David Hayward

I have just purchased the current (Mk2) version of the 1/4-scale 77" wingspan DB Sport & Scale Sopwith Pup kit. The wings are assembled from four halves and the method of fixing of the rigging wires is absolutely critical for maintaining the integrity of this model in flight - the same applies to DB's 80" wingspan SE5 biplane. The adjustable 50lb breaking-strain flying wires, and one of the diagonals made from the same wire between the interplane struts, are attached at the upper end to spring-loaded grippers fixed into, but poking out of, the underside of the upper wing structure. Also, the interplane struts which should always be in 'compression', not tension, are attached at their top end via quite powerful magnets. Does anyone have experience of the long-tern reliability of the grippers and magnets? Eddie (just retired from running the DB Sport & Scale company) introduced this Mk2 system as an upgrade of the original two complete wing Mk1 version of this Pup model so as to make assembly time at the field much quicker and, clearly, he has every confidence in the design. However, are the rumours I hear of a potential structural weakness here just 'unfounded rumours' (embellished with the telling) or does anyone have actual first-hand experience of rigging failure in flight? I note that Pete Lowe who has written a series of 'build' articles for this model in RCM&E in recent times has had some 50 or so successful flights over the last two years without any problems, with his model built exactly according to the plans. However, I note that the rumours he appears to have picked up since has now prompted him to add a second set of adjustable flying wires using turnbuckles, if only for peace of mind (ref. RCM&E Nov 2014 issue, page 73). I would much appreciate any comments based on actual flying experience that anyone has before I start this new and interesting building project.

1.  Slough Radio Control Models   2.  Al's Hobbies   3.  Graupner Super Star   4.  Horizon Hobbies @import url(http://www.modelflying.co.uk/CuteEditor_Files/Style/SyntaxHighlighter.css);@import url(/CuteEditor_Files/public_forums.css);

I know wot I like - it's the October prize please.......!

Thanks Simon - comments noted. 

I shall be grateful if anyone could advise me about the following?  I have acquired a Graupner ARTF Super Star (1760 mm, 691/4" wingspan) complete with 26cc petrol engine.  I am now setting about putting it together .  The instructions state that it has been designed for use with standard servos and, in line with this,  the model review in the February 2006 edition of RCM&E refers to use of  'cheap Futaba 3004' servos - no need for £89 digital jobs' .   S3004s are a ball-raced version of a standard S3003 but with the same standard a torque rating of 3.2 kg/cm (4.8V) and speed of 0.23 sec/60deg.  The model was put through numerous aerobatics during the review includiong flat inverted spins and benders and is said to have performed very well with this set up. I now find that Seagull has brought out its own version of the Super Star which seems virtually idential to the Graupner version (same wingspan) and is designed for similar engine sizes (1.60 2-stroke, 1.80 4-stroke). This model was reviewed in the recent RCM&E August 2008 magazine using Hitec 645MG high torque servos which have a torque rating of 7.7 kg/cm and associated speed of 0.24 sec/60deg and hence a torque rating some 2.4x higher than Futaba S3304s.  The review article for the Seagull Super Star states that one would be doing the model an injustice if fitting standard servos . Although the author of the article does qualify this by indicating that, of course, cost may be a factor, to my mind at least, this seems to throw up a difference in opinion relating to two pretty much identical models!? So, as someone who is only just venturing into larger models with bigger engines and who has quite happily used standard servos on all  models to date, should I keep my S3004s for a future, less potential racey model and purchase higher torque ones for my Graupner Super Star?........or, should I just stick with standard (torque) servos as Graupner indicate in their instructions? Bearing in mind that I don't wish to spend more money than necessary and end up with an unnecessarily over-designed model and yet wish, in due course, to have the confidence that I can throw my Super Star about the sky a bit without serious risk of mishaps, which option should I adopt?   All comments would be much appreciated. David    

I must win soon too - I'm also IN....!!

Count me in too please. David

Count me in too please.

Please also put my name in the hat.  David