MattyB
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Posts posted by MattyB
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2 hours ago, Paul De Tourtoulon said:
Did they just dive into the ground from less than 20 metres for no reason like the two I witnessed ?.
I thought that it might be a Tx ariel orientation problem, do they do range checks ?.
Models that dive straight into the ground are not indicative of a signal loss. Remember, if the RX is still powered, it should go to failsafe which - unless it is set for something crazy, like full down - should not result in an instant steep dive. The issue you describe is far more likely to be an onboard power failure, or something none RF based like a bound up control or servo failure. The way to tell for sure is look at the telemetry log, if a telemetry RX was fitted. If not full power testing of that RX pack/BEC needs to be carried out before it is used again.
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48 minutes ago, Tosh McCaber said:
Part 2
It's been flying really well, since it's been trimmed out. However, on launching, it really needs a good 45 deg throw by the person who's chucking it, to avoid an initial contact with the grass! He has to have a really good strong arm!
The structure would take it, (see my initial photo at the top of the thread) so I'm considering upgrading the motor a bit from the 2212 10T 1400kv with a 7x4 prop, to a 28?? -????kv motor. Next motor family up. Now, unfortunately, I'm pretty useless at filling in the question mark spaces for the specs. I'd be obliged if any of you motor gurus out there can help? Along with prop size (preferably 8" max due to the prop clearance on the wing and fin?)
Here's the range of motors that I am looking at from Ali Express- free 7 day delivery:
Any suggestions/ discussion welcomed!
There is a whole forum dedicated to this with specialist threads on motors, ESCs, prop choices and wattmeters - worth a read...
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32 minutes ago, PatMc said:
There is no absolute max power for a motor, however there is a max current it can take. Since power is the product of voltage & current the max power can only be stated with reference to the voltage that is being supplied.
Fair point, I should have stated "The max power a given combination of these factors will generate is NOT the same as the maximum current the motor can sustain!"
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More nasty news today regarding global temperature trends - worldwide average temperatures in September have broken all previous records, and by some margin...
https://www.bbc.co.uk/news/science-environment-67017021
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28 minutes ago, Learner said:
That probably wouldnt be the case with an accident damaged car, thats why the insurance could be more expensive.
The insurance issues with EVs were discussed a few pages ago at great length, inclduing this very issue of repairs. Putting that aside though, since when was fixing accident damage considered maintenance? Here is the original post from Erfolg...
2 hours ago, Erfolg said:....On the other hand I have read that a significant proportion of EVs maintenance bills, is the H&S issue of isolating/discharging the batteries.
...and the relevent section of my response....
1 hour ago, MattyB said:...In this case I'm still calling FUD, as whilst high voltage electrics are obviously very dangerous if incorrectly handled, 99% of garage visits will not require them to go anywhere near them. Take a look at Tesla's maintenance schedule page if you don't believe me - there are no tasks that require a mech to go anywhere near the powertrain.
Anyway, this conversation is going round in circles again. Since it's clear the sceptics/anti-EVers in this thread will just continue posting their half-remembered Daily Mail "facts" ad-infinitum without any critical analysis of the sources, it's time to admit defeat and duck out. Whatever you drive, enjoy it, but please maintain a healthy scepticism of whatever you read in the press or social media on this topic - anybody vehemently on one side of this argument or the other should be questioned as to what their motives are for sitting on one of the extremes.
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Indeed. They are certainly not a company I'd be looking to invest in!
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Lots of good posts above explaining some of the technical detail, but for those who prefer simple rules of thumb...
- The motor Kv, prop and input voltage (which is directly influenced by the internal resistance of the pack) are the primary factors in determining how much current is pulled and power is generated at full throttle. However...
- The max power a given combination of these factors will generate is NOT the same as the maximum power the motor can sustain!
- To determine that for the a typical low end brushless motor in a standard tractor sport model, take the mass of the motor in grams, multiply x3* - the figure you have is a conservative estimate of the maximum power in Watts the motor can safely sustain.
