Alan Matthews

Does anybody have a paper cut out please which I can lay onto my new engine cowelling in order to cut it to suit an Irvine 5.3?   It looks quite a tricky operation, but if and when I do my own I will try to publish a picture of my solution if nobody else has done so.   Matty

Thisis a reply to Biggles elder brother which was on an email to "alerts at modelflying" but for or some reason was not accepted so is probably not in the correct chronological sequencwe- but thanks to the others as well for the advice.     For the closed loop system on the ARTF, a length of threaded rod is passed thro' the rudder with a nut and washer on each side. Then nylon parts with a small hole in are screwed onto the threaded rod on each side for the connections for the closed loop to go to.   The rod length is not very big so that quite small movements of the closed loop cables result in large rudder deflections.   Mechanically this is never good because then even with very short servo arms one has to run the transmitter at about 50% to achieve reasonable control for fairly gentle flying.   Also it must always be best to use longish arms at both ends of any system to reduce the effects of any backlash in the system and the short length of what are in effect cranks on the rudder makes its operation more sloppy than necessary.   Does this clarify the situation a bit.   It is however not easy to set up the closed loop with the system provided with the ARTF so that all the transmitter settings are at zero (including trim), servos in the centre etc. which is where I like to start.  

I have just finished building my artf WOT 4 which was very easy - I've been flying (mostly gliders ) for 30 years and am upgrading from a Super Air with an Irvine 53 to a WOT 4 with the same engine.   One last thing is final location of the fuel tank provided.   I feel that for best location the "bung " end of the tank should perhaps be pushed thro' the hole in the engine bulkhead - but it will not quite go through - is it meant to, because if so I will have to enlarge the hole in the wood a bit.   I'm sure it will probably be OK either way, but if the bung end of the tank does not locate in the hole, then there may be a possibility for the pipes to be pulled off the tank tubes.   All advice gratefully received ( the closed loop rudder seems to work OK but is a bit of a fiddle to adjust and I feel that the threaded bar is not really long enough to match it with the servo throws properly.