toto Posted January 14 Author Share Posted January 14 OK ..... how about this as suggested .... not yet strapped in permanently. Just for an idea of how it would fit really. As Grumpy says pretty irrelevant how it looks as long as it works and doesn't put the ESC at risk. and .... connection to the battery still doable and lead to the receiver needed a short extension added. I had been playing about with a air scoop that I started knocking up. made from thin brass sheet .... could be attached either to the fuselage top access hatch ..... or on the underside of the fuselage. I would add some louvre slats if I went with it. thats all for now toto Quote Link to comment Share on other sites More sharing options...
Philip Lewis 3 Posted January 14 Share Posted January 14 Perfectly good way to do it, no need to over think or over complicate it, it's in great cool airflow there. Quote Link to comment Share on other sites More sharing options...
toto Posted January 14 Author Share Posted January 14 What about the battery compartment. Toto Quote Link to comment Share on other sites More sharing options...
GrumpyGnome Posted January 14 Share Posted January 14 Cool air will come in through the hole in the firewall. Cut a hole in the film anywhere aft of the pack.... underneath is least obvious... Quote Link to comment Share on other sites More sharing options...
Philip Lewis 3 Posted January 14 Share Posted January 14 Batteries don't need cooling, in fact LiPo's perform best at about 35C. Anyway if you think about it you can only cool the two outside two cell packs the others are sandwiched in between the other cells so colling is non existent for those inner cells or at best minimal. BTW Toto (and anyone else interested), if you are really concerned about cooling the ESC then you can cut off the heatshrink, remove the metal cooling plate that is only held on by thermal paste and put a proper heatshrink on it, the type made for attachment to PCB boards, there are plenty available on e bay and you can buy them in oversize blocks and cut to size, best attached with thermal glue or else you'll need to use tie wraps or something else to hold them on. This really is not critical or even important on a model like this though which is hardly pushing things to any limits. 2 Quote Link to comment Share on other sites More sharing options...
Eric Robson Posted January 15 Share Posted January 15 One of our club members has his esc on the outside of the fuselage side with the wires going through holes into the battery and motor compartments, it is held on with double sided tape. I've never had problems with hot batteries despite not providing a lot of cooling flow, my Ju88 only has a hole for the motor leads to come through. The main thing is to not over load the battery or esc. 1 Quote Link to comment Share on other sites More sharing options...
Christopher Wolfe Posted January 15 Share Posted January 15 16 hours ago, toto said: So .... I turned my attention to the ESC itself .... looks pretty good on the face of it ...... I do use one of these deans to EC5 adaptors though .... Hmmmm .... but no signs of burning or arcing etc ..... we move on .... to some real surgery .... I cut off the heatshrink that covers the ESC .... prise of the cover and it looks ok this side ..... aaaaaaa .... what's this I see sneaking out from the bottom edge .... and stinking of a burning smell ..... The culprit I believe ..... better known as " toast " ..... and the underside of the cover that was on top if it .......so .... we now know where it is .... but .... what has caused it. The model complete with the ESC, Receiver, battery and motor was all previously tested using a Watt Meter to see what power and current were being drawn produced etc and all was well. I will need to rescue the original figures data from the Domino post in order to demonstrate. Meanwhile ...... I must do something to bring the Domino back into service. I have no less than 3 more of these Overlander 60A ESC's in stock ..... so it looks like another one goes into service. I also have a Beatles 60A ESC that I could use but the motor connections and battery connections would need to be ordered in to be able to use that. I actually want to go with an other Overlander as I want to see if this would happen for a third time. I will post up with my reinstallation and also look at opportunities to move the ESC to a less crowded and better ventillated position just for the sake of good practice as I don't think the ventillation had any part to play in this instance. I'll be back. toto Dear toto. The soldered joints on the connecting wires is abysmal (VBATT, GND and the 3 motor wires). Unlike the SMD components which were presumably machine placed and soldered the connecting wires appear to be hand soldered with pasty looking cold soldered blobs. No individual conductor wires are visible and there are traces of flux residue between the wires (although these might be remains of the FET's) To me this indicated a lack of Q/C. Next time spend a few more quid for something of better quality, it's probably cheaper than a new arf. * Chris * Quote Link to comment Share on other sites More sharing options...