- Carrying a bigger motor and running it at less it's maximum peak sustained power has no real negatives in a practical sense other than the additional noseweight (whcih in many cases will be useful). Doing the opposite (i.e. running a motor that is too small beyond it's max sustained peak power capability) definitely does!
* - For higher end motor and in other types of models (e.g. EDFs) where cooling is very good, this multiplier can be increased safely, but stick with 3 until you have sufficient expereince to know when you can push the envelope safely.
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17 minutes ago, Erfolg said:
I know very little, other than what has been written with respect to working with EVs. The amount of energy in many domestic type devices, are very low, respective to energy in a car EV battery.
Compare a domestic light switch when being actuated, with a National Grid switch. In your home arcing is not a big issue, on the grid, their are typical SF6. oil, air, breakers.
From what is written removing EV batteries is a potentially big deal safety issue (as can be working on a EV).
As usual Erfolg, no source. If you want these half remembered anecdotes to be more credible, you need to link us to the source so we can decide the for ourselves. In this case I'm still calling FUD, as whilst high voltage electrics are obviously very dangerous if incorrectly handled, 99% of garage visits will not require them to go anywerhe near them. Take a look at Tesla's maintenance schedule page if you don't believe me - there are no tasks that require a mech to go anywhere near the powertrain.
For further clarification on batt swapping see above; I've added detail added to my post via an edit. The video shows you how this is done by Nio - a swap takes 5 min and is zero human touch. The car even reverses itself into the bay for the change!
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1 hour ago, Erfolg said:
MatyB, any charging must be at a cost to the user. This must apply to wireless charging.
I don't think anyone is expecting charging to be free, wireless or not! My comments were merely based on it being a potential practical soolution to charging issues in certain use cases.
1 hour ago, Erfolg said:Swapping batteries, seems great at first sight. As you have written, not a practical solution. It interests me how it is possible to physically switch a battery, I know it is happening from what you have written.
Just watch the video above, they demonstrate it starting from 4m16s. To be fair it is very impressive tech, I just don't think it scales well and requires a level of cooperation between manufacturrers that is incredibly unlikely.
1 hour ago, Erfolg said:On the other hand I have read that a significant proportion of EVs maintenance bills, is the H&S issue of isolating/discharging the batteries.
Sorry, don't know where you read that, but it's more FUD. If you have to replace the battery in a car then yes, obviously the mechanics will need to carry out specific procedures to do so given the high voltages involved, but there is zero need to do that for regular maintenance/servicing (which in an EV basically contitutes checking the brakes, tyres and wipers, topping up the washer fluid and sending you on your way).
29 minutes ago, Paul De Tourtoulon said:What's wrong with swapping battery's the only fixed one I have is in my phone, my tv channel changer, radio, torch, cordless drill etc,,, all have batteries that are swapped.
I listed all the reasons in my post above. Battery switching makes sense in applications where the pack is cheap, small, light and not a structural element of the device. EV batteries fail those criteria on all points!
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16 hours ago, Geoff S said:
(Battery swapping) does seem to be a more viable option than so-called fast charging which needs very high power sources to supply the necessary energy quicker. It will mean a standardisation of battery format, though, which will take some agreement amongst manufacturers.
16 hours ago, IDD15 said:NIO battery swapping and wireless EV charging.
Fully Charged - NIO Battery swap and EV Wireless charging
It’s gone very quiet on the wireless charging front since this episode of FC, though Tesla have bought a company that was developing it. I think there are now 26 NIO swapping stations in Scandinavia/Northern Europe and they just commissioned a newer version that does not jack up the car. The NIO vehicles can still fast charge in the conventional sense as well as battery swap.
I'm afraid this whole battery swap thing looks like cloud cuckoo stuff to me. Taking this approach requires massive collaboration/cooperation on the side of the manufacturers (yeah, right!), adds huge amounts of complexity, infrastructure, space for the swap stations and battery storage, not to mention the cost of all those. The system will also add weight to the car and restrict manufacturers in terms of the platforms and layouts they can use.
