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glypo

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Everything posted by glypo

  1. Yup, but that's basically looping the loop. F1 cars though, probably have more than enough force to drive on a ceiling.
  2. You are spot on about the S, not sure why I made such a bad error. Looks like I essentially joined two sentences together. But yes the reference area applies for the wing, and rest of the sentence is fine. Trust me you don't use cross sectional area for a wing for reference! Typically you can use planform area, as I suggest in my post (use wing span and wing chord) or if you can be bothered use a wetted area. It is essential you keep reference lengths the same though for all the calculations, or you need to non-dimensionalise all your values when transferring between calculations. And no, we have not quoted the equation, for the very reasons mentioned above. For a non-lifting body such as a fuselage, or a car body, people typically use frontal cross-section. Thus if you look for empirical cl/cd's, as I assume was done in this case, you need to keep reference the same hence by point. However a lifting surface you always tend to look at planform or wetted area, thus empirical data will also be based on this, thus you need to use the standard lift equation I stated above. As for ISA, there is a reason in aerodynamics we use it. There is no such thing as standard! Simply assuming ISA at sea level makes life infinitely easier. ISA was set based on North American and European averages so it's as good as it gets for an average day. Hence everyone else uses it, and if you pull from dimensionalised empirical data you can almost be assured for race-car that ISA was set at sea level, thus non-dimensionalise, transfer to the rc car and then dimensionalise again but with the new values. As for CFD being complicated, it really depends on methods. Sure you can run an Euler, Reynolds-Averages Navier-Stokes..... and they take hours or days even on the big cluster machines at work. However the basic methods I stated don't require griding or computation, just plug in some numbers and get a result. It won't be totally accurate, but it's not as if an aircraft is being certified. Being in the ball-park I imagine would be fine. As for wings being used in RC, I have never seen a proper wing being used in RC so your argument about NACA sections falls over there anyway. If it was me, I wouldn't even use an aerofoil and just do flat plate theory, much easier. Typically you get spoilers on RC cars, so if this guy is trying to work out aerodynamics of a spoiler he is wasting his time using the lift equation. However judging by the fact he has gone to some effort, and done quite well minus a few mistakes, I assume he would be using a custom/special wing of some kind.
  3. I can't really figure out your maths to be honest. W*H*A is total rubbish I feel. As are basically most the comments above by everyone (sorry, but it's true). How on earth can there by any generic factor where you can multiple a scalar in this manner with the wing alpha. The basic lift equation, and one that should always be used is: L = 0.5 * rho * (v^2) * cl * s So your S is reference length, typically you can use wing chord or span, just ensure the reference stays the same. Rho is density at ground level. You are kind of right, but again kind of wrong on this. Just pick the value for sea level from the ISA, this is 1.225kg/m^3. Cl is the lift coefficient of the wing. Simple as that. Also make sure velocity is also in SI units (m/s). This is how you work out the wing. To be honest I have no idea how you worked out your Cl's before without any kind of computational fluid dynamics. If I was you I would just chuck your wing geomety in a basic Kutta Joukowski solver, or one of panel methods that has the NACA 4xxx aerofoils already built in for basic wing design and analysis.
  4. I'm sorry, but how? It's a two stroke engine, showing the two stroke cycle?
  5. You PM inbox is full! If it's not already gone I'll take the M18, Thanks
  6. Well all the racers have moved away from the TT because of their speed around the track. Advertise it on sites with bashers as that will be your best market and give you much more money.
  7. Didn't have to be Spud you got it off did it? If so enjoy my old Mugen Ace/Thunder tiger servos are good for the money as said above. KO and Futaba are always good too. Nija's simply haven't been around long enough for anyone too tell you how good they really are. They are doing OK in the races but so far not outstanding. The Euros later this month and of course the Worlds following not long after will but good tests of them. Novarossi is a bit of a dark area as well at the momemnt. Having lost nearly all of their team drivers, a new untested engine range (821 etc) and hard to ge hold of, might not be a brilliant choice. RB's new engines are great though and would seem like a safe bet for racing. They certainly hold their own in any condition, including this weekends mega heat.
  8. Pretty good?? The best is closer to the mark! Just check ou JH on top of the nationals with one...
  9. Nitro Models is the best place for RB's, they import them after all. The C6 will be much much more more then your 728. The WS7-III is a better choice, as they are fast and quick acceleration, but the power is smooth so it's not as hard on your transmission.
  10. RcK review on it. I got a go when I was doing the photos/video for the review, not bad at all. http://rckingdom.co.uk/mam/index.php?optio...=179&Itemid=138
  11. glypo

