I finally got to fly the Mini Scalar that I spent the winter assembling and painting. The plane flew surprisingly well, requiring just two clicks of aileron trim. Surprising is putting it mildly, since I had to set up all incidences myself, my first time ever doing so. Nothing beats beginners luck. The plane is overpowered to say the least. I have never had a plane this powerful, ever. the 6s 4000mah battery was a good match and has enough power for two schedules pr. flight. I’m happy to have a new favourite practice plane for those quick out-to-the-field-before-wife-notices practice sessions. But I need more batteries, can’t stand waiting for them to charge at the field. And no, the props is not broken – it’s an Aeronaut folding 14×10 propeller, something that proved to be less than clever when used in combination with a motor brake on the ESC. A fixed prop is now on order, this plane really needs to slow down on the downlines and you can imagine how fast it is when the motor brakes – the prop folds and you have less, not more drag!
Topic: Mini Scalar
Getting closer! Last nights work saw the final piece of film come in place. I’ve also hooked up all the servos with their respective linkages and surfaces and glued all hinges. Now it’s just radio-setup, bellypan and canopy to go. More pictures on Flickr
I’m in the process of covering the flying surfaces and painting the fuse. To see how I create checkerboards like these, see the images on Flickr. I use post-it note cutouts to test the size and shape, then I cut a plywood template before stapling pieces of covering film in layers on the workbench and cutting them out using the template as a guide.
The fuselage is spray painted using a spray can from the local hardware store. Not great but it taught me a lot about how NOT to paint fuselages. I’m hoping clear varnish and trimlines will cover up the worst mistakes. pictures will follow. (And yes, the paint/covering scheme is exactly the same as on my Calypso.)
The tail is done, all hinges in place and everything seems to line up pretty good. The plugin assembly is all home made and sadly it also looks that way. Nylon screws hold the wing so that the model should be easy to assemble at the field. I have also completed the servo installation in the wing. The cutouts were already made for a flat servo installation. It’s a little more work than with upright servos but it proved to be well worth the effort. Many new pictures are uploaded to Flickr, you can take a look at them here
The elevator pushrod is made from carbon rod (5mm hollow) with 2mm solid split ends. The assembly uses the extended pushrod technique that I successfully employed on my Saphir, where the pushrod end extends into a former in the back of the fuselage just under the stab. Very rigid and there’s no need for supports along the inside of the fuselage. This was surprisingly quick and easy to make but it requires access to the rear fuse through the stab slot so it’s not easy with ARF’s.
It’s starting to look more and more like a plane now. Fitting wings without ANY guidance or markings whatsoever is a bastard job and one that makes me wonder why this fuse was moulded without holes for the wing tube or any other markings. I have an incidence meter but before we get to that, I have to drill my holes straight. Easier said than done.
I’ve test-run the Kora motor on the workbench. Because this is very dangerous to do, please observe the following method which I’ve found to be quite safe:
1. Make sure prop and motor is firmly in place with motor, ESC and receiver connectors checked.
2. Read instructions, ignoring the warning about throttle channel reversing. After all, there is no servo.
3. Connect the battery
4. After confirming the fact that the motor does not run although it should, scare yourself to death when pulling the throttle all the way back while the motor revs up to full power.
5. Realizing that you’ve just had a near-death experience, disconnect the battery and change your underwear.
6. Re-read the part about throttle channel reversing and decide it might be a good idea to check it after all.
7. Set the throttle channel to normal direction (it WAS reversed)
8. Try again and hold on for dear life
9. Tell others about your experience so that they too may live to tell their grandchildren about it.
The new prop for the Mini-Scalar has arrived. It’s a 14×10 Aeronaut Cam-prop. I’ve tried a small version of this on a glider setup once but not the complete package with spinner and all so I was curious to see how German it all turned out to be. The answer of course, is: Very. It’s a beautiful piece of kit, and if it makes my plane look like a glider so be it, I’m saving weight and getting thrust so what could be better?
While the Lasers are stored away waiting for summer, my autumn project is finally underway. It’s an electric 50-size model called Mini Scalar from Peter Adolfs in Germany. It has a 164cm wingspan, glass fuse and bellypan and balsa sheeted foam surfaces. It is not so much a kit, you just get the glass and sheeted parts and off you go. No formers, templates or nothing. The wings are well made though, with plug in stuff ready made and tips, LE and TE are sanded perfectly. The plane has a removeable canopy and bellypan and is perfect for access to the internals. The goal is to have a user-friendly winter and F3A practice plane which can also serve as building practice. The fuselage will be spry painted and the wings covered, something I have not done in years.
It will be electric. (I may have said something about electrics in the past, words like “never” comes to mind but I belive in responding to change over following a plan) Power will come from a Hobby King 6S 4000mah LiPo, controlled by a Kontronik Jive 80 ESC. The can in front is a Kontronik KoraTop 20-14W as seen in the photo.
I chose the motor because it was recommended by my local pusher. I chose the version with the most RPM/v because I don’t want to swing the biggest props. The fuselage is not nearly as big as, say a Sebart Angel S 50, so I need more RPM on smaller props to avoid torque. I will enjoy experimenting with everything from 12×10 up to 14×10.
The Jive regulator is the best out there. But how can I say that, I have not tried it and I am no expert on electrics. Well, since it comes with an indestructo hard case which protects its extremely expensive innards, it’s the best regulator I can buy if you ask me! I can’t belive why other manufacturers does not do the same. The case is well designed and is even waterproof, although one can argue why when the rest of the setup (motor, battery, servos, receiver) most certainly is not. It has a very powerful BEC so I may not have to have a backup receiver battery, which saves weight. The Jive 80 is far more powerful than the 80 amps imply – sources say it outperforms regulators for F3A use with far higher advertised capacity. It’s just Kontronik being cautious. And you can add a heat sink to the metal surface of the regulator, increasing its potential so 10S use in 2-meter models is not a problem. And best of all? It has an F3A mode with adjustable motor braking for smooth downlines.
Based on experience from bigger models, Graupner servos will be used. DS8077 cheapies will control rudder and elevator, and C3041 minis go in the wings.
Build progress so far is u/c attached, battery compartment formers made and glued in, firewall under construction. Pictures will follow.