Mike Potter Posted January 29, 2007 Share Posted January 29, 2007 Hi, can anyone point me to books or articles on the calculations neccessary to choose compatible sets of Motor/ESC/battery. I've built a couple of kits using recommended units, but I would eventually like to convert IC scale kits (which seem more abundant and detailed)to electric. Quote Link to comment Share on other sites More sharing options...
Bladerunner Posted January 30, 2007 Share Posted January 30, 2007 See the "Brushed and Brushless Confusion" thread above this one. Quote Link to comment Share on other sites More sharing options...
David Drew 1 Posted June 15, 2016 Share Posted June 15, 2016 The prolog. Two years ago I sought dvice from the trade about replacing a speed 600 in a ripmax Spitfire. It did noy go well. The engine supplied Wasp 1000KV 400 Watt on a 13 X 8 prop seemed much to torquey and takeoffs were a blinder with me and anyone else who tried to fly the damned thing holdong full opposite aileron to try and keep an even keel. The only way down was cut the throttle and glide in. Does anyone else have experience in changing the motor for the aircraft and if so what worked? Quote Link to comment Share on other sites More sharing options...
Denis Watkins Posted June 15, 2016 Share Posted June 15, 2016 2 things boys, 4Max.co.UK have many electric setups/particular models on their site And With a torquey motor, try progressive throttle on take off, feeding throttle in as ground speed builds up So as not to wind the model over Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted June 15, 2016 Share Posted June 15, 2016 Posted by David Drew 1 on 15/06/2016 18:26:44: The prolog. Two years ago I sought dvice from the trade about replacing a speed 600 in a ripmax Spitfire. It did noy go well. The engine supplied Wasp 1000KV 400 Watt on a 13 X 8 prop seemed much to torquey and takeoffs were a blinder with me and anyone else who tried to fly the damned thing holdong full opposite aileron to try and keep an even keel. The only way down was cut the throttle and glide in. Does anyone else have experience in changing the motor for the aircraft and if so what worked? A 13x8 on a 1000kv motor??? Good God David who sold you that set up.....? Maybe on a 2S battery it might make some sense but that's all. On a 3S battery I suspect you would be pulling around 60A, maybe more.....it's a wonder nothing melted...what battery were you actually using? Quote Link to comment Share on other sites More sharing options...
PeterF Posted June 15, 2016 Share Posted June 15, 2016 My Ripmax Spitfire runs on a Wasp 3542 1000KV motor on 3S and I use a 12 x 6E APC prop pulling 32 Amps to give 360W at 8200rpm and as the plane in flying condition weighs less than 3lb, this gives me unlimited vertical performance. I hand launch this myself without any problems, and do not need full throttle for the launch. It originally flew on a speed 600 and 8 cell NiCad pack to let you know how old it is. Quote Link to comment Share on other sites More sharing options...
Delta Foxtrot Posted June 15, 2016 Share Posted June 15, 2016 The Gibbs guides are very good introductions to this area **LINK** Quote Link to comment Share on other sites More sharing options...
onetenor Posted June 16, 2016 Share Posted June 16, 2016 Some good info on Model Boats forum re leccy Quote Link to comment Share on other sites More sharing options...
Daithi O Buitigh Posted June 16, 2016 Share Posted June 16, 2016 I used to have an electric power train - it was called the 'Duchess of Atholl' from Hornby Flamin heck - somebody's selling one here but he wants 500 quid for it!!!!!! Quote Link to comment Share on other sites More sharing options...
Fredrum Posted June 16, 2016 Share Posted June 16, 2016 Hi Mike. I've found the webocalc free software very useful for this. Quote Link to comment Share on other sites More sharing options...
David Drew 1 Posted June 16, 2016 Share Posted June 16, 2016 Been advised to try a three bladed 12X7, the motor is a Wasp 3542 on 3S battery. Anyone using one succesfully? Tried the progressive take off but always ran out of runway, it was always blind it or bust. Must admit to having fastened wheels on the beastie.adding about 4.5 oz of weight, Cg is spot on Quote Link to comment Share on other sites More sharing options...
Trevor Crook Posted June 17, 2016 Share Posted June 17, 2016 David, a 12x7 3-blader still sounds like too much prop on your set-up. I'd be inclined to try an 11x7 2-blade. Do you have a wattmeter? If not, you should get one, they don't cost much and are invaluable in getting the right set-up. I would aim for a prop size that gives around 400W in that model, and I think, as PeterF says above, an 11x7 or 12x6 2-blader would be in the right parish with a 3s battery and 1000kV. Mike, you will soon accumulate experience to get your power train choice in the right ball-park, enabling fine tuning with a wattmeter. Aim for 100W per pound of model weight as a starting point, choose the motor and esc to be capable of at least 120% of you power need. Most of my models are 3s (use 900-1000kV motors) or 4s (700-800kV) Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted June 17, 2016 Share Posted June 17, 2016 I have an 11 x 7 on an 1100kv motor & that pulls just over 40A on 3S so a 10 x 6/7 or maybe an 11x6 would be as big as you could go IMHO.... & yes buy a wattmeter so you know what is going on.... Quote Link to comment Share on other sites More sharing options...
PeterF Posted June 17, 2016 Share Posted June 17, 2016 Posted by David Drew 1 on 16/06/2016 19:28:22: Been advised to try a three bladed 12X7, the motor is a Wasp 3542 on 3S battery. Anyone using one succesfully? Tried the progressive take off but always ran out of runway, it was always blind it or bust. Must admit to having fastened wheels on the beastie.adding about 4.5 oz of weight, Cg is spot on David, See my post copied from above My Ripmax Spitfire runs on a Wasp 3542 1000KV motor on 3S and I use a 12 x 6E APC prop pulling 32 Amps to give 360W at 8200rpm and as the plane in flying condition weighs less than 3lb, this gives me unlimited vertical performance. I hand launch this myself without any problems, and do not need full throttle for the launch. Edited By PeterF on 17/06/2016 22:29:05 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.