Please feel free to post something and photos about what you are doing in the club or where you have been flying. Please choose at least 1 category, E.g. Activities for your post to help others find it.
Stuart Chambers recently sent in a photo of this build by his No. 1 son. Does anyone recognise it? (of course Stuart knows the answer) Feel free to post your answer comment here or if more convenient over on our Facebook page.
We have had a couple of enquiries lately about whether powered flight is allowed on Dartmoor. The simple answer is No. As there may be visitors to our area intending to fly on Dartmoor and use our website to search out the best sites to soar, John asked for a statement to be added to our home page to reinforce our constitution and the advice given in our Dartmoor site guide.
“It is worth reminding club members and others visiting Dartmoor to fly RC that whilst non-powered flight is allowed, any form of powered flight whether electric or combustion is banned by the Nation Park Bylaws. Due to this importance this bylaw it is written into our constitution and included into our guide on flying on Dartmoor.”
An electric palm sander is a wonderful thing! If only I’d had one in the 70’s I could have filled the whole bungalow with balsa dust rather than just my little bedroom. Oh and the wonderful smell of cellulose dope… those were the days. And mixing my own diesel fuel… I regularly bought Amyl Nitrite and Ether over the counter in the chemist at just 15 years old! Anyway, back to the build…
After quite a lot of sanding:
Adding the fuselage fairings to the wing roots:
Then the wings had their final sand:
What you can’t quite see behind the winglets is, what was going to be the outer 4 cm of flaperon is now a short section of trailing edge with built-in washout. Will that prevent the nasty tip-stalls I’ve been warned about? We’ll have to wait and see.
To help achieve ‘more up than down’, the flaperons needed horns that were raked forwards. I couldn’t find any for sale so made my own using bits of plastic from an old bucket:
So here she is with her control surfaces pinned on just for the photo…
I don’t know about you but I always like to start with the wings.
Using root and tip rib templates cut from some old aluminium I made a couple of ‘rib sandwiches’ using up bits of scrap 1/16th balsa and new ply for the root ribs. It’s a method I used ‘in the old days’, does anyone else still do this(?) I have no idea but I do think tapered wings are well worth the extra effort.
Building semi-symmetrical wings on a flat board required quite a bit of careful packing but before long the wing halves (one left and one right – hopefully) were mostly done minus the full length flaperons, winglets, and washout. Oh, and minus the fuselage fairings that would eventually cover each root (what?? – more on that later).
The fuselage was even more fun to build. Again, the plan was to use up lots of bits of scrap balsa (I hate waste) through creating a sort of ‘exoskeleton’ whereby the hard/curved outer skin of 1mm ply was fitted first then the thickness built up by adding strips of soft balsa internally. Curvy parts of the top & bottom were strip-built too.
I don’t have any kind of jig so I glued on the fuselage sides back-half-first making sure the fin was truly vertical before pulling the nose together a few days later.
Then the strip-work began in earnest until of all of my short 3/32, 1/8, and 3/16 scraps had gone.
Clothes pegs are great!
Whilst waiting for glue to dry I made up the sliding servo tray using a scrap of plastic cable trunking, a bit of old ali carpet strip, a bit of 1mm ply and off-cuts of light mahogany. Much more fun than transmitter programming(!), well, I think so anyway.
Underside view showing the internal strips and bottom strips going on:
At this point I decided to find out about setting up the flaperons and posed a couple of questions on the Model Flying forum which proved most informative (https://www.modelflying.co.uk/forums/postings.asp?th=167572&p=1). More news soon.
I thought you might be interested to see my new slope soarer design which carries on from where I left the hobby in 1980. The repeated design/build/fly/crash, design/build/fly… cycle which dominated much of my spare time in the 70’s, culminated in this rugged 2-channel model I still have 40 years later.
My new design uses the same boxy fuselage construction – full length thin ply sides, soft 1/4″ balsa top and bottom – but instead of 1/16″ all-sheeted wings I’ve copied the open-frame Kloudrider wing construction but with a semi-symmetrical section and higher aspect ratio.
I’ve designed things with ailerons in the past but not flaps. I rather fancied doing both this time but I’ve never really understood why control surface movements try to make different parts of the wing behave in different ways at the same time. So, I decided to go for full length flaperons (which I’ve also never done before) and to try the old ‘sliding servo’ way of mixing the controls which I heard about in the 70’s but never tried.
