Bob Cotsford Posted August 15, 2014 Share Posted August 15, 2014 I've just finished putting together a Crescent Bullet which I bought as a second-hand kit. What I missed at the time is that the instructions should have been included on a CD but weren't, which is not really a problem as it's a pretty simple structure. One thing that would be useful though would be the balance point. As it stands mine weighs 4lb 7oz and balances 3 3/4" back from the root leading edge. It looks like it might be a bit far back, with an 11" root chord that comes out about 34% Does anyone remember what the safe limits are? Quote Link to comment Share on other sites More sharing options...
Tim Reeves Posted August 15, 2014 Share Posted August 15, 2014 Hi. Just measured mine from the leading edge. It measured 75mm Quote Link to comment Share on other sites More sharing options...
Tim Reeves Posted August 15, 2014 Share Posted August 15, 2014 I'll see if I have still got the instructions. Won't be able to look until tomorrow as working nights! Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted August 15, 2014 Author Share Posted August 15, 2014 Thanks Tim, 75mm, 3" - so mine is a bit tail heavy. I wonder if a 45SF would be any heavier than the 40 FSR I have in it now? Quote Link to comment Share on other sites More sharing options...
Tim Reeves Posted August 15, 2014 Share Posted August 15, 2014 I have an Irvine 53 in mine and still had to add a bit of lead. Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted August 15, 2014 Author Share Posted August 15, 2014 Just swapped the OS 40 FSR for a 45 SF with JE super-quiet silencer and an 11*6 prop and that's brought the CofG forward by 3/8". OS 40 FSR - 317gms, OPS40 - 340 gms, OS 45 SF - 345 gms - those are bare engine weights, so the SF on it's own was good for 30gms. That leaves it 3/8" behind yours, I make it 30% mean chord which should be safe. With a bit of luck Edited By Bob Cotsford on 15/08/2014 21:52:09 Quote Link to comment Share on other sites More sharing options...
Hangar 9 nut Posted August 15, 2014 Share Posted August 15, 2014 82mmmm I just built PB models Bullitt and Paul says 82mm from leading edge next to fuselage! Quote Link to comment Share on other sites More sharing options...
Bob Cotsford Posted August 16, 2014 Author Share Posted August 16, 2014 82mm is 3 1/4", reckon I'm close enough, thanks to both of you Maybe I should just have emailed Paul Total dry weight is now 4lb 10 oz so swapping the engine and putting a 1700 LiFe in place of the 1300 LiPo has added 3 oz. Perfect. Quote Link to comment Share on other sites More sharing options...
Hangar 9 nut Posted August 16, 2014 Share Posted August 16, 2014 not sure how heavy mine is but mine has OS 40fsr ! Quote Link to comment Share on other sites More sharing options...
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