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Phaedra's blog
Posted by Phaedra | Dec 20, 2014 @ 05:57 AM | 641 Views
Some progress done on the Ka8b in the last few days.
First up was the towhook servo. I had to glue a couple of sturdy support blocks onto the cockpit floor, to which I could secure the servo with the supplied screws.
Then I had to choose the longest servo arm available, to avoid that the control rod would touch the underside of the cockpit floor. I must remember to install the battery strap properly before I glue the cockpit floor in the fuselage again, taking into account the towhook control rod movement. I guess I'll glue in a couple of support blocks to guide the rod....
After a couple of tests I was happy with the servo movement, no binding, and a solid connect/disconnect position of the towhook.
Next was a bit of work on the wings. I started with the servo wires, by installing some mpx connectors to allow trouble-free wing installation. I alternated male and female on each wing, so I can make no mistakes when plugging them in.
When I started testing the ailerons, I was baffled by what I saw. In the neutral position, the servo arm was already in an extreme position, which caused quite some trouble for the up movement of the aileron. Another argument for the theory that this bird never flew....
Unscrewing the servo arm proved impossible without some extreme surgery on the wing. Removing the servo doesn't look very inviting either, since it is glued in with plenty of epoxy on the balsa wing covering.
So I had to solve this digitally, against my principles....Continue Reading
Posted by Phaedra | Dec 15, 2014 @ 02:34 PM | 1,284 Views
The Ka8b was the first one-seater glider I ever flew, and I spent quite some time seated on the hard wooden plank, listening to the squeaking of the rudder pedals while trying to keep some thermals over France.
So I didn't have to think for a long time when I found this second-hand RC model in pristine condition.
I had to spend half a day in my car to get it in Germany, and the previous owner claims he had some ten flights on it. But "it just wasn't his thing".
I couldn't care less if he flew it, but the really mint, like-new conditions makes me doubt it has ever flown. Not a single micro-scratch on the landing skid, the wheel is like brand new... And the CG marked on the wing is so far forward that I doubt it could actually fly like that.
But heck, it's like brand new, and I could buy it for a very good price, including the motor, ESC and 4S Hacker this was a no-brainer.
Only downside: it didn't have any spoilers installed (another reason to doubt that someone with very limited fixed wing experience has flown it like ten times and landed it without a single scratch).
I'm not sure which brand it actually is. The online shop he bought it from sells the Topmodel version, and when I look at pictures of that model, there are very strong resemblances, but it isn't really the same.
The fuselage is really solid, which makes it the perfect model to do some slope soaring. It has a span of 3m, the wings are a bit see-through covered and partially...Continue Reading
Posted by Phaedra | Dec 07, 2014 @ 01:27 PM | 803 Views
Today I finally maidened my Twin otter.
Maiden Twin Otter (1 min 27 sec)

I started by doing a couple of high-speed taxi runs, to get a feel of the controls.
During the second run, the model already took off, and it landed again after I cut the throttle.
I felt confident enough after this short test, so I decided to give it a go. I had to give it a firm pull on the elevator to take off this time, and as soon as it was airborne it felt really harmonic in response to the controls.
Center of gravity was a bit aft during the first few flights, resulting in a bit nervous behavior in pitch.
Another flaw was ground control. Somehow the nose gear has very little authority on the ground, making it almost impossible to make simple turns after landing (unless at very low speed, almost a crawl)

But all in all, this is a winner, very happy with the result.

So the next step will be to improve on nose wheel steering, and finish some more details (painting, cover the landing gear legs,...).
Posted by Phaedra | Nov 26, 2014 @ 02:40 PM | 1,528 Views
The Twin Otter is nearing completion.
The toughest issues have been tackled: the motors and motor mounts, and the nose wheel steering.
The motor mounts are made of thin plywood, and the motors are attached via Z-bent wires, which are then glued to the backside of the mounts. A first engine run proved it to be solid enough.
The prop savers that came with the motors had a big problem too for this configuration: the hex bolts are very very short. This is especially difficult because I want to use three-blade props. Since I had some Pichler prop savers available, with the same diameter bolts, but much longer, I transplanted those.

