Canada 150 build...err, assembly...err, project

Started by Wingnutz, April 28, 2017, 11:24:22 PM

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Wingnutz

The Project Aircraft
As part of Centennial year celebrations, the RCAF put together a special aerobatics demonstration team, the Golden Centennaires. The aircraft selected for the team was Canada's basic jet trainer, the CT-114, the same aircraft the Snowbirds would use and...fifty years after the Golden Centennaires...are still using!
Produced by Canadair, the aircraft has proven reliable and relatively inexpensive. It also is fully aerobatic and flies more slowly than a combat jet, making it a great airshow aircraft. When flown in aerobatic team demos by Canada's best military jet pilots it is an iconic aircraft we should all be proud of.
I've built two in Snowbird colours(Simon would call it livery), the first gave its airframe in the name of research and the second is entering its fifth year of flying without a scratch, except for belly landing scars(no landing gear)
The project will be a CT-114 in Golden Centennaire colours.
PS I posted this from an iPad and sometimes depending on the platform you're using, images invert. LMK if this happens and I'll try to do future posts from a PC.
DOWN WITH GRAVITY! UP WITH LEVITY!

Wingnutz

#1
The Model
I wanted to try an EDF CT-114, but I wasn't up for the challenge of a scratch build. CT-114 ARFs and kits are scarce and five years ago, I could only find one ARF/kit? which claimed to be suitable for EDF. I purchased one from Greenair Designs, a small Canadian online retailer and after several weeks, it showed up. I was prepared for the fact that the model was small...about 900mm ws but,...
Surprise!
My CT-114 in EDF form was actually...a ...Tutorbolt (cross between a Tutor and an A-10)!
The first picture below shows how Haoye(the Chinese manufacturer) went about solving the EDF thrust problem with a CT-114 fuselage.
For a modeller who enjoys scale models and flying, the Tutorbolt missed the mark by light years.
My first effort consisted of throwing out the A-10 motor configuration, opening up the rear of the fuselage, cutting extra air intakes in the canopy, stuffing one of the two supplied 55mm fans in the fuse and powering it with a single 3S 2200.
Power was marginal at best. Anything less than a perfect hand launch resulted in a very short flight and another nose job...the model is beer cooler foam and although it's light, it does not like crashes.
After one season, it was time for another airframe and a different power system.
Nobody was offering even the Haoye version for sale and I ended up importing three Haoye models directly from China. The first of these(second picture) was modified according to posts in the RCCanada thread on this model...large cheater hole in the bottom of the wing, 55mm Hyperflow fan, 50A CC ESC, 1800 4S battery and further enlarged rear fuselage. The increase in thrust coupled with bungee launches made a huge difference and #8 (lucky?)has yet to crash.
DOWN WITH GRAVITY! UP WITH LEVITY!

sihinch

Fabulous project and a great thread Bill! I can't wait to see the new livery.

I love these projects!

Way to go!

Wingnutz

Took a time out from the Tutor project to finish two models for Mayden Fest, but got back to the workbench today.
Next on the Tutor is fitting the 55 mm edf into a fuselage that's really too small. One of the pictures above shows how tiny the efflux opening is on the real Tutor/stock model. Increasing the exhaust diameter is accomplished by cutting four 9" slits forward from the tail, parallel to the fuse centre line and CAing depron wedges into each slit.
Once that was done, foam had to be cut from the interior of the fuse to accommodate the edf unit.
A tapered thrust tube was fabricated from a page protector using the edf at one end and the pill bottle in the picture at the exhaust end. So far, the tube is taped with 3M 600 but my experience has been that it will let go after a while. Anyone know what kind of glue will stick page protector plastic?
DOWN WITH GRAVITY! UP WITH LEVITY!

bweaver

This is looking like a great project. 

I would suggest drilling a number of small holes into the page protector, EDF and Bottle at various locations where you wish to secure it to the EDF and the Bottle.  Then use epoxy to glue the page in place allowing some epoxy to squeeze through the holes.  Smooth the oozed epoxy on the inner and outer surfaces of the components. The dried epoxy through the holes on the page protector, EDF and Bottle will act like pins preventing the page from dislodging and keeping it in place. 

It may work.  But no guarantee.

piker

I would scratch the plastic, both surfaces being glued, aggressively with course sand paper and use a skim coat of epoxy.  The roughness should give the resin something to grip.