David Davis Posted January 15 Share Posted January 15 Can't help thinking that you'd have saved all this trouble and expense if you'd fitted a decent two-stroke to the model. 😏 2 1 1 Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted January 15 Share Posted January 15 5 minutes ago, David Davis said: Can't help thinking that you'd have saved all this trouble and expense if you'd fitted a decent two-stroke to the model. 😏 Then you clearly haven't been following Toto's other thread, documenting the problems that he was having with his two-stroke equipped trainer that barely got off the ground before suffering several in flight engine stoppages. 2 Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted January 15 Share Posted January 15 25 minutes ago, Christopher Wolfe said: Next time spend a few more quid for something of better quality Sorry but that doesn’t guarantee anything or even reduce the risk. I’ve had ‘expensive’ ESCs which have failed and I’ve had cheap ones that have failed. Funnily enough I recently bought several unbranded ones from AliExpress, 30a ones for the princely sum of £6 each. They’ve all proved to be totally reliable! Likewise the HobbyKing YEP and Redbrick ones have given me excellent service over the years. I just think that Toto has been unlucky. 4 Quote Link to comment Share on other sites More sharing options...
Nigel R Posted January 15 Share Posted January 15 Overlander use rebadged Hobbywing don't they? Last I checked they were generally ok. I would stick the ESC out in the breeze for now. Simple, effective - this is a trainer, not a concourse d'elegance winner. If you want to use the scoop (which looks very neat) I'd use it as an air exit, just behind the lipo and on the underside of the fuselage. That would then draw air, and very effectively too, through the model - over all the electronics. 1 Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted January 15 Share Posted January 15 I must have 20+ Hobbywing ESCs that, so far, have performed flawlessly with no issues and no extraordinary efforts to ensure maximum cooling. I think it's interesting to note the earlier comments about there potentially being a "bad batch" of ESCs and Christopher's observation regarding some oth the agricultural soldering in Toto's pictures. Quote Link to comment Share on other sites More sharing options...
Engine Doctor Posted January 15 Share Posted January 15 ESC's must be made in the millions and are only batch tested. Its just potc uck really who get the duff ones. Ive just fitted out a small model installing a new ,from a sealed pack, 30 amp ESC . This was eratic at test stage at starting the motor 7sing my servo tester instead of a reciever and within a few seconds let the magic smoke out. After testing the resistance of the motor i decided to try another ESC and success . Leaving an ESC laying loosly on top of the battery though is sloppy instalation and bad practice. Fit it firmly some where with cooling air flow pasding over it . Anything that can move about can alter cg and the moving wires can be a failure point. Good luck with the new setup. Quote Link to comment Share on other sites More sharing options...
PatMc Posted January 15 Share Posted January 15 12 minutes ago, Engine Doctor said: ...After testing the resistance of the motor i decided to try another ESC and success . ... How did you test the resistance of the motor, what type of meter did you use & roughly what was the resistance ? Quote Link to comment Share on other sites More sharing options...
David Davis Posted January 15 Share Posted January 15 1 hour ago, leccyflyer said: Then you clearly haven't been following Toto's other thread, documenting the problems that he was having with his two-stroke equipped trainer that barely got off the ground before suffering several in flight engine stoppages. As a matter of fact I have been following his other thread. It would appear that there was nobody at his first club who knew how to tune a simple two-stroke engine. A sign of the times I guess. 3 Quote Link to comment Share on other sites More sharing options...
Christopher Wolfe Posted January 15 Share Posted January 15 43 minutes ago, leccyflyer said: I must have 20+ Hobbywing ESCs that, so far, have performed flawlessly with no issues and no extraordinary efforts to ensure maximum cooling. I think it's interesting to note the earlier comments about there potentially being a "bad batch" of ESCs and Christopher's observation regarding some oth the agricultural soldering in Toto's pictures. I did my training according to this standard NASA Soldering requirements and have worked in the industry for a few years or two so I might be a bit picky. The photos that toto provided indeed may from this 'bad batch' as the wires do not even have a meniscus to the PCB pads and are just 'Blobs'. As I said, a decent Q/C inspector would have identified these defects - but that costs $$$ * Chris * 1 Quote Link to comment Share on other sites More sharing options...