The nose wheel steering was solved by using a piece of shrink-tube that serves a some sort of hinge. I glued the shrink tube to the nose wheel piano wire and to the control rod, and then applied a bit of heat to further shrink it.
So far, it seems to be working just fine. Time will tell....

Next steps are:
- solder the other ESC to motor and solder a Y-cable for the battery to both ESCs
- fix both ESC at an appropriate place
- finish the top part of the engine nacelles
- weight and balance
- finish transmitter programming
- FLY it!

I hope to maiden next weekend...
Posted by Phaedra | Nov 04, 2014 @ 03:30 PM | 2,100 Views
While the glue was slowly setting on my Twin Otter model, I had a pop-up idea...
Last year I build a depron pusher-prop F-22 that flies fantastically.
So why not build an indoor micro-version of it?
I still had some micro components lying around that I bought for some undefined indoor model that I wanted to build.
I printed out the plans on one A3 sheet, which seemed to be the perfect size for this purpose. The only problem seemed to be the size of the propeller, or better: the size of the cutout in the model is not proportional the the required propeller size on this scale. But I guess that can be tackled. By making a larger cut...
I first tested the electronics, by binding the micro receiver to the Spektrum module in my Taranis transmitter.
Soldering the motor wires proved quite a challenge on this scale, but ultimately I got it to turn in the right direction.
I glued the motor to a depron motor mount, not sure that this will be solid or strong enough. Time will tell.

Next step will be to find a place to mount the micro servos for the elevons. Transmitter programming was easy enough since I already have a larger version of this model, so I just had to make a copy of the model memory.

Only a couple more hours and this thing will fly. Can't wait to see if it really does...
Posted by Phaedra | Oct 30, 2014 @ 03:29 PM | 2,236 Views
As the indoor flying season is approaching, the time has come to dust off the lighter stuff.
I bound the two scratch-built indoor models to my Taranis first, and then I dug up the plans of an indoor DHC-6 Twin otter that I received from a fellow club member.
I admired how wonderful this model flew last winter, and I gladly accepted his offer for a copy of the plans.
So while I started the build of this model, I ordered some motors, counter-rotating 3-blade propellers, ESCs, servos, a 2S450 Lipo and some lightweight wheels.

So now it is time for cutting, bending, glueing.....
Posted by Phaedra | Oct 19, 2014 @ 05:01 AM | 1,852 Views
Model airplanes tend to grow bigger and bigger. They do.
And on top of that, they don't really stack well in a car. Not even in a large family car (in European terms )...
So I bought a second-hand closed trailer, and started mounting some racks inside, just to get some better view on how I can organise things neatly inside.

My first idea is to put the models nose-down, hanging form the racks, and immobilize them with some soft material and elastic bands.
Problem is, if I want to add a second set of models behing that, I run out of length of the trailer. And so I would need to overlap the wings of the models, which might get complicated/dangerous/tricky.

Another option would be to stack them when they are lying horizontally, nose left and tail right for instance.
Then I could add another stack that has the tail on the right and the nose on the left for instance, allowing an easier overlap.

Or I could replace the ugly black box that was mounted in front by something more useful, like a space where the wingtips could protrude, so that I could have two stacks behind each other without overlapping wings...

I'm sure anyway that I will replace the black box by useful space, maybe even some sort of storage for my flight cases with batteries and transmitter, or other smaller stuff.

Plenty of time to think of solutions, with winter ahead....
Posted by Phaedra | Sep 01, 2014 @ 08:59 AM | 1,807 Views
Had a wonderful dive yesterday, to discover this sunken C-47 near Kas in the south of Turkey. We were able to swim inside, through the open cargo door, up to the entrance of the electronics bay and cockpit. It was way too narrow to continue any further. I wouldn't risk getting stuck inside with all the diving equipment sticking and hanging out of our body....
We had to leave the wreck a bit early because one of our diving partners ran out of air fast, but it was quite the experience!
Posted by Phaedra | Aug 25, 2014 @ 05:43 AM | 2,230 Views
I would like to join some fellow club members to go slope soaring anytime soon.
Only problem is....ain't got no slope soaring model...yet.
Or so I thought.
I just remembered the small glider I once bought, on which I learned to fly RC.
It's a DG300 from Graupner, 2,3m span.
I used a bungee at the time to launch it, and the model sure shows the abuse it had to take during those first flights.
It's only a 2-channel model + speedbrakes. But I will convert it to ailerons to get better control during slope soaring.
It has about the right size and weight to get started I think.
Let's get to work then....
Posted by Phaedra | Jul 28, 2014 @ 04:03 PM | 2,437 Views
Finally got to make my first in-flight video by mounting my keychain camera on the fuselage in front of the tail.
If you look for it, you can see me standing on the short strip parallel to the runway, and in the back you can see real airplanes taking off from the real runway....

