Ace Posted October 9, 2021 Share Posted October 9, 2021 Gorgeous - ? Quote Link to comment Share on other sites More sharing options...
Tim Flyer Posted October 9, 2021 Share Posted October 9, 2021 Superb model with great performance . I really enjoyed watching it! Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted October 10, 2021 Share Posted October 10, 2021 Very nice Jon, I’m jealous! Quote Link to comment Share on other sites More sharing options...
Engine Doctor Posted October 10, 2021 Share Posted October 10, 2021 ? Excellent ! Quote Link to comment Share on other sites More sharing options...
Nick A Posted October 10, 2021 Share Posted October 10, 2021 Superb ? Quote Link to comment Share on other sites More sharing options...
Engine Doctor Posted October 10, 2021 Share Posted October 10, 2021 John just a couple of questions re the Hurricane. Did you set CG as per plan ? What elevator throws did you use ? E.D. Quote Link to comment Share on other sites More sharing options...
Jon H Posted October 10, 2021 Author Share Posted October 10, 2021 7 hours ago, Engine Doctor said: John just a couple of questions re the Hurricane. Did you set CG as per plan ? What elevator throws did you use ? E.D. I have to confess, i havent a clue on both counts. When it came to c/g i suspended it from a crossbar in the fuselage that seemed about in the right place. At that point it needed nearly 2lbs of lead to balance so i knocked up 2lbs of lead and just went with that. Exactly where the c/g is i have no idea, but it felt fine when i picked it up so i ran with it. On the rates, i looked at the recommended throw and thought...nah, thats too much. So again i just guessed and my low rate choice was about spot on although i didnt measure it and have no idea what it actually is. I have set a new high rate though as i run out of elevator on low during takeoff and landing, but its only a few % more than the current low rate as the elevator is very sensitive. I suspect the model is slightly nose heavy, but as it is just perfect in the air and i am absolutely unable to stall it in its current configuration i will leave it alone, at least for now. I always stall test all of my models on maiden flights and with gear and flaps down i really had to work at it to coax a wing drop out of it. Even so, letting go of the sticks prevented a spin so it was all very reassuring. I am told that at least one club member has already added a Hurricane kit and spinner to his shopping cart so it clearly made an impression. Quote Link to comment Share on other sites More sharing options...
Engine Doctor Posted October 10, 2021 Share Posted October 10, 2021 Thanks John. Reason I asked was that I built a DB Hurricane for a mate who insisted he could fly it on the sticks with too much elevator movement with cg as per plan . Result was disaster. All repaired now and ready to rock and roll but I will tell him to dial down the elevator movement. Quote Link to comment Share on other sites More sharing options...
Jon H Posted October 11, 2021 Author Share Posted October 11, 2021 If you like i can measure the travel? The elevator is very sensitive as in all warbirds and i found this on the first takeoff. I trimmed slightly nose down for the maiden as the last thing i want is for it to leap into the air before i want it to. I selected my high rate, no idea what it was but less than the recommended 35mm im sure, and set off. Once the tail was up my down trim tried to nose it over so i gave a tug on the stick to prevent it. That put the tail down again and there was a fair bit of wagging up/down while i sorted out how much pull i needed. In the air, gear up, rates low immediately and this got things calmed down. As the speed came up my down trim was not a million miles wide of the mark but needed adjustment. As i trimmed up though my trimmer ran away a bit and the pitch up was significant even with only 3 or 4 beeps of surplus trim. As for stalling, mine wont. With gear and flap up i simply cant stall it even with the nose pointing way up and the thing wallowing around like a hippo. With gear and flaps down it will stall but its nowhere near as vicious as my La7 or Sea Fury. I tried a stupidly tight low ish speed turn as well and it was very civilised. Quote Link to comment Share on other sites More sharing options...
Jon H Posted October 11, 2021 Author Share Posted October 11, 2021 Got sent this by a clubmate. For some reason the video quality isnt brilliant but its all we have for now! 6 1 Quote Link to comment Share on other sites More sharing options...
Ron Gray Posted October 11, 2021 Share Posted October 11, 2021 Still jealous but even more so now. Quote Link to comment Share on other sites More sharing options...
Jon H Posted October 11, 2021 Author Share Posted October 11, 2021 (edited) 47 minutes ago, Ron Gray said: Still jealous but even more so now. Sounds like DB might have a run on Hurricane kits at this rate ? I mean, you already have the engine.... Edited October 11, 2021 by Jon - Laser Engines 1 Quote Link to comment Share on other sites More sharing options...
John Stainforth Posted October 11, 2021 Share Posted October 11, 2021 8 hours ago, Jon - Laser Engines said: Sounds like DB might have a run on Hurricane kits at this rate ? I mean, you already have the engine.... So Laser might have run on their engines and need to up their production! 2 Quote Link to comment Share on other sites More sharing options...
Jon H Posted October 11, 2021 Author Share Posted October 11, 2021 4 hours ago, John Stainforth said: So Laser might have run on their engines and need to up their production! if only i had the parts Quote Link to comment Share on other sites More sharing options...
Jon H Posted October 19, 2021 Author Share Posted October 19, 2021 (edited) Just a quick update on repairs following the first flights. A new u/c door has been made and is being painted, the engine bolts have all been refitted with loctite after i removed a layer of lead from the nose weight. The undercarriage legs had their rotation issues fixed by grinding flats on them as mr schoolboy error forgot first time round. The dummy exhausts on the cowl have been hollowed for a little extra cooling, trim tape fitted round the dummy wingtip lights, belly radiator removed and refitted with better glue, elevator servo installed more securely after the mount failed at one end, and i have hooked up and fitted the gubbins needed for the landing lights in the wings. A few random photos below. thats what 2lbs of lead looks like! One leaf removed for c/g adjustment. Low tech switch for lights. Every time i use an electronic switch the rest of the radio has a fit so its low tech city for me. I also had all the bits kicking around. Edited October 19, 2021 by Jon - Laser Engines Quote Link to comment Share on other sites More sharing options...
