them, on the initial acceleration, using 6 cells, 120a esc and (here is the difference) a 900kv brushless motor. The racing guys use high kv motors, they need the high revs, with a heavier boat like yours, you need the revs, but also the torque, which is a lower kv motor Before you do anything else, buy something like this http://www.4-max.co.uk/wattmet er-budget.htm really cheap, but saves you a fortune. As many of previous posts have said, you need to measure what is going on, for example, the specs of you motor say max current is 100amps, you need to measure your amp draw. You know the esc was 160a with a burst of 200a, so should have been well within the capabilities of your set up, but we cant see the prop. If its too big, and too coarse, particularly holding the boat, the amp burst would have had to exceed 160a to pop the esc, which is also well over the motor specs. I doubt the hobby shop will do anything, as the fault could have been a multitude of things, Personally, I think that motor is way too high KV, and I'm saying this from experience of large, heavy scale boats, with fast brushless set ups. I would have expected it to rev very high, but not deliver a really fast top speed, but I could be wrong. Shame really as its quite an expensive set up there. Are you sure about the facts, holding that boat, and max throttle must have been pulling your arm off, I cant hold any of mine😱
to add to that, its also regarded as good practise to balance charge the lipo, using the balance lead, and and appropriate lipo charger, I believe all lipo chargers have this facility. This means the cells are all equal when fully charged, and you can view this on the charger display. It also means that none of the cells will be overcharged, and risk fire etc. The down side is that as the charger enters the final stage of balancing and achieving fully charged, it takes a while, as the current reduces, so patience is a virtue, and never leave unattended whilst charging, that applies to all chemistry, I have seem a nihm explode due to over charging, its not just this lipo myth that is risky!😉
Hi Rob, personally I would keep the clevises, it will make fine tuning much easier than the ball and socket. As Dave said its about 35 degrees, but you radio can play a big part here. I use a spectrum dx6i. So I have dual rates and exponential settings, and use these when at speed, and then going slow. I wont bore you with this as you may know what I am talking about, if not let me know Ill explain, but I need to know if your radio accommodates this, virtually all digital transmitters will have this. Paul
nasraf, have you not got that the wrong way around? The higher the c rating (rate of discharge) is the quicker the lipo can deliver? , you state the opposite, Otherwise why would we spend extra bucks on a higher c rated lipo? FDor example, I have a certain model plane, if I fly with a 3300mah 25c lipo, I expect and get a shorter flight time, and less power when wanting to do stunts, as the battery is depleting. I know this due to the fact I have a lipo low voltage alarm plugged in, set at a generous 3.7v per cell. So I then fly with a 5000mah 40c pack, the flight time is longer, and the stunts will last longer into the pack due to higher c rating. OK, battery make, and age etc come into play, but this is a generalisation. Going back to the original post, in simple terms, the higher the mah (amp per hour is a simple move the decimal place) and high the c rating, the faster the boat will run, and the longer it will last. Correct me if I'm wrong?👍
Hi Steve, can you leave your alarm plugged into the balance lead as you run the boat, this is what you need, so you get an alarm when the boat is running signifying playtime is over😁 If its not, then consider for the money my link, or similar, I have a few, and use them on planes, helis, boats, it will pay for itself time and time over to stop you over discharging the lipo 👍
thats prety much it Alan, but be warned, chinese c rating and mah tends to be overstated, the bottom figure being exagerated, and the top one really only there for very short bursts, its more abount the make of the lipo If your present packs have puffed, one or more of the cells has either over discharged, or couldnt take the draw, once puffed, its pretty much had it. I have used slightly puffed lipos oin a boat, but would never use them in a plane, its just not worth the risk if it fails, and it probably will
I hate wood! cant work with it, its always a disaster😱 Plastic for me, cuts easy, glues easy, cheap, pretty much paint ready, light. I refurbished my fireboat with it, and did the PCF build with it, also, our models get wet, and its waterproof, !😊
Mtroniks do have lipo friendly vipers, they are call "tio" I recall, if that is written on the cover you can set upo for lipo, if not then its imperative you have some sort of alarm as dave says, they plug into the balance lead on the lipo, and are current sensitive, so need to be the right way round to work. The ones I use are here, and also can be pre programmed to sound at a given low voltage. I use 3.7v on a boat, and 3.8v on a plane. Ant lower and they take longer to charge. If over discharged they are generally finished. There are ways to recover them, but its regarded as bad practise. Nims can be discharged fully, but are now really yesterdays technonlogy, heavier, and not any cheaper these days! https://hobbyking.com/en_us/ce ll-checker-with-low-voltage-al arm-2s-8s.html Paul
with my 4 foot fireboat, I use contra rotating props, from propshop. I was advised by them to have them turning outwards, as viewed from the rear, there was an explanation, I've forgotten it, however, on the water, at speed, turning was difficult, the boat just wanted to roll. I swopped them over, so turning inwards, and the handling was cured in an instance. Its easy enough to try one way, then the other, see what is best for you, but remember to use some sort of none permanent thread lock or you might lose one of your props
Hey Rob, I'm glad you mentioned the greenish hue, I have the same, and have always pondered over if it was correct. When I painted my 3 footer, in the BS 631 It had the green look, so when I did the 4 footer I used a different paint supplier, and it was the same. I wonder if over time the definition of the colour has changed? Coming along nice, its very time consuming isn't it! As you have 94, and I have 93, same boats but subtle differences as they were in real life, it would be very nice to get them together some day👍
First time in a while, it saw daylight, Ideal weather, bright, mild, and choppy water, and music sort of makes it look faster! No doubt thge internet police will jump in about this😱 https://www.youtube.com/watch? v=WT_7oGKMMBc
personally, I prefer the transmitter bleeps to programme, I'm probably the only person in the world that will say this! I have used these esc's a number of times, amp rating is over egged, as with all turnigy stuff, but I doubt that will worry you. Its just my opinion, but I would have normal/mid start, soft start is very soft and slow, but with the card it should be easy enough to test at the lake, and change to suit. Now you have brushless motors, its like using old 4 stroke fuel with a v12 Ferrari, time to go lipo!!😁 yippee!👍
As you all know, Stephen does a real nice selection of 3d printed fittings. I had a dilemma recently, and asked him if he could do a specific thing for me. After some time finding plans etc, and waiting for me to supply sizes, I got what I wanted! The Piper Cub plane has a specific engine, a Continental, with 4 cylinders protruding from the cowl, nobody does a nice scale model of this, they are usually just some bits of balsa and plastic stuck on the sides. Well I have nice ones now, Good eh! And just for good measure, the last picture is the real thing that I used for reference. There should be heat shields over the cylinders, but then you cant se them, so I'm leaving that off so all can admire what I have!😊