Hurricane routine 270714 (4 min 54 sec)

Posted by Phaedra | Jul 20, 2014 @ 11:23 AM | 2,569 Views
After loads of good advice and help from a fellow club member, I finally succeeded in getting this vintage electric helicopter ready to fly again.
The gyro on it didn't inspire much confidence anymore, so I replaced it by a Spartan one that I could borrow from that same club member.
Yesterday I did a good effort in cleaning the dust out of every little spot, and putting some oil here and there in the articulations and bearings, and now everything seems to run smooth as ever.
I tested the correct movement of the servos without the blades on, for my own safety. Tail rotor and gyro seem to do what they're supposed to do.
Next step is to take it to the field and have it inspected and probably fine-tuned a bit more, and then it's time to get it back into the air again!
Posted by Phaedra | Jun 24, 2014 @ 11:58 AM | 2,759 Views
Today my Spitfire kit arrived.
I'm kind of fond of the Spitfire, I like its profile in the sky. Already having an Eflite Hurricane made me doubt for a while if I really wanted this kit, being almost the same size. But since it's a Spitfire, and it's balsa instead of foam, I decided to go ahead and order one, before they go out of production again.
And so the box arrived today.....
First impression: very nice!
Everything was neatly packaged, as can be seen in the pictures.
At first sight, the quality of the different parts seems very good, and the covering looks really well finished.
On the bottom of the wing, cutouts need to be made for retracts, wheels and aileron servos. Confusingly enough, markings for wheel wells were made on the covering, but in the wrong place! I was a bit too fast on the trigger there, and already started cutting the covering when I noticed my mistake. Frustrating, but recoverable...
The drawings in the manual don't provide you all the details where the cutouts need to be made, and you still need to be a bit of a creative builder to find out what to look for.
When I made the cutouts for the aileron servos, I noticed that a piece of string was integrated inside the wing, which is very handy to pull servo extension wires through the wing to the fuselage. Nice touch!

Inside the fuselage, sleeves have been glued in for elevator and rudder. They are only glued at the extremities, which allows for some bending when under load, and that could...Continue Reading
Posted by Phaedra | Jun 13, 2014 @ 07:17 AM | 2,665 Views
I bought this helicopter second-hand around 1993. It was one of the first electric helis around at that time, and when I saw what a friend of my brother could do with it, I knew I wanted one.
I had never flown any helicopters in my life, and in those days they didn't have those little coaxial, or fixed pitch thingies, or even a simulator to help you out. So I was on my own.
I bough a book about it, to at least learn how to set it up correctly. I did some trials while it was securely attached to a table, with short strings of rope, so it could hove at some 10cm above the table, and I could watch the reactions to my inputs.
But that's about as far as I got, when we bought a house and then raised a child, and everything of my RC hobby went straight to the attic.
I took up RC flying again a couple of years ago, in 2012, and in the meantime I have restored a couple of models form the nineties into active duty again. It's probably cheaper to buy new foamie models today, but I find it more fun to accept the challenge and to see these models fly again. Nostalgia isn't a stranger to me....

