I am building one balsa kit this year, and it is a Sig Kobra. It's a smaller version of the King Kobra that Robert Pike started building a couple months ago at one of the TEMAC building classes.
This kit produces a smaller version, about 45" wingspan, of this speed/pattern sport model. It calls for a .19 to .35 glow engine, so I think my high-speed 25-size 4S system from my now demolished EF-1 racer will be a good fit. It's a simple 4 channel model (no retracts; no flaps), and I think it's a good size for TEMAC. I can probably bring it to the field assembled. Converting it to suit an electric motor and battery will be part of the fun. The kit includes many printed parts (not die not laser cut) that will need to be cut out by hand.
Should be nice. Colour scheme?
Michael,
I have always liked that plane. I have never built or flown it but several people way back had and warned me to reinforce the wing ribs that hold the slots for the main landing gear. They usually supply slotted basswood LG blocks that glue into the rectangular slots in the bottom of the ribs towards the centre. There is a bit of a plywood doubler for each rib but usually not the full length of the rib.
The Kaos series of planes from Great Planes had the same problem (built 3 of them). I sistered 1/16 plywood to the full length of the rib that had the LG blocks and never had a problem. On all scratch-built planes I have built I have made the slotted LG mount one continuous piece of pine (trimmed 1x2) that acts as a joiner for the two wing halves.
For what it is worth.
Frank
Colour scheme? I don't know. Maybe something Canadian? Probably dependent on what leftover colours of covering I have.
Thanks Frank, I'll reinforce the landing gear blocks.
An internet search found a similar electric conversion that was successful with the same power system.
I was thinking of using two aileron servos (one in each wing) instead of one mounted in the center of the wing, and I was considering using electric retracts, but I decided to try to keep things as simple as possible. It also means no aileron linkages visible on the outside of the plane.
Quote from: Frank v B on December 24, 2017, 04:29:18 PM
Michael,
I have always liked that plane. I have never built or flown it but several people way back had and warned me to reinforce the wing ribs that hold the slots for the main landing gear. They usually supply slotted basswood LG blocks that glue into the rectangular slots in the bottom of the ribs towards the centre. There is a bit of a plywood doubler for each rib but usually not the full length of the rib.
The Kaos series of planes from Great Planes had the same problem (built 3 of them). I sistered 1/16 plywood to the full length of the rib that had the LG blocks and never had a problem. On all scratch-built planes I have built I have made the slotted LG mount one continuous piece of pine (trimmed 1x2) that acts as a joiner for the two wing halves.
For what it is worth.
Frank
I would definitely offer two cents, but pennies are out of circulation now, so I'll spring for a whole nickel. 8)
Andy
Having fun !!!
I've decided to use one servo per aileron, as opposed to one servo for both as per the instructions/plans. That will in fact be simpler.
Wing is complete; just needs a bit more sanding and then ready for covering.
Carved wingtips, cap-strips, landing gear blocks and servo bays.
Nice work, looks very good.
This is a classic. Nice looking work Michael. Can't wait to see it up close.
Fuselage well underway.
Blind nuts in the firewall for motor and nosegear; formers and triangular balsa glued in.
Note the printing on the inside balsa fuselage sides. The plans are essentially on the wood.
Wing 'hold-down' dowel; tapped hardwood blocks for the plastic screws; smooth wing-fuselage fit; tail temporarily pinned in place.
Does this come with limbo pole collision avoidance technology?!! 8)
Andy
Fuselage is taking shape. Battery-hatch built, and nose will have a air-intake scoop at the bottom front of the nose, sort of like a P51D Mustang.
Looks nice Michael.
Tail fillets.
More sanding.
Rudder servo installed.
Nose wheel installation took several hours!
Beautiful Mike!
More vicarious pleasure!! 8)
Andy
Looks great Michael.
Here is your routine to practice "classic pattern". This plane should fly this schedule very nicely!
Ed
I think this thread is all a ruse: Michael will turn up with a finished E Flite Leader!!!
Hey Ed,
Thanks so much for posting the great GBR/CAA Clubman Schedule (F3A aerobatic manoeuvre descriptions). This would be a super addition to a fun fly, and would help the LHS sell more planes. 8) Imagine doing this in formation!!
Here is a link to their web site: http://www.gbrcaa.org/clubmanmansch.htm
Detailed schedule calling card and ribbon drawings are here: http://www.gbrcaa.org/Schedules/Call_Cards_Clubman_2015.pdf
Their practice simulation video is here: http://www.gbrcaa.org/sportsmanschedulevideo.html
Cheers! Andy
Sorry to derail from michael's beautiful build but just wanted to encourage anyone who has never tried flying any of the routines be it IMAC or F3A based I would highly recommend they give it a shot or ten. Positioning the airplane and flying straight lines really teaches you to fly to a new level.
Derailment over
Ed
I will definitely try to fly that pattern.
I've started covering. 2-servo modification shown.
More work on the wing, and a wing tip.
More covering.
Tail.
Looks great.
Canopy, masked and spray-painted (at work).
That looks beautiful! I never thought to do it that way. I always hand brush.
Main construction and assembly has been completed. I'm finishing the radio and power system installations, and then I'll do decals.
Looks fantastic!
Beautiful, Michael! I really like your colour scheme. This will make an excellent photo subject against a blue or cloudy sky! On white it will look like the wings, top of the fuse and the top of the rudder/fin are separate entities flying in formation!!
Bravo!!
Andy
Very nice!
Your builds get better and better!
Glenn
Done.
Fine balancing and throws still to be adjusted.
very nice!! can't wait to see her fly
Wow, you should be proud of that!
What a pretty looking plane.
It looks just great.... what a good.
Beautiful! You've inspired me to work on mine! I hope I can make it happen for the Spring :o
Hey! How did you end up treating the plastic turtle deck? Did you cover the top of the fuselage and paint the plastic, cover the plastic, or paint onto the fuselage film?
I found a blue spray paint that closely matched some blue covering. I used 4 different types of covering with varying heat/stick/melt temperatures, and this made covering more difficult than planned. It worked out, but it was challenging.
The plastic was spray painted, and attached by screwing at 2 locations into balsa (glue re-enforced holes) blocks.
The 2 screw-heads match up with 2 hold-down magnets under the canopy-battery-hatch.
Cool! looks great! Thanks for the details.