Piers Bowlan

Autotrader is full of used EVs so I think there is a pretty healthy second hand market. Some people don't need an excuse to buy a new car, a neighbour of mine said he changed his car every year simply because he got bored driving the same car! He seemed surprised I didn't, especially when I told him I usually held onto them until they fell apart. My Diesel LR Disco 3 was regularly serviced but the big end went after 112k miles, shattering the crankshaft. 😱 Yes I was expecting 150-200K miles too 😢 My current Disco Sport developed a very noisy timing chain after 50K and I was told that it was a known design fault with the 2016 'Ingenium' engine. Apparently the tensioners fail, usually resulting in the chain breaking and righting off the engine. At great expense I had the chain replaced and it now runs like a sewing machine after 85k miles - and counting. That is why I like EVs, they don't have a timing chain! 🤣 Your green 1955 LR will probably never die Martin. They don't make em like they used to.

Never mind ‘saving the planet’, bourgeoning population growth is probably the biggest threat with the strain on resources, loss of habitat and diversity too. EVs are not much help with that, never mind global warning. I simply find EVs nicer to drive than IC, even though I have a nice diesel car too, to tow my caravan/boat (EVs pretty rubbish at that). It is the quiet smoothness and linear acceleration I like. Single pedal driving is a revelation as far as I am concerned. I like the simple engineering of an electric motor rather than an engine and drive train with a couple of thousand parts. Yes, batteries have their limitations and idiosyncrasies, less range in the cold for instance. But remember if you charge overnight, each morning you will likely have a couple of hundred miles of range even in a ‘budget EV’ which is normally OK for most people. Average UK mileage is 7500/year or about 20miles a day. Yes, there are not enough public chargers but which came first, IC cars or their petrol stations? Same with EVs and public chargers. Also, there should have been huge government incentives for companies to open them but that is down to politics and priorities! Talk to the unconvinced about EVs and they will usually say they couldn’t possible afford a Tesla. Who said anything about buying a Tesla? You are spoilt for choice and most EVs are cheaper than a Tesla, apart from prestige brands like BMW, Audi, Merc or LR. As EVs become mainstream more small entry-level models will enter the marketplace. Then there is the expanding second hand market…

Fascinating stuff Simon. Box spar similar to the Jodel, ahead of its time indeed (torsionally very stiff).

Doh 🙄! Thanks Ron.

If no luck you can download the plan from Outerzone. https://outerzone.co.uk/search/results.asp?keyword=Peggy+Sue Email the file to a local printer or take it in on a memory stick. I think SLEC have the cutting files for the CNC parts.

Some people are put off building from a plan simply because they consider cutting out the parts a chore. I really enjoy this aspect of making my own ‘kit of parts’, especially with your designs Peter. In the main they involve simple shapes that are quick to make. Sarik and SLEC provide an excellent service and the accurate fit of the CNC parts speeds up the build too (usually!). Great for those cash rich and time poor.

I have a couple of OS Max 15s and have been tempted by the model before now. The only review on the Pegasus website used a couple of 15s but said it was very under-powered but then he was using the AP 15 ‘Yellowjacket’, a bored out AP 09, light but no powerhouse. Be very interesting to hear how yours flies Caveman. Looking good and should sound brilliant! 🤩

4Max recommend this motor for a 96in Telemaster on 6S and a 17x5 prop. I think the weight of a Telemaster is only about 7lbs though so a bit of a floater. It has a slightly smaller span too than your cub. You may find that your Cub is lighter than 14lbs Simon on just a 6s LiPo. However that motor will only provide about 1200W so you may find your model a little underpowered with it. I suspect you may need more cells with such a large heavy model. Personally I would give 4Max a phone and ask them what they would recommend. Even if you don't buy one of their motors at least they would point you in the right direction regarding the required spec.

Expensive way of fixing your model. I've read of $400 for a 4in wide roll - better stick to duct tape in that case. In a 'previous life' I used to stick speed tape to the LE of helicopter rotor blades. It was a right swine to remove the old stuff too (you will be pleased to hear).

