Ron Gray Posted January 30, 2019 Share Posted January 30, 2019 5645 are notorious for high current draw, I do use them but am wary about 'over use' in any one 'plane having had this pointed out to me! Quote Link to comment Share on other sites More sharing options...
Nigel R Posted January 30, 2019 Share Posted January 30, 2019 Are they any more juicy than any other 11kg/cm type digital, though? Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted January 30, 2019 Share Posted January 30, 2019 I think that the 5645s are in the top sector of high current draw ones, other makes offering same torque seem to be better (and I am an avid Hitec user!). Quote Link to comment Share on other sites More sharing options...
Jonathan M Posted January 31, 2019 Author Share Posted January 31, 2019 UPDATE: Lost control yesterday of my IC Acrowot in almost identical circumstances. Model failed to respond to centralising the sticks after three spin turns. It did finally wake up, after another two or three turns, but by this point it was just too late to prevent controlling it away from its destructive meeting with the ground. The engine and servos are re-usable, but the airframe was totalled. As I'd already decided to move over to FrSky Taranis for my glider stuff (for other reasons), I've now decided to also migrate (what's left of) my power stuff over as well. The Taranis X9D Plus which I've ordered comes with the 868mHz plug-in module and antenna. This is intended (as I understand it) for transmissions over longer distances - so if there is a component of dirty airwaves from the mobile-phone mast 500m away, then this might make some difference? Not blaming, just rationalising... Other observations: The 4.8v 2000mAh Eneloop NiMh had only half an hour's use on it since a full recycling charge the day before, and the temperature was about 4-5°. The servos are Futaba S3003 which were perfect for the model and never gave me any grief. I cannot rule out my own incompetency or lack of piloting skills (I'm an intermediate not an expert). After the death of the Wot4 last week, I should really perhaps carried out a full six-axis range-test of the Acrowot on the ground first, but I've had it for two years - and had never previously had any control issues, including coming out from spins immediately without needing opposite rudder. Maybe there was/is something dicky with the TX? But I have no idea how to test for this, and have already decided to move on. I won't be replacing the Acrowot with another one or anything similar in the near future, just focus on the new Wot4 for the time being (the retailer has, by the way, given me a credit for the old New Power servos). The next IC model I want to build is the Gangster 63 Lite kit (for an OS 35AX). Maybe in the fullness of time I'll find something else (a kit or a plan) that's just right for the 70FS...? Jon Quote Link to comment Share on other sites More sharing options...
Nigel R Posted January 31, 2019 Share Posted January 31, 2019 Nightmare! With my investigative head on - Do I understand right, that you did not range check at all before flying? And was that also the case with the Wot 4? Other common factors - TX Location of incident - a particular place within the site? Time of day? Chris Foss design? (sorry, just trying to inject a bit of humour) It is possible something has gone south in the TX RF output stages, or the aerial is broken, leading to reduced range. You can get 2.4GHz tester widgets - I have one. Gives a simple LED indication of the power output. Probably not very useful if lots of TXs are switched on, but if you're by yourself it can show that all's well (or not). Quote Link to comment Share on other sites More sharing options...
Jonathan M Posted January 31, 2019 Author Share Posted January 31, 2019 I did in fact range-check as I always do before flying, both the W4 last week and the AW yesterday - but only the normal walking 30-35m away from static model in one direction (reduced-power signal normally fails at about 35m). A fuller check would have been from 30m away from all four main aspects (front, tail, and from each of the wings) plus from above and below, a total of 6 axes, so to speak. Who ever does that? Re position on the flying site, last week I was circuiting the SW-NE runway and yesterday the NW-SE one, so where I first positioned to enter the spin was different on each occasion, but only by a lateral margin of maybe 200m or so. There indeed might be an issue with the consistency of the TX RF output, or the aerial? A while ago, doing basic model checks on the ground I thought there was a momentary freeze, but put it down to my imagination - your mentioning this end of things has only now just prompted my memory! Edited By Jonathan M on 31/01/2019 16:35:40 Quote Link to comment Share on other sites More sharing options...
