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TIM Shaw

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  1. Hi Bill You don't mention what the model is - provided it has ailerons I agree with previous comments. However, should it just be rudder / elevator you will need a little dihedral.
  2. Thrust line is actually a very simple concept in toy aeroplanes, and is simply the line drawn the centre of the crankshaft down the length of the model in both horizontal and vertical sections. As such, you choose where it is going to be based on where you bolt your motor mount and any downthrust or sidethrust you want to include. It only starts to get complicated when you try to determine where it should be, compared to the drag centres. It may be possible in theory, but I wouldn't know where to start. So TLAR to start with, use that to fix your tank position. then downthrust, sidethrust and CG trimming once its up and flying.....
  3. Posted by Trevor on 03/10/2017 16:44:10: Thanks for the feedback. 3lb seemed an ambitious target Tim, then I looked back a page and noticed that in July you gave the weight as just under 4lb. Is 3lb a typo or has it been on a crash diet? Oops sorry my mistake, typo it was.
  4. Good Luck with it Trevor. Mine - albeit just under 3lbs has absolutely no bad habits at all, certainly no flickiness. It's back up and running again, well enough to get 3rd at the Huddersfield meet a few weeks ago. Build it as martin drew it and I'm sure you will love it. It does have a rather large elevator and I think it is worthwhile paying attention to the security of the wood and linkages. Mine now has ply spreader plates top and bottom for the horn, and if I were building another I would think about twin pushrods too. Sure you'll love it! Cheers Tim
  5. Posted by Tony Kenny on 23/09/2017 22:07:54: In wish case, I'll shape it on my baby's bum! Failing that, I'll use a fine grain emery for the finish. Come to think of it, I'll use this same method to make a new front end too which will save some fibre glass work, I'm assuming I can sand the plastic rough and it will take paint, or leave it smooth and use solar film? I'd be wary of film - you might find the heat you need to shrink the film on would distort your moulding. Strapping / combat tape would be OK though. Might be a bit brittle for the impact zone though?
  6. Yep, they were great fun models. IIRC, the foam wing had a symmetrical root of conventional section, transistioning to a flat plate at the tip. As anyone who has ever tried to cut a foam delta will tell you, its very difficult to use conventional root and tip sections as you get massive kerf issues where the wire is moving really slowly at the tip. I suspect these deltas were cut by using a template at the root and a flat guide at the tip, but moving the wire parallel to the LE, which doe s work well. All deltas tend to have benign stall characteristics, and the Crusader could be flown very slowly, nose high, indeed.
  7. I agree with Percy - that is a Challenger delta, available from the shows back in the late 80s/early 90s. Can't remember the name of the firm though. I had the bigger version, called the Crusader, which flew nicely on an Irvine 46, later replaced with an OS 46SF . I think a good 32 or 36 would make it a lot of fun, but I wouldn't be going much smaller as someone once told me there is nothing as depressing to fly as an underpowered delta. I believe they had no undercarriage, so it was hand launch and you need enough grunt to pull away cleanly or it all gets a bit too exciting.
  8. Looking good Nigel. Re covering - I hate covering. I filmed my little Challenger and my KF4 / 40, and was frequently heard to mutter "wish I'd glassed the b*&*^^^& thing" along the way. I have glassed my Bullet, and am really wishing I'd filmed it.... Straight edges on overlapping film joints are very difficult, I can usually get a decent cut with a new scalpel bade, and have had some success using a rotary wallpaper trimming knife too, but it all goes pear shaped when I try to iron it on, bits shrink and pull away etc etc, so i usually end up cheating and covering the join with auto trim tape..... Sticking the canopy on is another job I rarely do well.....