(By now you’ll have worked out that I’m some kind of weird old-timer who doesn’t want a foamie, doesn’t like programming, but does like a challenge!). “No wonder they used to crash” I hear you say.
The fuselage shape is influenced by the ASW 15 and 17 but I also like the way the 28 is concave on the underside of the fuselage. I also fancied having a go at a T-tail as I’ve never done one of those either. Oh and those little winglet things too – they look like fun. I decided to make the front end pretty big so I can get all four servos in and still have plenty of room for my fingers which don’t work as well as they used to. Anyway, that’s enough waffle for now. Here’s my hand-drawn plan which I’ve already deviated from slightly… (more in the next post):
Thanks to John for organising a ‘back to our roots’ slope soaring day at Black Hill last Sunday. There was a good turn out and we can see from the photos and video clips posted over on our Facebook group that members had a great time and demonstrated their skills of soaring without any power aids. Stuart Chambers has sent in some photos. Check these out on our Gallery page and the launch photo chosen to head up our home page. Thanks Stuart.
An an update on Johns 1/3 scale K7 build:
Progess on the K7 has been up and down yet quite a few more hours put in. The fin is virtually complete and covered in .4 ply and built integral to the fuz so nice and strong.
I have also finished the rudder which will be operated by closed loop and hinged with Robart Hinges. What has been apparent is the abundance of laser cut parts supplied with this short kit, comparatively little stock wood needed so far, and in the majority of cases they fit firmly together like a jigsaw. I have built nothing on the plan as the laser cut parts dictate positioning….brilliant so far!
Also nearing completion are the 2 elevators, again lots of precut parts. These will be driven by 2 wing servos in the tailplane, never be down that route before. Again the tailplane parts include a ply servo tray especially for this. As this build is so large things are made easier by big pieces that do not break in your hand and seeing what you are doing with older eyes much better. Onwards.
Our aero-tow on Sunday was blessed with some dry and very warm weather. The event was well attended with Felix from the Okehampton Model Flying Club kindly providing the tug with his Titan. It was also good to meet some new members for the first time and we hope they enjoyed the event also. There were a wide range of classic scale gliders that showed off the high quality building skills of their pilot owners. It was very impressive to see them follow the tug up to around 1000 ft before releasing. Unfortunately the wind was from the NE and there was not much lift around although Joe managed to find a thermal on his final landing approach and promptly abandoned that in favour soaring up – and up until that pocket of lift disappeared. We also had a few e-gliders that had their flights during refuelling and lunch breaks. Cliff’s Bird of Time with his recently added e-pod flew well. The flying site seemed to have it own “Bermuda Triangle” of gorse that seemed to pull a few gliders off their initially central landing approach up the strip into the adjacent gorse to the muttering of their pilots. Some photos from the day are below and hop across to our Facebook page for more from our members and comments about the day.
John has sent me an update on his 5 metre K7. It is looking impressive. I can see John looking out for volunteers to help carry this beast to a launch site. I am looking forward to adding further updates to our Gallery.
The 1/3 K7 short kit arrived from Laser Cut Sailplanes sometime in June and a while after that SLEC sent the wood I had ordered in order to begin construction. They were very quick, just a couple of days.
Progress on the fuz was reasonably quick and straight forward after some considerable plan studying had been done. Many of the pieces slot together very accurately but sanding jointing faces to the right angle before gluing was necessary at times. I did have a couple of ‘lining up issues’ but if you have a modicum of building behind you they are fairly easily overcome with patience. I have recently completed the 0.8 ply cladding and the nose skid. PTFE tube is installed in the rear enclosed area of fuz to direct the closed loop cable to the rudder. The nylon covered fishing trace slides easily inside. None of the construction so far is built over the plan, I have the fuz plan hanging from the ceiling near the bench for easy reference, however you do need space for a model this size and I am fortunate to have just enough, the wings will push things! Many thanks to Maggie for looking interested.
Chris, Martin, Mike and I went up L.H this morning. I gathered from the experienced pilots comments that finding a thermal was challenging and conditions lumpy although the weather was clear with a light NW breeze. It was good to see Martin back flying today and I just managed to capture his launch before his craft became a dot in the sky. It is our home page photo for this week. I tried to capture other launches but was too slow for their rapid assents.