Paul Marsh Posted January 31, 2019 Share Posted January 31, 2019 Bit of a bad luck, losing two models like that. The only thing must the transmitter and obviously you don't want to use that anymore! Really, I thought that you would've taken a more caution to the transmitter as the previous crash was still unexplained and the tx was/is a suspect. Quote Link to comment Share on other sites More sharing options...
Stephen Smith 14 Posted January 31, 2019 Share Posted January 31, 2019 Hate to say told you so, but told you so. See my post sixth down on first page. Wonder how long it will be before people realise. Edited By Stephen Smith 14 on 31/01/2019 18:56:08 Edited By Stephen Smith 14 on 31/01/2019 18:56:45 Quote Link to comment Share on other sites More sharing options...
Peter Beeney Posted January 31, 2019 Share Posted January 31, 2019 Jon, Very sorry indeed to read about your Acrowot, I’ve always though it’s bad enough when I plant one due to my own mistake but when it’s due to an unknown factor… I would very much suspect that changing over completely to FrSky will eliminate this, I’m sure they do occasionally malfunction but there seems to be few reports of this. Assuming you’ve spun the Acrowot before with no ill effects, then now the common factor must be the transmitter. I suspect you won’t be using this any more so it probably doesn’t matter too much. Having spent much time over many years in the past tinkering about with model aeroplanes trying to get all things flying to actually fail, and not really having a lot of success, as it happens, I tend to discount much of the obvious stuff in the first instance and try to find something a little more obscure; but at the same time I’d still be thinking that if I do get a glitch and I don’t make every every effort to sort it it will eventually come back to haunt me… All the very best of luck with the Taranis, a complete tx at a good price, as with all the necessary other bits and pieces to go with it. I’m sure you will enjoy this… …but I like the Horus although I haven’t got one…yet! Just for interest, for some years we’ve always done a full power range check at 700 metres point to point. I’ve related previously in other posts our procedure on this, but so far we’ve never had a failure. At a push we could probably get another 200 metres but as we consider a normal sized model is disappearing fast anyway at 700m, 2,300ft, it’s seems rather a moot point. This is ground range too, air range is said to increase by up to 10 times. I believe telephone signal transmitting masts are tested regularly for the transmitted signal strength; this is to make sure it’s none hazardous; that’s for the effect it might have on people. I think this is done quite close to the mast so I would would also tend to discount this as well. Happy landings… PB Quote Link to comment Share on other sites More sharing options...
Geoff S Posted January 31, 2019 Share Posted January 31, 2019 That's really sad, Jonathon. You must be somewhat gutted. As a very experienced modeller once said to me a good few years back "It's a hard game." I suppose it didn't help that there seems to have been 2 faults with the Wot4 incident and the motor not responding to the throttle stick a couple of times disguised the probable transmitter failure and they were treated as part of the same thing. You're right as regards range checking. For a brand new model (especially one I've built) I walk all round it range checking before the maiden but if I'n checking an established model I do as you did - and then not every time, just when it's not been flown for a while. Geoff Quote Link to comment Share on other sites More sharing options...
Bruce Collinson Posted January 31, 2019 Share Posted January 31, 2019 Meant to say re the LiPo, my first ... or was it the second? Mrs. Watt 4 (must nave been of the female persuasion, seemed to have a mind of its own) had an arrival hard enough to Bugnerise the LiPo which was promptly quarantined against a minor thermonuclear eruption. After I got bored with that, I cycled it very warily, then charged it fully, then taped it up like a prop forward’s ears and use it regularly two years later. I think its the wing off that one that is about to emerge from the hangar post repair. Bummer to lose the AW too. I find it difficult to pick between the two for the first flight of the day but do find the AW more satisfying. Both electric, both with the U/c mods alluded to, reinforced plate, larger wheels (sheep on strip), absolutely nylon bolts, catastrophic cig lighter and crappy screwdriver always to hand in case the stubs stick. Still unsettled by Spektrum but about two thirds of the serious regular pilots at my club use it and I’m very tempted by Yeti but it’s awful dear. BTC Quote Link to comment Share on other sites More sharing options...
