150% Un-Tiny Trainer Build

duckduckgoose

Well-known member
Today I was thinking about what project I should embark on next and I remembered how nice the tiny trainer used to fly, until I butchered it up and performed horrific experiments on it (Tiny Twin Boomer), but also remembered how little room there was for electronics. Still, I managed to fpv it and get ridiculous altitude for such a small plane. So here we go folks, time for a big ol tiny trainer. I took inspiration from @dharkless' 'Not So Tiny Trainer'. It's actually 153% to be exact, enough of an increase to allow the fuselage to still fit on a single sheet of FB. The wingspan should be 1460mm (bigger than the explorer!). All parts now cut out, now the fun begins!
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duckduckgoose

Well-known member
NICE!!
What electronics are you planning on using?
A sunnysky 2216 1250kv, swinging a 8x6 -9x4.5 prop, 0n 1300 -3000mah 4s , r9m receiver, hawkeye firefly q6, plus video tx and antenna, plus possibly a vector. Battery size depends on the cog and the prop depends on how much speed I feel like getting
 
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duckduckgoose

Well-known member
Fuselage done, I'm not going to worry about mounting the pushrods internally, 1) I don't have any straw to guide the wires, and 2) looks aren't that important to me. Plus I'm going to wait untill the build is complete so I can help eliminate tail/nose heaviness with servo placement. I saw an article by @Winglet where he placed the servos externally and far back close to the tail. Onwards!
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quorneng

Master member
Given you are going to place everything yourself anyway I would strongly recommend the rudder and elevator servos are placed right at the back with just short direct links to their horns as is common with ailerons. Such a linkage is no only mechanically efficient but also gives much better 'definition' to small movements and is overall lighter as well!

Any idea what it is likely to weigh ready to go without the FPV gear.
 

duckduckgoose

Well-known member
Given you are going to place everything yourself anyway I would strongly recommend the rudder and elevator servos are placed right at the back with just short direct links to their horns as is common with ailerons. Such a linkage is no only mechanically efficient but also gives much better 'definition' to small movements and is overall lighter as well!

Any idea what it is likely to weigh ready to go without the FPV gear.
Yeah that sounds good, less spaghetti control wires!. As for weight, I have no idea. The original tiny trainer I made was a heavier foam board I found here in AUS, the fuselage feels nice and light so I think it will be very sufficiently powered with the 1250kv SS motor.
 

duckduckgoose

Well-known member
Had some minor issues with the power nose, measured the wrong side of the score lines (correcting the expanded score lines for 4.5mm FB) and it ended up being loose. Nothing a little force and hot glue can't fix. As for the wing, the original TT only used a single flat piece of foam board as the spar (which I don't think would add all that much strength in an upscaled model). So I have made a box spar similar to the simple cub, but a little thicker, hopefully to add a little more lift into the wing. This will come at the cost of drag, but I don't want to go super fast anyway.
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duckduckgoose

Well-known member
Wing is Done. I added a small strip of ply across the centre as a reinforcement for the dihedral. Moving into the tail section
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duckduckgoose

Well-known member
Given you are going to place everything yourself anyway I would strongly recommend the rudder and elevator servos are placed right at the back with just short direct links to their horns as is common with ailerons. Such a linkage is no only mechanically efficient but also gives much better 'definition' to small movements and is overall lighter as well!

Any idea what it is likely to weigh ready to go without the FPV gear.
Plane is 400g with no electronics, 900g with electronics and 3000mah 4s lipo(except fpv).
 

kilroy07

Legendary member
So I had my son over (he's 32) and we (he) decided we would build a pair of 150% Not so Tiny Trainers... Picture update tomorrow (I had an issue or two up-scaling the plans.) plan on finishing/maiden Tuesday.
 

duckduckgoose

Well-known member
So I had my son over (he's 32) and we (he) decided we would build a pair of 150% Not so Tiny Trainers... Picture update tomorrow (I had an issue or two up-scaling the plans.) plan on finishing/maiden Tuesday.
It's a great sized plane at 150% in my opinion. Hopefully I have mine done tonight or tomorrow, just need to make a firewall or steal one from another plane
 

duckduckgoose

Well-known member
Done. Plane weighs almost 1kg which is pretty good considering it has a 3000mah 4s lipo inside. Still need to add some credit card braces around the bbq squewers and Velcro for the battery which sits nicely inside the tail section of the fuselage (not directly under the power pod) which should give it some protection if all goes wrong. Everything feels solid and light at the same time. Any tips for further reinforcement would be appreciated, I want this to last as long as possible.
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kilroy07

Legendary member

duckduckgoose

Well-known member

kilroy07

Legendary member
Okay so I maidened mine... tonight...
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Everything was going great until I tried a loop....
Then my plane looked like a kid's drawing of birds flying... (As in... "V")...
I got her back to the runway the ONLY thing holding the wings together was a bit of packing tape...

Next step, cleaning up the plans a bit and cleaning the fins off an arrow shaft! :rolleyes:
 

duckduckgoose

Well-known member
Okay so I maidened mine... tonight...
View attachment 138318

Everything was going great until I tried a loop....
Then my plane looked like a kid's drawing of birds flying... (As in... "V")...
I got her back to the runway the ONLY thing holding the wings together was a bit of packing tape...

Next step, cleaning up the plans a bit and cleaning the fins off an arrow shaft! :rolleyes:
Did you use a box spar or Just the flat piece of foamboard as in the original? I just keep finding more jobs to do before maiden. Added some ply strips to strengthen the mounting rods. Also building a slide-in battery tray that doubles as a skid plate for the nose. Like a swappable power pod.
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