I don’t know which quarter scale cub you have Simon but the World Models cub (104inch span) has a flying weight of 6.3kg and a 120 to 160 4 stroke is recommended. So about 14lbs in old money would need about 1400W (?) which could be provided by a 6s LiPo pulling 60A I suggest. The only thing is with a very low kv of only 200v, I tend to agree with Pat Max, the rpm would be low (<5000) and you might need a very large propeller indeed to achieve the target 1400W? Being a cub it would probably fly OK on less power than that in a scale like fashion. Simon, have you thought of chatting to George Worley of 4Max and see what motor he would recommend? Might be an interesting comparison to your motor.

EV batteries are manufactured to industrial standards unlike our LiPos. The Nissan Leaf battery is guaranteed for 100,000 miles and 8 years. I havn’t noticed any loss of range or performance since I bought it eighteen months ago from new. Have done 18,000 miles now.

No doubt you have seen Murat’s build blog Gary? https://forums.modelflying.co.uk/index.php?/topic/47740-cambrian-elan-100-build-with-a-brushless-motor/ He used a spring to retain the wings instead of rubber bands.

My July 2021 Leaf+ Tekna has a switch to switch the <20mph forward warning off. When reversing is quiet as a mouse with not a sound! Leaf;- well designed and built. Quick and relaxing to drive. Reliable and economical.

Ah ha! Thanks for that Ron, a very comprehensive answer 👍

Looking forward to the Junior Rival RCM&E plan, in the fullness of time Delks.

Beautiful work Ron, it will look and sound amazing. If I may ask a silly question, do you think the rear cylinder may get a little warm in there, or am I missing something (probably)?

It’s is amazing what will fly with modern EDFs. 👍 I wonder if some larger intakes might improve things further (cheater holes?).

I have been following this very interesting thread Martin. A silly question perhaps but what are you using to cut the round lightening holes you made in the ‘spine’ of the fuselarge?

Interesting that Frank said the rudder was more sensitive with less dihedral. Counter intuitive perhaps! Thanks for that Andy.

😬

Lead is also cheaper than a battery placed well forward, perhaps beneath the motor of a short nosed model (eg Sopwith Camel). But the lead won’t give you a longer flight time 🤣

To my simple way of thinking (!) you start with the weight and type of model. A glider might fly with 75W per lb, (sorry Paul!) a sport model 100w while something aerobatic 150W+. A pylon racer or EDF 200W? Then, how fast will it fly and how many cells will the battery have. As a generalisation a fun fly or indoor model needs a higher torque motor to turn a bigger prop, say about 900kv for a THREE CELL battery. A sport model maybe 1000kv to 1200kv. A pylon racer or hot liner 1500kv -2000kv. EDF 3500kv? However, as you increase the voltage (number of cells) you will need proportionally a lower Kv motor for the same rpm. Faster models generally need smaller, courser pitch props that turn at a higher rpm, which is why a higher kv is appropriate (less torque) for these models. To put flesh on all of this, a program like eCalc could be invaluable and save spending money on unsuitable motors. Alternatively phone George Worley at 4Max who will advise on a suitable motor for your model. Much simpler! All motors should have a spec. sheet giving the max continuous power (in Watts) the motor is rated for. As Shaun says it is logical to prop the motor to provide max continuous power but no more, which is where your Watt meter is so useful. That’s my 2p worth at any rate. Now I will sit back and prepare to be shot down in flames 🔥!

It is great that there are companies like iGul, SLEC and Sarik who will provide this kind of laser cutting service. Perhaps I am unusual (odd?) but I actually enjoy cutting out ribs, finding it quite therapeutic! On the other hand I am not so keen on covering or putting a finish on a model. Horses for courses I suppose.

I think the canopy is £15 from Vortex Vacforms. http://www.vortex-vacforms.co.uk/canopies.htm .

I have the plan for the Nigel Hawes Tucano and May 2003 RCM&E articles, if anyone is interested. Just PM me. If you bought the balsa, I don’t think it would cost anywhere near £130 but you would need to cut out all the parts yourself! …but there aren’t many 😊