PETER BRUCE - Eastchurch Gap Posted January 31, 2019 Share Posted January 31, 2019 Hi all. Don’t know if this could help but l lost my AcrowotXL a while back and I was always looking for the reason... Quote Link to comment Share on other sites More sharing options...
Nigel R Posted January 31, 2019 Share Posted January 31, 2019 "Hate to say told you so, but told you so. See my post sixth down on first page. Wonder how long it will be before people realise" You on Hitecs payroll? Plenty folk use Spektrum with zero problems attributable to it. Quote Link to comment Share on other sites More sharing options...
Jonathan M Posted February 1, 2019 Author Share Posted February 1, 2019 Posted by Paul Marsh on 31/01/2019 17:53:16: Bit of a bad luck, losing two models like that. The only thing must the transmitter and obviously you don't want to use that anymore! Really, I thought that you would've taken a more caution to the transmitter as the previous crash was still unexplained and the tx was/is a suspect. Paul, I can't argue with that. What I can say is that both losses happening so short a time (only ever wrote-off one model previously, that due to basic pilot error when over-confidence got the better of me shortly after passing my A) have now forced me to revise my whole approach to RC - that every electronic, electric, connecting, motive and moving part, and especially the understanding and decisions of the human being on the ground, are critical to safe and successful flying. Quote Link to comment Share on other sites More sharing options...
Jonathan M Posted February 1, 2019 Author Share Posted February 1, 2019 A valuable video Peter, not directly connected with either of my recent mishaps, but - as I've just noted above - a crucial element in the complete set of connections. What switch type do you now use? Quote Link to comment Share on other sites More sharing options...
Nigel R Posted February 1, 2019 Share Posted February 1, 2019 "every electronic, electric, connecting, motive and moving part, and especially the understanding and decisions of the human being on the ground, are critical to safe and successful flying" Ain't that the truth - chain, weakest link, etc. And sometimes, even despite our best efforts, something goes awry. All we can do, is check what we can, do our best to ensure it all works (including the human on the sticks). Take a moment to think how much effort goes into making the real ones safe! Quote Link to comment Share on other sites More sharing options...
PETER BRUCE - Eastchurch Gap Posted February 1, 2019 Share Posted February 1, 2019 Hi Jonathan. I’m now on my third AcrowotXL which is taking shape in the shed now that the diesel heater is installed and it’s toasty. All my planes to date have been mostly sedate First World War biplanes and the AcrowotXL was my first venture into a good acrobatic model and the learning curve has been interesting to date - although frustrating as well. Sometimes we get a crash and something doesn’t add up and that’s what I had on my last model. As a result I am now trying a power box which perhaps is overkill but at least with this if the switch fails it defaults to on... When I get my AcrowotXL finished I’m going to replace all the batteries (as I usually do ) and this time all the slide switches in my other models will be changed over to good old toggle switches with a good old clunk function. After having the last issue on the Acro I thought of how an old engine feels when you get it out of a draw which it’s been in for a few years - go to turn it over and it’s all stiff an if you delve further everything seems coated inside with a varnish. An engine I stripped down a few years back was so bad just put it in the dishwasher (not the bearings) which worked great but the wife was first in the dishwasher so you can guess her words of wisdom to me on that score... Anyway I digress - it occurred to me that the slide switches a lot of us use are not sealed so the oil we get splattering out of the exhaust must find its way into the switch and end up coating the conducting slider and contacts making a good insulator and a bad contact. This would be especially true with glo fuel and as allmost all my biplanes are four stroke glo engines this is now the reason I’m changing the switches at the same time I change my batteries. Many who read this will say you should always do it but be fair - when you go to the field how many members change over the slide switches every year... OK there will be the ones who do but most don’t. Our hobby is now very involved indeed compared to the modeller of the sixties as although the latter more probably had better building skills today’s builder has to be a good plumber, electrician, electronics engineer, computer aware, health and safety aware and Uncle Tom cobbley and all. Couupled with this we still have a radio link to our planes - which is much more reliable than my 27 MHz system I had in the sixties but still far from infallible... Sorry for the rant. Regards Peter Quote Link to comment Share on other sites More sharing options...
