David Ovenden

Managed to get some work done on the Condor today. I have altered the wing design a bit from the plan which was drawn in the 70s and seems overengineered by today's standards. It was also designed to be a one-piece wing (82" span) but as I am making plug-on tip panels I decided to use carbon fibre tube instead of the many heavy ply wing joiner/dihedral braces on the plan. I also knocked up a cutter for the 14mm holes in the ribs and got some ribs cut. The balsa "shortage" is starting to change my thinking. One of the ribs is cut from 2 small pieces of balsa from the scrap box glued together rather than start a new sheet of 3/32"! The  templates come from the ply doublers "rescued" from a BT Kingfisher model. So 2nd time around. Also did some gardening, went for a 1hr walk and fixed the fence!   Edited By David Ovenden on 10/11/2020 16:41:49 Edited By David Ovenden on 10/11/2020 16:44:05

Hi Lorenz, Yes, the colour scheme details are from a very old (1967) Flying Review magazine. The video I posted of the large RC model flying in Switzerland is finished in blue/orange with tail markings as you describe. So I'm sure you are right. And you are ex-Swissair! I have started making templates today ready to cut out the wing ribs.

Here is my (very poor) photo of the model that inspired me at Old Warden on a grey overcast (and wet) day in 1983. And below how RCM&E featured it the same year in sunshine and with blue skies! Anyone remember / know the builder of the model? I seem to remember he was Bob?? There are some nice colour schemes to chose from: I like the American Airlines orange and blue, but am tempted by G-AEWE as its an British reg and I have silver and red Solartex left in stock! There are plenty more to though!

Been doing a bit more thinking about the project, partly inspired by finding the photos of the model I saw fly at OW in 1983. The model was also featured on the cover of RCM&E the same year. I found that too. Given the balsa shortage situation I dug about and found I had more wood in stock than I thought, and have all I need for the project except some lite ply that I will use to replace birch ply for lightly stressed components. The plan shows one piece wings which are bolted on to the fuselage. But my current thinking is to build separate centre sections with plug on panels each side. Like this it would be much quicker to assemble. It also led me to contemplate making interchangeable electric and glow lower wing centre sections. Best of both worlds? The idea would be to make 2 identical basic lower wing centre sections at the building stage . I would finish the electric version and test fly. If the model is a success I could build the nacelles and fit glow motors to the second centre section. Or more wild still. Make interchangeable bolt on "cassettes" to fit either the electric motor and mount module or the i/c engine plus tank & throttle servo unit into the nacelle? I've done it once before on a Hawker Tomtit and it all worked fine. Model is still flying after 20 years. The advantage of this is that I only one centre section to make and one undercarriage unit to build. But how to make the engine nacelles suitable flexible to accomodate everything? I'm working on ideas for this. Yes,  there would be issues of balance (without the 2 lipo packs) and trim (different power types and output characteristics) to factor in. But the ailerons are in the top wing only and one cold have a different model memory for each set up? And then  I could chose between the sweet sound of two four strokes in synch and the plug and fly convenience of electric. At least at the moment we have time to work on new projects/ideas when we can't go flying. Edited By David Ovenden on 08/11/2020 08:20:42 Edited By David Ovenden on 08/11/2020 08:22:08

Martin Thanks for the link. You are right, all the info is in the other thread so no need to go over it all again.

I need a lot of 1/8 x 3/8 balsa strip for stringers on the next model. I don't have that size in stock but I do have some hard 1/8" balsa sheet. I am tempted to use this to cut my own stripwood. What is the best balsa stripping tool you have used? I am tempted to make one; but if there is a good one easily available that might be easier. What is your experience of the various commercial cutters?

Chris, I am in no doubt about the quality of Laser engines, nor the huge advantage of having a matched pair. I am currently just investigating my options. I have not entirely ruled out using electric motors.Though I do love the sound of four strokes! Jon's comments re the Enya have been read and taken on board.

Posted by Jon - Laser Engines on 03/11/2020 08:21:59: Ah ok Eric, the pun didnt make it through the internet. As for the enya 53 they are really good engines. I have one in an airsail tomahawk and despite being completely clapped out it runs well. Finding a TN version might be tricky as most, including mine, were air bleed. True Jon, But new TN carbs are available as a "spare part" so I could possible upgrade an older model to a TN carb.

Whilst a pair on "matched" Laser 70s would be amazingly good. A cheaper option for me would be another of these. Enya 53-4C . A good one with the TN twin needle carb and black rocker cover would be great! Anyone got one?

Hi Jon Looking to do the fixed version to save weight. There is not much room in the nacelles (once a fuel tank is fitted) either! 2 x 70 lasers would be nice. Are they in stock? Edited By David Ovenden on 02/11/2020 08:37:47

Looking to build a smaller version than this though! Curtiss Condor Edited By David Ovenden on 02/11/2020 08:32:42 Edited By David Ovenden on 02/11/2020 08:39:00

Back in the late 80s I bought a Curtiss Condor plan from the USA. I had seen a model flown at Old Warden scale day and really liked the look if it. I have been meaning to built it all this time. it has been a long-standing project. Now with lock-down looming it seems time to actually do it. The model is an 82" span twin engine biplane model of the 30s airliner. Originally designed by R Schweizer in 1970 there is room for some design improvement and lightening, but basically it is a good plan. Originally designed for two .40  2-stroke engines. The version I saw fly in the 80s was "just about" powered by two 1st version OS 40 4 strokes. But how to power my version in 2020? All up weight should be around 5kg I have 2x Saito 45 four strokes I could use. However, one is fitted in a model I regularly fly (Hawker Tomtit) I do have an Enya 53 4 stroke that would be great to use. It is powerful and has a better profile to fit in the cowls - with rear mounted cams and pushrods. But I only have one, and they are no longer available. I could go electric and have several 4S 3700 lipo packs that might be suitable. However what motor to use. I imagine a 42mm can with about 700kv would be about right with an 11" prop? My usual SK3 motor brand seems to have very limited availability at the moment. Choices choices! So glow or sparks and which engine to use? Edited By David Ovenden on 02/11/2020 08:24:35 Edited By David Ovenden on 02/11/2020 08:40:06

Yes, looking at the recent posts I would say its time to start a new thread about "alternatives to balsa" or "building with foam board"

Peter Thanks for the info. My preliminary settings for rudder and elevator throws were pretty close to yours, so that's good news. I've still not sorted the ailerons but will see what they are like in due course. Currently, I've just been setting up the computer mixing to be ready. Rich, I have taken over someone else's build of the Hutson Tiger Moth.. They had done a great job building from plans and laser cut parts, but decided to leave the hobby. I was fortunate to pick up the project. So I can't claim much credit for the build. However, as requested, here are a couple of photos of the plane. As you can see its, a work in progress. Still need to complete the wings. Regards David