Adrian Smith 1

Yes I have bought one and have been flying it this summer when I can. I have been using an OS 120Fs pumper with a 14x10 APC. I must say it flies very well and does all the areos you could wish for, although landing needs care if you slow it up too much.   Which brings me to my next point - the U/C arrangement is pitiful with the legs on it no bigger than on my Cmpro Quest 50 and expected to carry 3x the weight. Also the U/C being so short it's easy to foul the prop on the floor with a bouncy arrival.   Also the ply plate housing the U/C is not up to scratch and gaveway on the second flight. I replaced it with 1/4" birchwood ply sheet and epoxy resin bandage, this has solved the problem. I also bought a better UC from Carboncopy.  Hope this is useful.

As scratch builder and latterly an ARTF constructor I must comment on the poor quality fittings and design of my latest project the Cmpro Mossie which I am using two OS 52FS motors. A recent reviewer warned about the almost impossible fitting of the wing bolts (took him a day). Due to the odd alignment of the bolts and concealed nuts in the fuz moulding, it took me a day and a half plus some Isopon filler to accomplish. The rudder fixing in the fuz attached to a push rod wouldn’t hold a feather and was replaced with my own closed loop system. Both fibre push rods were thrown away (why does Cmpro persist with these things?) as they bent like Quelch’s cane before six of the best! I replaced the elevator pushrod with a decent piece of dowel. Next came the fitting out of the moulded nascelles. The supplied throttle pushrods were barely M2 is size and had to be bent to align the throttle arm with the servo level. These rods were also discarded and replaced with better quality M2 rods due to too much give in the provided items. Fitting them gave rise to lots of swearing as due to the internal wood frame in each nascelle, which houses the servos and retract frame, not being in the same sense. This meant one of the rods was a pig to fit. Furthermore one needs hand the size of a baby to fit the fuel tanks within the moulding as there really isn’t any access. That’s as far as I’ve got. I have lost all enthusiasm for the project and am very disappointed. It’s only the initial cost outlay that’s keeping me going. I hope when I fly the thing it’s worth it.

I am a great believer in spending a few quid on voltspy battery checkers to save a few hundred spondules due to cell failure inflight. There have been a few times where I thought I had picked up the charged nicad/nimh before a flying session only to find at the field, upon installing the battery in the aircraft, the voltspy tells me the battery is not fit to use!   Cell failure is another danger and despite charging a battery, said battery proves to have expired at the field. Another vote of confidence in the voltspy checker. Also don't forget to cycle nicads/nimh occasionally which invariably throws up dodgy cells.

Thanks John. Good to hear of the longevity  of the Limbo Dancer. I wish mine would last that long!

Yes good point. I use 2.4Ghz these days but I do have some nylon covered wire I can use.

Thanks guys appreciate it and it's commonsense - as the meerkat says "it's simples!"

As a builder and flyer for some years now I have what might appear to be a stupid question. I have used the closed loop system for rudders (pull-pull) very successfully and wonder how to do the same with the elevator. Short of mounting the servo sideways I can't for the life of me see how it's done despite looking at the finished article on photos with a magnifying glass! The review of the Capiche 140 ARTF in September's mag has the system which appears to show the rudder and elevator servos on a flat plane. As I say I may be a bit dense but can someone enlighten me?

Thanks Martin - I always like to hear the users' view rather than the advertising hype. Will check them out.

I am on my second project with twin engines and decided to fit on-board glows to both engines and I really welcome some feedback on a reliable piece of kit. I am using two OS 52 four strokes by the way.   

 Hi Nik, Thanks for the input. I must admit I like to keep things simple. I had already decided on an on-board glow system for safety. I do swear by OS engines (which I will use here) hence I don't usually fiddle around with them, never needed to. I have found the four strokes very reliable in particular, using them up to 120 size. I asked the questions after reading a piece in a idle moment but I am fast going off the idea of adding more gadgets. It just there's more to go wrong. However, I am not daunted. I had a brief affair with World Models DH Comet which flew very well but I made the mistake of slowing too much on finals which prompted its spectacular demise ! Ho Hum.......   

  Hi Tony, Thanks for that. It gives me something to go on. Take your point on "one more thing to remember" with a 'heading hold' Giro! Adrian 

I have recently acquired a Cmpro Mossie which I intend to fit with two OS 52 FS engines. However, I read somewhere recently that to counter potential torque swing on take off a gyro can be fitted to the rudder (not heli holding gyros or HAL). I have no idea what to buy if this is the answer or how much? In the same vein an engine synchroniser was mentioned which in the event of one motor failure in the air or take-off, would reduce the remaining engine to tickover, thus avoiding the dreaded air/ground loop. Where can I get one and how much are they? Is this the answer? I have flown aerobatic single engine IC models for years now but fancied trying a twin but this has stopped me in my tracks. From Adrian Smith  

  By and large all the Cmpro ARTFs I have bought have performed in the air very well but experience has taught me to reinforce the U/C area as a matter of course. I have recently had to do this retroactively to the Extra 300S 90 size after a bouncy landing. However, after buying the Leo 120 it was pretty obvious to me the U/C is not up to the job. The wing loading is a relatively high 26oz/sq ft and the U/C legs are no greater than those provided with much smaller Quest 50! The Leo's U/C recess, which seems to be constructed with a eight inch poor quality liteply, soon gave way after a couple of bouncy landings. I have now put a quarter inch birchwood ply platform in the fuz insert along the nose to remedy this failure. This has lowered the U/C legs a tad but has solved the problem and I don't feather the APC props tips anymore on concrete runways.