And so I came across this piece of antique ("vintage" is the hype term now...). Last winter I learned to hover my fixed-pitch MSR-X, and that now gave me the courage to dust off this one.
I took it with me to the field, to show it to some fellow members that have been flying helicopters for a while now, to get their opinion about my chances of having this fly again.
They...Continue Reading
Posted by Phaedra | Jun 11, 2014 @ 11:03 AM | 3,017 Views
After a very nasty crash on its maiden flight, it took me the best part of 6 months before I was even able to look at the remains of this model.
It went straight down into the ground, on its nose, only a meter or so from where I was standing.
It's still unsure what exactly happened, but when it passed overhead, I pulled it into a turn (that wasn't really a good idea, in terms of orientation) because of field limitations, when I suddenly saw it go into an abrupt spin, straight down, and it felt like I had no control whatsoever.
At first I had no clue what happened, so I accounted it as pilot error. But when I investigated the remains, I found one of the aileron clevices broken. Was it the cause of the crash, or a consequence? We'll never now, but I did replace all of those plastic clevices on this model, just to be sure.

So last winter I decided to bite the bullet, and start the restoration on this model. Meanwhile I had ordered a complete spare model, intending to use only the bare minimum from it, so that I can build me another one later, when I get to grips with this one.
The damage was impressive: the fuselage was broken in two and deformed, and so were both engine nacelles.
The landing gear could, to my own surprise, be repaired, but both motors, spinners and propellers had to be replaced. All in all, a surprisingly limited list of parts that needed to be replaced, especially considering the fact that she went straight on the nose into the ground!

This is...Continue Reading
Posted by Phaedra | May 26, 2014 @ 07:44 AM | 3,000 Views
When visiting my LHS a couple of weeks ago, I saw a beautiful model hanging form the ceiling, second-hand, for 330 Euro, including an internal combustion engine and starter.
Since I have a really soft spot for the Marchetti SF260, I asked them if they wouldn't sell it without the motor, because I only want to fly electric.
They didn't, so I studied the model carefully, and found out it was from Mantua Models. A bit of research showed that is now a very rare model, discontinued, and only a couple (literally) of build logs and flight tests are available.
Those were all very positive about the model, so then I knew I wanted one
The only unknown for me at that point was which motor I needed, because none of the build logs were about an electric version, so the total weight remains a mystery...
I soon found one on sale via eBay in France, for 129 Euro, still new in the box, to be built. Now that is definitely a better price than the one in my LHS, so I quickly decided to buy it.
And whaddayaknow, today the postman rang at my door, and he had a very large box for me

It was incredibly well packed, with lots of paper and foam around the actual box, so that is already a big plus.
Wings and tail part are abachi-covered foam, and appear to be of impeccable quality. Included are lots of plastic parts for engine cowl, tip tanks, etc.
Flaps are not foreseen, but I think I will add them anyway. I have no idea yet about wing loading.

The first thing I did after unpacking,...Continue Reading
Posted by Phaedra | May 15, 2014 @ 02:39 PM | 3,863 Views
Last time I flew my Hurricane, I broke off the canopy while opening it up to install a new battery, so I took advantage of this mishap to try and modify it to a sliding canopy.
First step was to cut the canopy into two parts: one that will remain fixed as a windshield, and the other part will be the sliding part.
On the corresponding Hurricane thread on this forum I found the idea of using a C- and an I-profile to make a sliding rail. So off I went to the LHS, and there I found the required profiles in plastic.
The first problem to tackle was to cut a slit into the closed square profile, to make it a C-profile. But that proved to be easier than what I had feared.
A bit of tinkering was required to reduce friction as much as possible, without introducing too much play on the mechanism.

Then it was time to cut slots into the foam, to house the rails, and glue in the rails.

...Continue Reading
Posted by Phaedra | May 10, 2014 @ 10:50 AM | 3,048 Views
The weather being at an all-time low these days, I decided to get a bit more organised for charging batteries.
I have an older power supply that worked well as long as I only charged one battery, but wit my new Hitec quad-charger, I ran into its limits while charging four batteries simultaneously.
Another problem is that this power supply is a bit cumbersome to take with me to the field, being a bit heavy and such.
So my first idea was to replace it with an older 300W PC power supply I still had lying around. Being a switched power supply, it is a lot lighter, and its form factor is a bit more interesting too. It's easy enough to convert these power supplies to what I need:
  • On the largest connector, connecting the green wire to any black wire will switch the system on
  • The yellow wires supply a 10.7V voltage, so for 300W that means a maximum current of almost 30A, which should be sufficient for my needs
  • I wanted to cut all unneeded wires and connectors, but care has to be taken with this. Luckily I went about in a systematic way, cutting wires one by one, because some of the orange wires need to be tied together for the power supply to function.