Geoff S Posted January 15 Share Posted January 15 16 minutes ago, PatMc said: How did you test the resistance of the motor, what type of meter did you use & roughly what was the resistance ? It's a mostly pointless test. One s/c turn on the motor will render it inoperative without affecting its DC resistance shown on any multimeter. The only useful resistance check is for a complete open circuit. 1 Quote Link to comment Share on other sites More sharing options...
leccyflyer Posted January 15 Share Posted January 15 13 minutes ago, David Davis said: As a matter of fact I have been following his other thread. It would appear that there was nobody at his first club who knew how to tune a simple two-stroke engine. A sign of the times I guess. That's progress 😉 2 Quote Link to comment Share on other sites More sharing options...
Rich Griff Posted January 15 Share Posted January 15 Thanks leccy, time will tell, mark 2 versions of the spit and 109, see shop adverts etc ... Toto, as GG says put the esc "in the wind"..... Quote Link to comment Share on other sites More sharing options...
Cuban8 Posted January 15 Share Posted January 15 I'm doubtful that overheating of the ESC is the route cause. It's not being driven to within an inch of its life even at full wallop according to watt meter figures, and I doubt if Toto is using sustained full throttle that often during a typical training sortie. I have come across an overheating ESC some years ago when a mate was puzzled as to why his quite high performance model's motor would 'hunt' and slow down after a few minutes of high speed flight. We determined after a few further flights that this was the ESC's way of indicating it was too hot and going into a self protection mode. We sorted the issue (badly selected prop/motor/ESC combination on what was a second hand model IIRC) and we reused the ESC with no further problems. I've never come across this sort of thing again, so the problem has to be very bad to show up. I'd have though that if Toto's ESC was getting too hot it would also have some means of giving a warning rather than just frying itself. Even a cheapo fan heater for the shed will have a thermal cutout, so I'd be very surprised indeed if most ESCs didn't have a way of shutting themselves down. Having had some experience in my work days repairing power supplies and the like, temperature figures are usually quoted for guidance but as far as I've seen are never given for our ESCs. One thing's for sure.....if the external temperature of a device is feeling very hot to the touch, then at the internal semiconductor junction itself where all the hard work is done, it'll be VERY hot indeed and this is accounted for in device specifications, heat sink sizes, air flow etc. Poor Toto, I've never known anyone have so much rough luck and agro.......... Quote Link to comment Share on other sites More sharing options...
David Davis Posted January 15 Share Posted January 15 46 minutes ago, leccyflyer said: That's progress 😉 It's change. Whether it's progress is a matter of opinion. 1 Quote Link to comment Share on other sites More sharing options...
PatMc Posted January 15 Share Posted January 15 41 minutes ago, Geoff S said: It's a mostly pointless test. One s/c turn on the motor will render it inoperative without affecting its DC resistance shown on any multimeter. The only useful resistance check is for a complete open circuit. Yes, I know, just curious if ED does. 😉 Even an open circuit result would require at least 2 of the windings to be OC unless the motor was delta wound, which would be unusual with our motors. Quote Link to comment Share on other sites More sharing options...
kc Posted January 15 Share Posted January 15 20 minutes ago, Cuban8 said: It's not being driven to within an inch of its life even at full wallop according to watt meter figures, and I doubt if Toto is using sustained full throttle that often during a typical training sortie Surely the ESC would get hotter during a training flight often on low throttle than on a full throttle flight? Doesn't it work harder when on partial throttle than on full throttle? Switches on and off more often for partial throttle. Or is my info wrong? If weight is not an issue then fit a Rx 'nicad' instead of using the BEC output. Then an ESC failure will not affect Rx controlling the model. Needs a switch harness and remembering to switch off after flight and recharge nicad of course. Quote Link to comment Share on other sites More sharing options...
GrumpyGnome Posted January 15 Share Posted January 15 We pretty much agreed the white smoke was not caused by overheating, a while back. Toto is just following best practice to not have it jammed in a compartment with the LiPo. 1 Quote Link to comment Share on other sites More sharing options...
Andy Stephenson Posted January 15 Share Posted January 15 I recently had a rare problem with a speed controller in an Aerobax Pirana. Testing it on the bench with the prop off, all was well until I plugged in the battery for another test, it made all the usual start-up tones then no throttle response, nothing else had been changed from when it ran. No smell of burning or any sign of overheating. I made all sorts of elimination tests on it but no joy. I sent it back to the supplier so we'll see what happens. Quote Link to comment Share on other sites More sharing options...
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