Nigel R Posted October 20, 2021 Share Posted October 20, 2021 ha, love the low tech switch ? Quote Link to comment Share on other sites More sharing options...
Jon H Posted October 20, 2021 Author Share Posted October 20, 2021 13 hours ago, Nigel R said: ha, love the low tech switch ? It didnt cost a penny ? As i mentioned before, i have had so many problems with electronic switches and other stuff connected to rx's that i dont touch them any more. Just recently i got a 2nd hand spacewalker with an electronic switch in it for controlling lights. While setting it up the radio kept going into meltdown to the point where moving the throttle servo moved the elevator! admittedly i was using an older 35mhz rx but it had a total freak out. The electronic swtich immediately went in the bin. Doing it this way i can also use a separate battery. This is handy as i can use a lower voltage on the lights to prolong their life, and it means a short on the lights will not short the rx battery. Quote Link to comment Share on other sites More sharing options...
Artto Ilmanen Posted February 16, 2023 Share Posted February 16, 2023 The model flies great Jon! Congrats! From what you wrote earlier I understand you flew the model with an 18X8 on the video. since that you have experimented different props to get more vertical performance and less speed as far as I understand. How did it turn out, were the other props better in vertical performance? Quote Link to comment Share on other sites More sharing options...
Jon H Posted February 16, 2023 Author Share Posted February 16, 2023 I have been experimenting with props but in truth its just a feel thing. I cant quantify it, the model just didnt feel as nice on some props and felt great on others. Quote Link to comment Share on other sites More sharing options...
Artto Ilmanen Posted February 16, 2023 Share Posted February 16, 2023 7 minutes ago, Jon - Laser Engines said: I have been experimenting with props but in truth its just a feel thing. I cant quantify it, the model just didnt feel as nice on some props and felt great on others. Thanks Jon, I see.. in anyways, this is promising with respect to my YA Spitty as both DB Hurricane and YA Spitfire are more or less equal aerodynamically, both beeing quite a good ones, I guess Quote Link to comment Share on other sites More sharing options...
Andy Stephenson Posted February 17, 2023 Share Posted February 17, 2023 Jon, if you need that much lead you haven't used a big enough engine, but seriously though those securing nuts will eat into the soft lead and it will come loose very quickly, ask me how I know. Some large washers would help there. Quote Link to comment Share on other sites More sharing options...
Jon H Posted February 17, 2023 Author Share Posted February 17, 2023 2 minutes ago, Andy Stephenson said: Jon, if you need that much lead you haven't used a big enough engine, but seriously though those securing nuts will eat into the soft lead and it will come loose very quickly, ask me how I know. Some large washers would help there. The engine is a 240v, i couldnt use larger without it hanging out of the cowl. Not that it would make much difference as a 300v is not much heavier and the model is more than adequately powered with the 240v anyway. As has been discussed, i am trying to finds ways of slowing it down rather than speeding it up! Also 2lbs of lead is pretty standard for a warbird and nothing to worry about. Again its my 10% rule. As long as the lead carried is no more than 10% of the flying weight of the model its all good. The 'bigger engine less lead' argument is...dare i say daft? Lead is cheaper than engines, bigger engines use more fuel even when throttled back, if you have enough power for the given weight of the model adding more power and removing lead does nothing to improve performance assuming you fly at the same speed you did before. The added power will just make the model faster and this is not what i want. I guess i could make the engine from steel and not ali, that would work! As for the lead, i have not had any trouble in the past when i have used this method. My smaller Hurricane is what, 6 years old? something like that. Its not been a problem on there although i use captive nuts hammered into the lead on that one. although it has not flown many hours the DB is showing no signs of it being an issue here either. Given its youth it is regularly inspected for this exact reason and so far, all is well. Quote Link to comment Share on other sites More sharing options...
Chris Walby Posted February 17, 2023 Share Posted February 17, 2023 The 'bigger engine less lead' argument is...well more problems Bigger engine on same prop as smaller engine going to rev its nuts off - little or no chance of ever getting that through a noise test, the answer is to prop it up if you have the clearence. Possibly need to over prop it which is not good. And another thing is you will end up flying around at low throttle settings which will probably result in a less reliable engine as it goes cold in flight and dead sticks on you..the alternative is scream around the sky like a pylon racer. Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted February 17, 2023 Share Posted February 17, 2023 There is no Black or White answer, mostly just different opinions, you have to balance, sometimes lead is the way to go, other times a heavier motor solves the issue not that big a deal. Flying at low throttle ? well I've yet to read a Laser owner who flys over 1/4 throttle. Quote Link to comment Share on other sites More sharing options...
Jon H Posted February 17, 2023 Author Share Posted February 17, 2023 45 minutes ago, john stones 1 - Moderator said: There is no Black or White answer, mostly just different opinions, you have to balance, sometimes lead is the way to go, other times a heavier motor solves the issue not that big a deal. Flying at low throttle ? well I've yet to read a Laser owner who flys over 1/4 throttle. I should do a video showing my throttle use when flying my sea fury. On occasion im sure i nearly break my throttle stick off the tx 😉 As a friend of mine once opined, thrash it to within an inch of its life...and then another 5/8 Quote Link to comment Share on other sites More sharing options...
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