The fact that Nio have been doing this since 2014 but are still the only manufacturer following this path would seem to indicate it's not a favoured option and has a lot of disadvantages. Yes there are still issues with fast charging to be solved, but think about it - those same issues still have to be sorted even if you are doing battery swapping (all swapped packs will need to be charged nearly immediately so they can be used for an upcoming swapout, as to be cost effective there can't be twice as many batteries as cars with 50% not in use at any given time).
Wireless charging though does look to be a good idea, at least for vehicles like buses and short range urban runabouts. I'm not sure it really helps that much when you go on a med/long journey though, especially if (as espoused by the guy in the FC video) your car has a pack half the size of that in a current longer range EV:
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PS - Your last post finally nudged me into ordering the motor/prop/ESC combo for my two models; they should arrive at the start of Nov. They had been in my Ali basket for about a month!
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15 hours ago, Simon Chaddock said:
When inside the cockpit the ESC was getting rather warm so it is now outside!
Just need the right weather to try again.
Yeah, that is one of the challenges with a conversion like this; without the moulded vent holes that are always added at the design stage for a purpose built foamie e-glider, the ESC is somewhat entombed. I was already thinking I will vent via the front and back of the canopy and mount the ESC "floating just underneath the underside of the canopy, but that may still not be enough.
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1 hour ago, Gary Manuel said:
BYD = Build Your Dreams. No idea what it means business wise.
41 minutes ago, Frank Skilbeck said:Basically the Chinese government is backing the production of EVs big time and supporting their manufacturers to dominate the world market. EU and US already looking if their companies are unfairly undercutting domestic manufacturers. Tesla sales falling due to manufacturing disruption as they revamped the Model 3, which is by far their biggest seller.
BYD are one of big Chinese EV makers who actually make more cars than Tesla nowadays. In China their EVs are properly affordable and are revolutionising the market, but by the time they get over to the EU, UK or US they mysteriously seem to get a whole lot more expensive. You can buy BYDs (the Atto and Dolphon) and Ora (Cat) here now, Nio I don't think are (they are quite interesting in that they operate a battery swapping service in China as an alternative to fast charging).
I haven't seen many for these Chinese brand EVs around yet though. I did register my interest initially when Ora first announced, but when I saw what has happened to secondhand EV prices it quickly became obvious that buying a new one was not a good idea as a private buyer, especially not a challenger brand with little to no dealer network.
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1 hour ago, john davidson 1 said:
Interesting vid on youtube tried to copy with no luck
Jay Leno Hauls Tesla Semi With Tesla Semi
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2 hours ago, Simon Chaddock said:
Sufficient power but after a couple of circuits it lost both power and control which resulted in a rather fast glide into the ground. The very squelchy ground meant a near 'dead stop' landing with the nose part buried in the mud. Of course the controls worked after the crash but the mud in the nose prevented a motor test. It did at least fly.
My guess it was the park fly rx that was to blame. it simply lost contact with the HobbyKing TX6i transmitte. I have had this problem before with other cheap receivers.
I note the true Spektrum DX6i is rather more secure with such receivers.
When the modest repairs are complete the Park Fly rx will be replaced by a 'full range' Lemon 6ch
Random question... why do "park flyer" receivers even exist these days? Frsky and many others make absolutely tiny full range RXs that aren't any more expensive than big brand park flyer ones, so why do manufacturers even bother?
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2 hours ago, Erfolg said:
As for the weight issues with EVs, it is very real, most IC SUVs , weigh the same as the majority of EVs, at the lower end. The concerns of Multi story car parks, increased road wear are not the figment of being Anti-EVs groups/individuals, they are real issues. Some of the resent EV SUVs have a weight that no one would have thought as credible a few years back.
What am I missing here? A sample of representative SUVs with differing powertrains (EV weights from here, ICE ones from amnufacturer websites and Autocar)...
- Skoda Enyaq 60kwh - 1965kg
- Skoda Enyaq 80kwh - 2075kg
- Tesla Model Y std range - 1984 kg
- Tesla Model Y std range - 2054 kg
- Nissan Ariya 63 kwh - 1980kg
- Nissan Ariya 87 kwh - 2530kg (what a porker!)