Wingnutz

Bruce, I don't think I was clear about the pill bottle. It's simply there to provide shape for the fuse and thrust tube during assembly and fits the category "Remove before flight".
I will perforate the tube joint overlap area and scuff it vigourously before applying the epoxy.
You raised the issue of anchoring the thrust tube in the fuse...I plan to glue it to the edf shroud and the inside of the fuse but only at the exhaust opening as the onside of the fuse is anything but a smooth tapering cylinder...
enough anchoring?
DOWN WITH GRAVITY! UP WITH LEVITY!

octagon

Hey Bill, what a great project! Will you try and do it in the Snowbirds colours. I would not be surprised if Callie already has the graphics for it. Looking forward to seeing it fly!
What could possibly go wrong?

bweaver

I kinda like the pill bottle.  It is a step up from the Tim's cups I have used in the past.


Wingnutz

Quote from: octagon on June 26, 2017, 07:23:38 PM
Hey Bill, what a great project! Will you try and do it in the Snowbirds colours. I would not be surprised if Callie already has the graphics for it. Looking forward to seeing it fly!
Rob,
I've done two already in Snowbirds colours(see reply#1). This one will be done up in Centennial (1967) Golden Centennaires colours (I have the GC graphics from Callie already)...the colour scheme the aircraft wore fifty years ago before they were painted in Snowbird colours.
Seemed a fitting choice for Canada's 150, but doubt I'll get it done by July 1...will however fly it in 2017.
DOWN WITH GRAVITY! UP WITH LEVITY!

Wingnutz

Quote from: bweaver on June 26, 2017, 10:52:24 PM
I kinda like the pill bottle.  It is a step up from the Tim's cups I have used in the past.
I would have used a Timmy's cup (I think there's one hiding in one of the photos) but it's too big. Small cups at Tim's were lost in the super size me Americanization of a Canadian icon (Tim's coffee cups)...while I'm on a rant here, WTF is Canada's only MLB team doing picking Budweiser as it's official beer?
I'll settle down and behave like a good Canadian now, but it annoys me we so easily give up many of the things which make us different from our neighbour and ally to the South...glad we're not trading in Trudeau for his American couterpart!
Okay, now I'll settle down and return to model airplanes...with a Canadian flavour!
DOWN WITH GRAVITY! UP WITH LEVITY!

Wingnutz

Back to the Tutor bench this morning, soldering, binding and checking the motor rotation as the EDF unit will be glued in once the fuse halves go together.
Programming the TX for the new model provided some entertainment. I forgot to unplug the battery while I was setting up throttle kill. Somewhere in this process, the throttle went to full and since the motor and thrust tube were loose on the bench, the result was quite spectacular with the motor and tube dancing around on the battery/esc wires and me madly trying to grab the plug!
DOWN WITH GRAVITY! UP WITH LEVITY!

octagon

Quote from: bweaver on June 26, 2017, 10:52:24 PM
I kinda like the pill bottle.  It is a step up from the Tim's cups I have used in the past.


Quote from: Wingnutz on June 27, 2017, 08:39:06 AM
Quote from: octagon on June 26, 2017, 07:23:38 PM
Hey Bill, what a great project! Will you try and do it in the Snowbirds colours. I would not be surprised if Callie already has the graphics for it. Looking forward to seeing it fly!
Rob,
I've done two already in Snowbirds colours(see reply#1). This one will be done up in Centennial (1967) Golden Centennaires colours (I have the GC graphics from Callie already)...the colour scheme the aircraft wore fifty years ago before they were painted in Snowbird colours.
Seemed a fitting choice for Canada's 150, but doubt I'll get it done by July 1...will however fly it in 2017.
Bill, I remember the Golden Centennaires will. In fact, one of the guys on my ATC course back in 1972 was a pilot on the team. He got married and his wife was so worried about what he did for a living she convinced him to give it up. Imagine, flying a jet at 350 miles an hour 20 feet from another jet, what could possibly go wrong?
What could possibly go wrong?

Wingnutz

#13
Rob,
Have to agree...four feet apart, lots can go wrong. The Snowbirds cancelled a number of early shows this year, so they could practise and lower the odds of something going wrong...still, pretty risky business...
Worked a bit more on the GC Tutor and got the Golden Rods (cable variety) for the elevator and rudder in place. The model doesn't come with rudder but I like rudder and I think I can fly better with one. One more step and I think I can close up the fuse.
DOWN WITH GRAVITY! UP WITH LEVITY!

Wingnutz

Happy Canada Day Everybody!
My 150 project won't be finished today but still plugging away at it.
Thrust tube has been glued as per Piker's suggestion, elevator drive cable and torque rod adjusted and painting started.
DOWN WITH GRAVITY! UP WITH LEVITY!