    2wd drive MT

    Real 2wd monster trucks, like the Havoc, are much faster then equivalent 4wd because there is only a third of the gearboxes/diffs then that of the 4wd, and no big shafts etc. Getting to get a 4wd to run well as a 2wd there are quite a few setup changes that need to be done to get the best from them.
  12. That sums it up in my eyes. Petrols can't do the big jumps, hence to the comment above there is no big jumps. They are too heavy and rip up the track on landing. There is already enough holes at the Nook as is. They do race buggies and trucks, I just think the track is too bumpy for them. Trucks will be better then buggies with their bigger tyres though. If it's rallycross racing you are after try Pendle, after all they did hold the Euros not too many years back and it's still a good facility for decent buggy racing.
  13. Kevs new site is a lot better then the old though. It's a shame as I missed out on setting him up with a real top notch site. Glad you got an email back. As others have said Kev is a top bloke and should sort you out.
  14. I've been racing the RRCi Rallycross Buggies. The Nook at wakefield was the first track in the series. I agree with what you have read, petrol only. Check the video out here: http://glypo.co.uk/rrci/wakefield.php Dez Chand is the editor of RRCi magazine and a very skilled driver indeed. You can see just how much work he had to put in to get it around the track. For less experinced drivers it is fustrating. The bumps are too great for rallycross buggies in my eyes. There are some good tracks up north though, perhaps have a look at Pendle, at a guess about an hours drive from Leeds?
  15. Well PM sent and fingers crossed.
  16. Any chance of a reply to my PM? Thanks
  17. Yep, they've changed to just 'Mega' now rather then 'NovaMega' since the NR to Picco switch. They still have their range of MF modified engines, and MF is a good. I use MF own brand (MaxPower/NovaMax/Max) engines in rallycross and they are simply insane. Either way I don’t think this engine will disappoint in the F1. If it does I’ll just replace anyway.
  18. Obviously not a nitro on-road fan then? Serpent use NovaMega engines, like that one. The Evo 4 and 5 are considered among the fastest engines of all time. The Evo 5 could hit over 50,000 revs, making it possibly the fastest revving two stroke engine in existence. TNT mods, RB mods etc come nothing close to the Mega Evo factory engines. Not sure what this one is like, but sure it can't be that bad considering their heritage. Eitherway, contacted Elite and hopefully will get mine pre-ordered very soon.
  19. Perfect addition to my tricked out Tamiya F1. I need to get mine pre-ordered I suppsoe, I'll phone up elite this week
  20. Last time we had awesome fun We launched things into outer space, had helicopters floating about, FG's, savages, buggies, even lorries & more! We are doing all this again on Good Friday yes that's right, 21st April 2006 This is the same location as last time, which is Oakley, near Basignstoke down here in southern England. It will be a small one though this time, very last minute and lots of 3 day races on that weekend, so dont expect many people to be there. I'll have my Havoc and Crono at least, there will be a micro nitro buggy, the new huge engine t-maxx and a few more things More details can be found here: http://www.rckingdom.co.uk/mam/index.php?o...g19159#msg19159 We would really love to meet up with some of you MSUK guys again, just like last time
  21. For the Havoc, once again you have the pipe on a vertical incline. Madmaxx is right, but that is a later stage. Firstly you have to do a little thinking. Imagine the manifold is full of fuel/liquid. You need to poor it out the exhuast. So firstly you tilt the Havoc on the side so the fuel flows to the back of the manifold, then you tilt it backwards to the fuel now flows into the back of the manifold, then tilt it to the other side so the fuel flows into the pipe, then backwards again to get it out of the pipe. If that sounds complicated, it's easy really. The only difficult thing is not being able to see the fuel, so you have to imagine where it is. Once you have cleared the manifold of fuel, then take the glowplug off and do as said above. Just turn the engine over with a cloth on the head. Please note be very carefully. Nitro fuel can, and will blind you. Cover the head up carefully! The real trick with the engine though, is not flooding it. The Havoc only takes a short time to prime as the pipe from tank to carb is very very small. You'll soon pick up the pefect priming technique and wont have any issues. Have fun
  22. Dazzi is right, your engine was flooded. The Havocs manifold runs a vertical incline, the engine would have eventually hydro-locked and your e-start sheared (Schumacher do say to use a torque limiter on your drill!). If you want some advice, find the minimum torque setting that will turn the engine over. If the engine doesn't turn over at that setting, you know there is a problem. What happened with you is the engine became locked, and you unleashed the full power of the drill of the e-start, which can't turn over the engine as it is locked. Something had to give way, you were luck it wasn't your drill. Thunder Tiger engines are the most reliable out there. I can say that happily owning 6 nitro cars at the moment, and having owned 28 nitro engines in my RC history. TT engines always start the easiest, hold their tune the best and last the longest. (My TT .21 took over 15 gallons and still wanted to go for more, until I cut it in half to demonstrate how engines work) Dazzi regarding your 3 engines, really not sure how. I admit that Schumacher trucks of the past were not upto the quality of some others, but the engines are spot on. As for those worried about the quality, when I wrote the review I meant every word of it. It is LIGHTYEARS ahead of previous Schumacher trucks. In fact my Savage is being split up to sell on eBay now I have a Havoc, shows how much I think of it!
  23. What you didn't see in the video was the out takes. All the jumps that went wrong and it still kept on going. Trust me this thing is strong. I have/had a Menace and the Havoc is a completely different league. I don’t know how it looks weaker the a Menace?!?! 10mm + wishbones, 4.75mm thick balls in the diff! The transmission is tougher then any other truck, including the Savage, MGT and so on, just so much tougher. This is now Menace, it literally is a different class.
  24. Easy to break? Providing it is meshed correctly there really is nothing to worry about. We certainly haven't had any problems so far. So nothing to worry about
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