- BMW X5 diesel 2016 model (i.e, prior to mass market EVs) - 2070kg
- BMW X5 diesel, 2023 model - 2295kg
- Audi Q5 Diesel - 1850kg
- Audi Q7 diesel - 2150kg
And for balance, three 2023 family hatches...
- VW ID3 55kwh - 1772kg
- Nissan Leaf 40kwh - 1580kg
- VW Golf diesel - 1450kg
So yes, the average EV probably is a tad heavier than the average ICE car, though Tesla are clearly leaders in keeping that weight under control. The problem for roads and car parks though is not EVs; it's the fact people started to edge towards ginormous unaerodynamice SUVs about 15 years ago, and car makers have continued to fuel that trend and build sales of their Chelsea barges where profit margins are presumably fatter. How many unnecessary millions of tonnes of additional vehicle weight are now loafing about out roads as a result, costing their owners more to fuel and reducing pedestrian. motorbike and bicyle safety?
PS - Yes, I know about the ID.Buzz California debacle. I can only assume the designers of that had completely lost the plot and were dreaming about sunny summers days on Venice beach or something as they added accessory after accessory and the weight climbed ever higher...!
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Did you try turning it on just the rudder? I am trying to decide whether to go r/e/f or add ailerons to mine; mus supicion is it iwll need a bit more dihedral/polyhedral if I go that route....
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1 hour ago, Erfolg said:
Nothing at present is crystal clear to me, much of the claims with respect to EVs vehicles, is hype, the difficulties glossed over. Who should pay for the additional infrastructure seems to be ducked.
Nobody here is glossing over the current situation wrt the shorter range on one "tank" vs. ICE, longer time to recharge vs liquid fuels, or flakey public charging infrastructure. Every EV owner knows those are factors at present, but they are all steadily improving over time. What there is a lot of is people who have never driven or owned an EV telling people who have one or are considering one that they are rubbish because they don't yet fit everyone's use case. If that's the case for you then fine, don't buy one, no-one is making you (least of all Rishi it seems), but please don't moan at those of us who do want to move forward with EVs on the basis that they suit our needs just fine.
1 hour ago, Erfolg said:The additional damage to roads should be paid for by EVs, IMO the user should pay, not the carless old age pensioner, or other similar type of group.
This is just FUD. An EV does no more damage to the road than an ICE car of the same weight. It is weight we should be worried about, not powertrain.
Yes, an EV of the same size is 10-20% heavier than an equivalently sized ICE car, but is that really the dominant factor causing roads to deteriorate when there are only somewhere between 1-1.5m of them in the UK? Way before EVs were a thing people started moving to big, heavy SUVs, but weirdly nobody got worried about the impact to roads then or advocated for a tax based on weight. How many school Mums in Audi Q7s are there for every Leaf or Model 3 that replaced a Golf or BMW 3 series? And what about all the extra supermarket home delivery and parcel logistics lorries that trundle up and down rural and domestic roads because most of us (me included!) no longer shop in towns as much? The fourth power law says that the damage caused by those vehiles must absolutely dwarf anything you could put down to EVs.
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39 minutes ago, Erfolg said:
MattyB, I was quoting an article, with respect to proportional battery value. On reflection the concept that some manufacturers are loosing money on EVs, has been true, maybe still true. The question why would that happen, it seems in the case of the BMW i3 was a case in point. Then some have been producing EVs to achieve quotes. These sort of things do confuse the waters as to true costs of batteries, never mind manufacturing infrastructures, design costs.
OK, but if you are quoting an article, post the link, that way we can all read it and decide if it is plausible or not. There is so much FUD out there, just saying "I've read an article that says..." doesn't help us anyone understand whether or not it was based on facts and data or jsut made up guesswork.
Ultimately whether manufacturers have lost money on a given model of EV is not something that you can say is directly related to the % cost of the battery vs overall vehicle cost. The former (profit on a given model) is based on a myriad of factors (how mature the company is at making EVs, prod volumes, # markets car sold, where manufactured, shiipping costs etc.), whereas the latter (Li ion batt costs per kwh) is a single variable that is well understood - most EV manufacturers get their cells from a relatively small number of mass market specialists in the field, and there are reliable global metrics that track costs over time that are public knowledge.