  9. I love the Acrowot, don't think there is a better sport model out there, so much so that I've built 5 so far and have an unstarted kit for my sixth. in the garage. I had a Magnum Pro 45 in my first one, and that needed a pipe to perform properly (about 1989 though - engines might have come on a bit...) Then I went for a 70 Surpass 4 stroke in my second and found that to be overweight and if not exactly under-powered, at least a little slow. OS61SF however was as near perfect as i think you'll get, had similarly good results with a Thunder Tiger Pro 61 too. Having said a ll that, suspect the ARTF is lighter than my kit builds, and I am a great believer in the OS55AX too, I think that would be plenty powerful enough and light as well. Its also a fair point that I like to fly in a "spirited" fashion, and our strip is on fairly high, exposed moorland, so I do like to be able to cut through the weather as well.
  10. Hi Geoff The type of aircraft Peter is talking about are designed to be neutrally stable, and when properly trimmed each individual control input should have no side effects at all. The downthrust angle set means that there is a small downward thrust vector which cancels out any tendency to climb with increased power.Tthey have symmetrical wing sections and fly exactly the same inverted as they do the right way up - except of course that down becomes up and up can get expensive.... I actually always do a dive test, power off at 45 degrees and hope it gently pulls out or maintains the angle, but I don't do it until I'm pretty sure it's somewhere near - tuck under can be a frightening thing. I think a more precise indication - for the types of model I fly - is the amount of down you need to hold straight and level inverted, I prefer to have none, but thats just me
  11. Hoping for at least 3 fellow members too, and we've been doing missionary work among other local clubs.. If anyone needs guiding in, my mobile is 07904018146. If the forecast holds and Big Tims sarnies are up to their usual standards, this should be a good do....
  12. I used to run SC 46s all the time - early ones. I always sealed the carb into the crankcase with epoxy, threw away the spring clip on the needle valve and fitted a short piece of fuel tubing over the needle / fitting. I ran 10 x 8 APC props, Duraglow 10% Nitro and Enya No 3 plugs and found them to be reliable and powerful. A club mate at the time was an Irvine fan, always used straight fuel and OS No 8 plugs and he had no problems either. Then it happened I bought an Irvine 46 on his recommendation, and he bought an SC 40 on mine. Neither of us had any success with these engines at all, I was doing a plug a flight and eventually we got so fed up we swapped - he got the Irvine, I got the SC. And all our problems went away. I think because Irvines liked the straight fuel and cold plug, SCs preferred a bit of Nitro and a hot plug. So I don't know if you have changed your fuel or plug rating, but I'd try reducing the prop size, 10% nitro and an Enya No3 plug.
  13. Hi Doug Didn't see the crash and am not exactly a member - keep meaning to join, but life keeps getting in the way. I had a Calypso many years ago, and I liked it, although Not as much as the Suprafly I bought it to replace. My old one resurfaced at our club recently and I was delighted to fly it again - Rossi 61 five port on a pipe. Nice. I'm hoping to be at the Nats on Sunday, negotiating for a big enough car, but if the damage is not too awkward I would be happy to take it off your hands. text to 07904018146 would work for me Cheers Tim
  14. Posted by Michael Little on 31/07/2017 13:30:03: By Sub Spar do you mean a tube to put across both wings to give strength during high speed manoeuvre? And i plan to Add a strip of wood for the dowels to strengthen them. I wanted to try avoiding adding glass and resin for the wings so i think i may try the doped Modelspan Tissue if its any lighter. Thanks for the advise! Hi Michael. The subspar I referred to is just that strip of wood to anchor the rear of the wing dowels to both skins, no need for any tubes.. If you really want to go old school, take the time to look the technique up. I would apply a light coat of sanding sealer first, rub it down with wet and dry, maybe give it another. Then a coat of full strength dope. Tissue has a grain, which needs to be applied spanwise, and a shiney side which should be away from the wood. Cut it to shape, wet it and wring it out. Lay it over your panel, and then brush 50 /50 thinned dope through it, smoothing it out as you go. Note that coloured tissue was available, which is the lightest way of adding colour. do one panel at a time abd build up subsequent coats as necessary until ready for painting. I'd be using a similar technique with nylon on the fuz, just to add a bit of strength to it.
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