Bruce Collinson Posted May 24, 2022 Share Posted May 24, 2022 Not necessarily Jeff …. Quote Link to comment Share on other sites More sharing options...
Nigel R Posted May 25, 2022 Share Posted May 25, 2022 Like you dd I use standard size servos in this sort of thing. Hs311 would be ok. That said, I would use something a bit stronger on rudder. Hs485 or similar. Quote Link to comment Share on other sites More sharing options...
Stuart Z Posted July 29, 2022 Share Posted July 29, 2022 Hi Has anyone any experience of electric setup in a DSM / Marvic Joker 40? Originally thought OS55AX but was wondering about electric setup. No experience of electric. S Quote Link to comment Share on other sites More sharing options...
Jeffrey Cottrell 2 Posted July 29, 2022 Author Share Posted July 29, 2022 Hi Stuart Couple of thoughts for you. On the 4Max website (www.4-max.co.uk) you will find suggested set-ups for various models. Go through the list and find a model as close as possible to yours. 2 on the list look close. Mick Reeves Gangster 63 Lite or PB models Bullet. On the page there will be a list of suggested components for each. Bear in mind these are only suggestions. Granted George at 4Max has a lot of experience in these, so probably better than guesswork. Otherwise, find out what prop a 55AX would use at what rpm, and use something like Electricalc to design a system that produces the same results. Bear in mind that an electric power system will generally use a bigger prop turning slower, so any results from Electricalc would be guidelines only. Some time ago I bought a DSM Smart Move, very similar to the Joker, which I was thinking of going electric. Did some experimental set ups on Electricalc, and found a few that would do. Project went no further than that, but I have the details still on file. Yours if they're any help to you. Jeff Quote Link to comment Share on other sites More sharing options...
Stuart Z Posted July 30, 2022 Share Posted July 30, 2022 Thanks Jeff, The Joker 40 is a deceptive name having a wingspan of 59" (if I don't mess with it). Looking at the 4-Max site it's more the Sebring Katana in size and weight albeit the wings are foam and not built up. So it looks like an expensive 5S set up is required. Puzzling, the Moonglow is also similar in size and weight but the specs for that are very very different. Beginning to make the OS 55AX on a pipe more attractive, just not at some of the clubs I go to. I can't find "Electricalc" but maybe that would help? S Quote Link to comment Share on other sites More sharing options...
Jeffrey Cottrell 2 Posted July 30, 2022 Author Share Posted July 30, 2022 Hi Stuart, still a bit of a black art, isn't it? I think the 40 in Joker 40 refers to the engine size rather than the model size. Looked at the Sebart Katana (couldn't find Sebring) but that looks more like a 3d model than an aerobatic. Big, fine pitch prop gives it away. Must admit I wouldn't use 5s anyway. Difficult to find a use for it on any other model. Oddly enough I did have a 5s set up for my Smart Move, but that needed a 16 x 8 prop, which was far too big for the model. Also looked at the Moonglow. Aerobatic model, but designed in 1968, for low powered 61 size engines, which were all that were available back then. Better bet to stick with the Bullet or Gangster. Here's the address for Electricalc: https://www.ecalc.ch/motorcalc.php You have to register to use it, but it's free after that. Don't forget I still have the set ups for my Smart Move. Project stalled, so I never got to use them in practice, but the one I would have chosen uses a 4s pack with an 800Kv motor and 12 x 6 prop. Pretty much in keeping with the style of model. hope this helps Jeff Quote Link to comment Share on other sites More sharing options...
Bruce Collinson Posted July 30, 2022 Share Posted July 30, 2022 Stuart, A 6-S setup will cost more upfront but I suspect it will be far more flexible in the future as there are lots of F3A mid-size designs out there which run on it. I have a Pichler Supra-Fly, a Curare and a foam Olympus all running on the same 6S LiPos, as does a Truggy-thing for when the weather is too poor to fly. I agree with Jeff, 5S may be difficult to re-use. I haven't priced 5S LiPos but I bet the extra cost for 6S is marginal, especially in good quality ones, e.g. Optipower. BTC Quote Link to comment Share on other sites More sharing options...
Stuart Z Posted July 30, 2022 Share Posted July 30, 2022 Jeff, Bruce, Words of wisdom I think. Yes a 5S setup is expensive but the 6S not much more. Having looked at the Bullet and the Moonglow they both use 4S setups. I'll try that and if it lacks the necessary, I'll upgrade to 6S setup. The cowl will accommodate both as far as I can see. Thanks to you both for the advice. A black art indeed! S Jeff - Thanks for the link! Quote Link to comment Share on other sites More sharing options...
Jeffrey Cottrell 2 Posted July 30, 2022 Author Share Posted July 30, 2022 Hi Guys Bruce Agree with all you say. Although I only use 6s on my helicopters, it's a viable option for Stuart. Only snag I can see is finding the right Kv and prop size. Could you let me know what you use on yours? Stuart Sorry, black art time. Your idea of upgrading to 6s if necessary sounds good in theory, but won't work in practice. For a 4s pack and a useful prop size (12 x 6), a motor Kv around the 800 area would be needed. However if you then decide on 6s with the same motor you would need to drop the prop size drastically (10 x 5 max) to keep the current draw within limits. 10 x 5 would be far too small for your model. Other than that to go 6s you would need to fit a different motor with lower Kv (400 or so) which would mean a physically bigger motor, running very inefficiently. Decision on cell count needs to be made first. My thoughts anyway, would welcome Bruce's input. Jeff Quote Link to comment Share on other sites More sharing options...