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4 minutes ago, IDD15 said:
New V4(?) chargers have longer cables and contactless payment for cards as well. There's a new open hub at just off the M6 at Trentham got them.
All credit to Tesla, they do not hang about banging in chargers and growing the network. Could not believe they'd doubled the number of chargers at Rugby when we visited the other week. All in less than 2 years!
Indeed. It's easier for them in some respects because they don't have decades of ICE investment to try and milk dry, but even so, love em or hate em they are the most forward looking automotive brand at this point, and certainly one of the most valuable. They still make mistakes - I still don't believe the revised Model 3 will make it to production in Europe with no indicator stalks - but they have looked at cars in a new way and designed from the ground up to take every advantage they can from it being an EV. Legacy auto have generally gone the other way and sought to ease us in to EVs by making cars that are as close to the faimilar ICE models that we are used to in the past, just with a different powerplant. Right now it is looking like going more radical is paying off - just ask VW Group's accountants...
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10 hours ago, Zflyer said:
If its any conciliation I got done 37 in a 40, on a bloody dual carriageway, crazy. £80 speed awareness via Zoom. 56 years of clean licence. Will be asking if it has to be declared next time I insure, bearing in mind any excuse to bump up a premium.
1 hour ago, GrumpyGnome said:AFAIK, you have to declare it. My premium went up by about 10%.
Apparently you don’t have to proactively declare it, but if they ask explicitly you have to provide the details…“Do I need to tell my insurer that I've taken a speed awareness course?
Not unless they ask you. There’s inconsistency between insurers - some might ask if you’ve taken a speed awareness course, others might not.
If they ask, or you mention it, the insurer might increase your insurance price. If they ask, you have to tell them. Otherwise your insurance might be invalid.
But a speed awareness course isn’t a driving conviction, and according to The National Driver Offender Retraining Scheme (NDORS) it shouldn’t be treated as one.
According to NDORS, you only have to give your insurer the information it asks for. This is thanks to a rule change in 2013. Before this, you’d have to volunteer any information that could be relevant to your policy.
When you get a quote with Confused.com don't ask if you've taken a speed awareness course. We only ask about driving convictions.”
https://www.confused.com/car-insurance/guides/speed-awareness-courses
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3 hours ago, J D 8 said:
Drat and Double drat, got me a ticket for 35 in a thirty.
First motoring offence in fifty three years of driving/riding.[ still have just paper slip] What's more it was in my old Land Rover Ninety. Thought I would have been ok as had spotted the van and checked speedo. However tests with my daughters modern car following shows my speedo under reads by 4/5mph.
Have to do the speed awareness course, the fee/fine for which is one the highest in the country.
I do not often drive out of my home county these day's my most regular "long" trip is the 32miles to the club flying field.
Most annoying is having to drive to the next county to attend it, a round journey of 101 miles for me.
Those of us who live in the county of Pembrokeshire feel we are second class citizens having to travel for most services [medical]these days.
Could you not jsut do it online? My wife did hers that way, it's commonplace round here though they do ask a LOT of questions to make sure you haven't jsut nipped off for a coffee and left Zoom on!
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2 hours ago, Learner said:
I'm sure you have you an independent report to back that up.
Tesla have made more than 4m cars now, including nigh on half a million in Q2 2023 alone; only BYD can get close, but they do still make hybrids as well in China. Tesla know more about mass EV manufacturing than anyone else, and lead the world in battery tech and by using newtechnologies like giga-casting. All but the very earliest ones have are remotely managed and every parameter monitored, so the data pool they have is richer. The long ranges of all the cars and the supercharger network also means they have more high mileage drivers than any other EV manufacturer.
Given all that, if there was a major battery degradation problem, I think we'd know about it by now. Certainly of the 15 or so Tesla owners I know personally, not one has ever had a battery issue or mentioned battery degradation. I suspect that is the reaon you buy a Tesla - yes they are still expensive (though better than their exec competition), but the tech you get plus the supercharger network means range anxiety jsut doesn't exist int he same way it does for drivers of other makes.