I had an old aluminium flight case that I didn't use anymore, so then I decided to integrate the power supply into this:
I first cut out a few pieces to make openings for the cooling fan and power cord receptacle:

Two small screws hold it down in the corner of the case.
I drilled some holes in the power supply case for some...Continue Reading
Posted by Phaedra | Apr 30, 2014 @ 03:11 PM | 3,386 Views
Dusting off my good old ASW22 with the intention of installing a new frSky receiver and bind it to my new Taranis radio, I noticed a problem with the spoilers.
I was setting the control throws for all channels when I noticed that both spoilers didn't extend equally anymore. And that could cause a really bad day when that happens in flight (don't ask how I know).
At the time, some 20-odd years ago, we didn't have the same choice in digital or metal gear servos as we have today, so this model wasn't designed to house the spoiler servos in the wing, but instead they opted to install only one inside the fuselage, and you just had to hook up the spoilers each time you assembled the wings.
I took an alternative path at the time, since I didn't see myself doing that operation before every flight. So I opted to screw a small servo tray to the wing root, and make openings in the fuselage where those servos would pass through. Not quite elegant either, but it worked for me.

Now we have much smaller servos, and more powerful than the bulky stuff from those day, so I wanted to mount new servos inside the wing.

The hardest part is making a cut in the wing, not knowing what you will find below the surface. In this case, it was some sort of plywood spar, only glued to the top part covering of the wing, and only loosely glued to the wing root.

I decided to cut it and glue the servo solid to the remaining parts of the spar, thereby restoring its structural function, using some expanding PU glue.
The glue dried meanwhile, and I finished adjusting the throws for a nice synchronized movement of both spoilers.
Mission accomplished so far.

I will cover the holes temporarily, so I can finally remaiden this beautiful bird as soon as the weather permits.
Tomorrow I will install the telemetry sensors, and do the final fine-tuning.
Stay tuned.
Posted by Phaedra | Apr 22, 2014 @ 01:39 PM | 3,046 Views
After fooling around with the 50mm EDF version of the T-33, I finally built up some confidence to fly EDF jets. I preparation of my Windrider B-737 I bought an Epic Victory from Graupner a while ago, intended as a trainer, but the many hours I invested in that model in modifying it has made me anxious to fly that one too
So the T-33 came in handy to get over my cold feet about all this, and whaddayaknow, my self confidence inspired me to take things up another level, with this SU-35.
I have studied a couple of Youtube clips about this model, and it seems to be quite a stable flyer indeed. Having an 80m concrete runway available in my club, I feel confident about pulling this off. But then came the surprise: these models seem to be harder to find than I imagined. Hobbyking has them, but in backorder, and they are about the only shop that still carry them on the European continent.
So I was more than pleased to find one second-hand, complete with motors and servos, extra main gear struts and a 15A BEC, for the same price as the empty model at HK.
So yesterday I assembled the model outside, and did some inspecting, so I can make a list of things I still might need and what is still required to do to make it airworthy (it hasn't even flown yet!).

1) Control horns on the tailerons have too much play. At first sight, the screws only need some tightening, but I'm not sure they are up to the task, considering the leverage required for moving these large surfaces.
...Continue Reading
Posted by Phaedra | Nov 15, 2013 @ 03:14 PM | 3,726 Views
With winter approaching, a new indoor flying season starts. My new flying club organizes weekly indoor sessions, and that got me thinking: I have nothing to fly! (sounds familiar? "I have nothing to wear"
The tinkerer in me wants to build something, and since I'm already working on a Jamara lasercut kit of the SF260, I opted to build an ultra-simple and ultra-light version of this beautiful plane, in depron.
I already have some 3-views that come with the Jamara kit, so I resized them to a 60+ cm long version, printed it and started cutting some depron....
I slightly oversized the wings, to get the wingload down. I will be making the wings of 2 layers of 3mm depron around a carbon tube.
To be continued....