Nigel R Posted February 1, 2019 Share Posted February 1, 2019 Switches are mechanical beasts, as such are ideally protected from vibration and oil. The best method I've seen (although I will be the first to admit I've been guilty of short-cutting this in the past) is * mount the switch (in the normal way) to a ply plate * mount the ply plate like a servo on rubber grommets, internally, in the fuselage * the switch is actuated using a short pushrod extending through fuselage side. edit: those powerbox widgets achieve a lot of this by using a remote switch, and the actual switch is a "fail-on" relay of some description, plus the powerbox can be grommet mouted, or stuck in with squashy servo tape, or similar Edited By Nigel R on 01/02/2019 11:25:49 Quote Link to comment Share on other sites More sharing options...
Masher Posted February 1, 2019 Share Posted February 1, 2019 "Switches are mechanical beasts, as such are ideally protected from vibration and oil." It depends! Check your switch and be careful where they are sourced. Here is one as supplied, look closely. Also note these switches were originally intended for PCB mounting in early transistor radio's. There resilience to 'our' conditions is questionable. Quote Link to comment Share on other sites More sharing options...
Jonathan M Posted February 1, 2019 Author Share Posted February 1, 2019 We had a similar discussion on another thread a while ago, but to continue it again here: would something like this toggle-switch be more reliable - or is it overkill in terms of spec and size (61x14x24mm) for and average sports aerobatic like an Acrowot or Gangster 63 Lite? And what is a "fuel dot"? Jon A solid billet of aircraft aluminium alloy is CNC machined to produce the pinnacle of RC power switches. Designed to handle 8.4v these LiPo compatible switches also feature premium military specification toggle switches and are designed to operate under the harshest conditions without breaking into a sweat. They feature heavy duty silicon cable and are finely soldered and crimped to ensure rugged and trouble free operation. ET0770-3 and 4 also feature the addition of an integrated fuel dot with nitrile O-ring will suit petrol and glow fuel. Quote Link to comment Share on other sites More sharing options...
Nigel R Posted February 1, 2019 Share Posted February 1, 2019 Fuel dot is just something neat and tidy to fill you tank through. Cheap and cheerful = bung in the 3rd fuel ('filler' line to tank, waving around by the engine. Fancy = fuel dot on the end of same line. Quote Link to comment Share on other sites More sharing options...
Jonathan M Posted February 1, 2019 Author Share Posted February 1, 2019 Posted by Nigel R on 01/02/2019 11:59:45: Fuel dot is just something neat and tidy to fill you tank through. Cheap and cheerful = bung in the 3rd fuel ( 'filler' ) line to tank, waving around by the engine. Just what I do... er... did! Quote Link to comment Share on other sites More sharing options...
Gordon Tarling Posted February 1, 2019 Share Posted February 1, 2019 Jonathan - Do yourself a big favour and replace any 4 cell Eneloop Rx pack with a 5 cell one. It's been well proven that Eneloop cells have a high internal resistance and are unable to deliver the required current without a large voltage sag. Using 5 cells helps to get around the problem, though I'd prefer to use other types of cell myself. Quote Link to comment Share on other sites More sharing options...
Jonathan M Posted February 1, 2019 Author Share Posted February 1, 2019 That's very wise advice Gordon. What "other types of cell" would one consider? Quote Link to comment Share on other sites More sharing options...
Nigel R Posted February 1, 2019 Share Posted February 1, 2019 " It's been well proven that Eneloop cells have a high internal resistance" From memory, manufacturer data on internal resistance suggests they do not. Do you have a link to any testing done on Eneloops that disproves the manufacture information? The original nimh cells were quite high internal resistance but the newer low discharge cells are much improved. Quote Link to comment Share on other sites More sharing options...
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