Stuart Z Posted July 30, 2022 Share Posted July 30, 2022 Thanks Jeff I was thinking along the latter lines of swapping the motor along with the battery. Having looked at the motor sizes on 4-Max it will not be straight forward as I thought so it might be a case of going for the 4S and if it's lacking, well that's that. I would welcome Bruce's thoughts though as it looks like it's one or the other with no switch option if the 4S is not up to the job. There was me thinking electric would be simple and clean. Think I'd rather get oily. All seems so simple with IC! S Quote Link to comment Share on other sites More sharing options...
Jeffrey Cottrell 2 Posted July 30, 2022 Author Share Posted July 30, 2022 11 minutes ago, Stuart Z said: Thanks Jeff so it might be a case of going for the 4S and if it's lacking, well that's that. Not so, Stuart If you go with the 4s 800 Kv combination you could play with prop sizes if the 12 x 6 doesn't float your boat. Electricalc says you could go up to at least 13 x 7 before the magic smoke starts coming out. Certainly a lot cheaper than switching motor and battery, plus you could get a selection of props and change at the field. Jeff Quote Link to comment Share on other sites More sharing options...
Stuart Z Posted July 30, 2022 Share Posted July 30, 2022 Thanks Jeff That sounds fair enough then. I’ll look to the 4S then. At the moment I’m still battling with the kit. Probably the biggest challenge I’ve built so far with parts that look like they were designed for the 60 size and parts that need a lot of fettling. At the moment working on a tail plane that is 10mm thick to go into a 6mm slot. Aileron stock was actually TE stock. Hey ho, reminds me of the “good old days”. Bit of a shock for anyone used to 21st century ARTF! Thanks for all your help! S Quote Link to comment Share on other sites More sharing options...
Jeffrey Cottrell 2 Posted July 30, 2022 Author Share Posted July 30, 2022 With you on that Stuart. Recently bought a Smart Move kit that had been in storage for 22 years. Imagine what that's done to the wing veneer. Need a lot of work before it's even possible to start building. Long term project, methinks Jeff Quote Link to comment Share on other sites More sharing options...
Jeffrey Cottrell 2 Posted July 30, 2022 Author Share Posted July 30, 2022 Shhh, don't tell everyone. That's probably getting an Irvine 53 up front !!! Quote Link to comment Share on other sites More sharing options...
Stuart Z Posted July 30, 2022 Share Posted July 30, 2022 Probably a wise move - the Irvine motor is generally quite powerful for it’s size. I had a full size Joker (70”) with an Irvine 61 and a mini pipe. Was good and in the vertical ! The Joker 40 is having it’s 30th anniversary this year, I paid the princely sum of £47.95 for it. S Quote Link to comment Share on other sites More sharing options...
John Wagg Posted July 30, 2022 Share Posted July 30, 2022 This is currently hung-up in the shed. Last flown about 1994. Came as a kit with foam decks front and rear. Foam wings of course. Moulded cockpit and plastic cowl. There was no plan just good instructions which are signed by Dave Kerswell ? Mine has an SC62 for power with a standard silencer. Needs a bit of lead at the tail for balance. Instructions suggest .91 four strokes, .46 two stroke piped or standard .61... Flew it with my FF7, which I also still have. Trying to pluck up enough courage to give it a blast but need to swap out a couple of servos and the power switch for reliability and safety reasons. Quote Link to comment Share on other sites More sharing options...
Stuart Z Posted July 30, 2022 Share Posted July 30, 2022 John Good luck with it! The DSM and Marvic models were all good flyers and to be honest all looked very much the same albeit my Saphir had the angled wing tips. S Quote Link to comment Share on other sites More sharing options...
David Davis Posted July 30, 2022 Share Posted July 30, 2022 (edited) I've also got an Aerostar. Mine is destined for an OS SF 61 when it comes to the top of the pile. I had one in the past but crashed it on landing approach through inexperience. Lovely fliers. Edited July 30, 2022 by David Davis Quote Link to comment Share on other sites More sharing options...
finn.jonassen Posted February 4, 2023 Share Posted February 4, 2023 Hi I have a Dave Smith Exelsior 188, untuched in original box. Too big for me, of interest for somebody? Regards, Finn Quote Link to comment Share on other sites More sharing options...
Bruce Collinson Posted February 4, 2023 Share Posted February 4, 2023 Very. PM with details? Bruce. Quote Link to comment Share on other sites More sharing options...
Andy,popeye Posted October 15, 2023 Share Posted October 15, 2023 I used to work for Dave Smith building r c planes he now lives in strensall, that's if he's still alive. Andy, Popeye York Quote Link to comment Share on other sites More sharing options...
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