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3 hours ago, Learner said:
Shame the price of the cars aren't coming down then.
They are, but not fast enough I agree. You are right that manufacturers are trying to make more profit from them by focussing on the bigger, more expensive models where margins are higher. Over time as volumes scale up costs should steadily decrease, but ICE has 100+ years of development and refinement in terms of cost effective manufacture, so it will take time. I suspect we are still 3-5 years away from true cost parity in terms of the sticker prices of comparable ICE cars and EVs, though at the high end Tesla in particular are putting legacy automakers like BMW, Merc et al under some serious cost pressure now.
3 hours ago, Erfolg said:The cost of the batteries was quoted as part of the article on repair costs of EV vehicles, resulting in as much as 100% higher insurance premiums when compared to comparable IC cars.
You are conflating two different statements here. The exact quote you made was "I have also read that half the value of a EV is the battery". That is demonstrably not true - a new Leaf today witha 39kwh battery costs jsut under £30k in the UK, but as per my previous post that pack costs Nissan £6-7k to produce. If the pack really cost £15k to make, they would be losing money on every one.
2 hours ago, Paul De Tourtoulon said:Just looked up the tesla 3, from 15.000€ to 23.000€ replacement Renault Zoe 10.000€ !
sorry but in french,,,https://www.presse-citron.net/voiture-electrique-combien-coute-le-remplacement-de-batterie/
Actually those battery replacement costs (note - not manufacturing costs!) look pretty well aligned with that $155/kwh costs from the Staististica figures above by the time you have factored in transporting it over, specialist labour to fit etc.. Calcs below based on 1 euro = 1.05 USD:- Model 3 Std range - 55 kwh, $285/kwh
- Model 3 Long range - 75 kwh. $307/kwh
- Zoe - GT Line 50 kwh = $200/kwh, prev version with 41 kwh = $250/kwh (I don't know to which version you were refering)
The fact that replacing a pack should the car get shunted costs more than what the manufacturer pays intially should come as no surprise, as there is a lot of complexity involved - they are often structural elements of the car (this is in part why Teslas are so expensive to insure), so there will be a lot of time in removing the old one and installing the new. In reality though degradation rates now are low enough that replacement due to natural and mileage related ageing won't be needed for 95% of drivers, especially given these cars have pretty long ranges from new anyway, so even with a bit of degradation they are still perfectly usable for the vast majority of journeys.
PS - It is rather amusing that you quoted that article to "prove the point" that my batt costs were off, but didn't read the other bits that didn't quite suit your narrative... 😉
3 hours ago, Erfolg said:I must admit how you can compare a IC to EV on cost, has me scratching my head, what do you actually class as comparable, but I got the message.
No, I agree with you (I'm not a zealot 😉 ). If you are a company car buyer an EV is a financial no-brainer, but if you are a private buyer buying a new car outright (not on a 3 year PCP) it is almost impossible to make the financial case by the time you have factored in higher insurance, installing a home charger, and the fact that (other than on Teslas ) the serviceing costs seem to be being artificially inflated by garages despite the lack of actual work needed. We will undoubtedly go pure EV for our next (runabout) car, but that is primarily because of the dip in secondhand EV prices and the fact our solar means it makes complete sense to go electric. Would I buy a new one? No way, but then I wouldn't buy a new ICE car either...
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Slope Wing yaw wobble
in In The Air
Posted · Edited by MattyB
The SAS Wildthing is not a true chevron - it has a lot less sweep, so it can utilise a central fin. A chevron (note - a chevron is not the same as a plank flying wing, which has very different aerodynamics) has a fair amount of sweep that is stabilised with washout, so is much better with tip fins. The problem here is their size and shape, not their overall location.
@PDB, If you want to learn more about optimising a chevron wing, search for threads by the Predator on RCGroups (example thread) - he was the originator of a series of mods for the model that over here we knew as the Irvine X-it, or the Windrider Bee elsewhere in the world. He was also one of the first people to expereiment with laminating film as a covering for foam models.