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Feb 16, 2018, 04:29 PM
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Servos!


Now this part was a little tricky.
Glued the empennage in place properly aligned with the wings - easy peasy.

But then it was time to connect the push rods and glue in the servos.
Used push rod linkage stoppers to make it easy to adjust the push rods to the exact right length.
I also wanted to install the servos fairly far back in the fuselage as this model tends to end up nose heavy.
Finally got it done, but it took a bit of work. Not difficult - just tedious getting it just right.
Tested servos with the servo tester included in their tool kit.
Very nice to have as I don't yet have a battery with the right connector.

First picture shows the servos glued in place, but the excess push rods not yet trimmed.
Second picture shows servos connected to the receiver. Tight fit which is good as you don't want them disconnecting in flight!
Tip from "aelflyer" - glue servos to both side and bottom of the fuselage so they won't move in flight.
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Feb 19, 2018, 11:36 AM
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Sport Wing


Did a much better job with the leading edge of this wing than with the polyhedral wing.
The secret for me was proper lighting so that I could see exactly what I was cutting (and not cutting) when making the aileron bevels.
Deviated from the build video sequence a bit in that I found it easier to cut the ailerons and bevels before gluing in the servos.
Picture below shows servos, linkages and control horns positioned just before gluing.
Also shown is my hemostat - an essential tool for this sort of thing.

Now if I had only ordered some batteries I'd be ready to maiden this thing!

Later, rick
Feb 23, 2018, 08:12 PM
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Finished model


Found an acceptable 3S battery, bound my transmitter to the model and adjusted all the servos and surfaces just right.

Entered the world of sub-trim to electronically center the servos that were slightly not at 90 degrees.
That's an interesting concept that I won't attempt to explain as there are plenty of google references.

Made one mod to keep the wing rubber bands from creeping into the aileron / wing cutout.
So I'm ready to go awaiting suitable weather!

Pictures below show the finished model with poly wing (no ailerons), with sport wing (ailerons), and a close-up of the mod.

Don't intend to paint it - if anything maybe a few decals or sharpie objects to aide orientation.

Cheers, rick p
Feb 27, 2018, 09:44 AM
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Successful maiden flight !


Now the pressure's off.
Though we've had a mild winter, I was waiting for a day that was not so breezy.
My patience was rewarded as last Sunday had just enough wind to make it interesting.

The soccer field I'd been eyeing was busy, so I settled for a nearby chunk of undeveloped prairie.
One last check of CG and control surfaces and I tossed her into the wind at full throttle.
With a 3S battery she rocketed out of my hand and climbed aggressively.
Only had one battery at that point, so I tried a lot of maneuvers to check her out.
Loops were a piece of cake, and rolls were faster and tighter than expected given that I was flying the 3 channel version.
Stalls were gentle - it dropped one wing and slowly spiraled toward the ground.
Not quite a spin, but I wonder if it can be made to spin - need to try that next time.
Hmm - maybe if I cut away some of the lower rudder to allow room for more elevator travel?
The suggested low rate setting of 70% was too much like full throws, so I'm going to decrease that.
Glides were excellent, particularly considering that I intentionally had the CG a bit forward.
No trim was necessary, but I'll revisit that after nailing the CG.

Final comment - as the 3S was so powerful, I just picked up a 2S battery to try.
Want to understand 3S versus 2S performance differences before stocking up on batteries.
By the way, I got five minutes out of the 3S and used 62% of its charge. Thinking 6 minutes is possible.

Cheers! rick
Sep 23, 2018, 07:27 AM
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Batteries


After many flights using both the 2S and 3S I've come to the conclusion that both will work, but I like the 3S better.
The 2S give adequate power and 5+ minutes of flight time, whereas the 3S is a rocket ship with 5+ minutes.
But as they only deliver 230mAh, you have to use a bit of throttle management to get that 5 minutes.
I've hit LVCO with each if I'm on the throttle too much, which is one reason I prefer the 3S - you can have lots of fun at half-throttle.
Net-net - the 2S is good for easy cruising with the 3 channel wing, while the 3S is great for aerobatics with the 4 channel wing.

You may notice that I'm using 230mAh batteries, whereas FliteTest recommends 850mAh.
I ordered their recommended battery, but was disappointed with its weight - too heavy to easily balance the model.
The 230's easily give the correct CG, with room to adjust fore and aft as desired.
And the Tiny Trainer really shines with a neutral CG, giving surprisingly nice inverted flight with little forward stick.
A little staying inverted with the polyhedral wing, but a piece of cake with the speed wing.
Last edited by rickp; Sep 23, 2018 at 07:53 AM.
Sep 23, 2018, 07:42 AM
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Flaperons


I used a six channel receiver rather than a four channel specifically so I could implement flaperons.
With the DX6i transmitter, you do that using the dual -aileron wing tail mix.
When flaps are deployed, both ailerons deflect down the amount set in the DX6i flaps parameter.
I'm using 75% - meaning both ailerons are deflected downward 75% of full throw.
A full stick turn then has one aileron full down and the other only 25% up - seems to work fine.
You do a get significant nose up movement if you deploy the flaps at speed though.
That can be mixed out, but not by mixing flaps into the elevator - for some reason the DX6i doesn't support that.
But you can mix gear into the elevator - so you need both gear and flaps activated to mix out the flap ballooning.

The 75% flaps gives lots of extra lift, slowing you down nicely for landing, but it's really just for fun.
Interesting that you could alternatively implement spoilerons using a negative flap setting.
That might be useful if I ever try slope soaring.
Sep 23, 2018, 07:57 AM
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To paint or not to paint


Wanting to decorate the model, I spent a lot of time pondering my options.
I considered paint, tape, sharpies and decals; finally settling on making my own decals.
Turns out that you can easily print custom decals on full 8.5 by 11 label paper.
Found some Avery label sheets at my local Office Max and went to work.

First I built a Tiny Trainer PhoenixRC model so I could try out different paint schemes.

https://www.rcgroups.com/forums/show...postcount=2799

Settled on a black and white scheme inspired by the Citabria, which shows up nicely on the brown paper skin.
But how to scale it up from Phoenix size to full size? Couldn't print the full size plans and the tiled were messy.
Ended up scanning in the physical model wing, stab and fuselage images as references.
Then printed out lots of test pages on regular paper, cut them out and test fit to the model.
When I had it right, I then printed the final decals on the label paper.
I carefully (and tediously) cut the final decals out and stuck them on the model.
Very pleased with the result, though it will be some time before I know how well they stay in place.

And by the way, it's not all aesthetics as the decals make it much easier to keep model orientation.
The all brown model almost fooled me several times!
Last edited by rickp; Sep 23, 2018 at 08:10 AM.
Oct 04, 2018, 05:27 PM
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Hi there.
I am just discovering Phoenixrc and your models.You are a true artist!!!! Thanks for sharing.
Do you plan or know where to get a L-13 Blanik and a Weihe 50 ?
Thanks a lot.
Kind regards
Manuel
Dec 28, 2018, 03:59 AM
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Rick,

Seen your work on phoenix models, I hear that AccuRC are looking for experience people to help with a massive fixed wing update they are working on. Maybe you could drop them an email? Their heli physics are imo the best out there and its far cheaper than other sims. Im 100% confident that they will do the same with fixed wing. Maybe you could drop them an email [email protected] ?
Jul 30, 2019, 08:03 PM
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Xb-70 valkyrie


Hello, rickp
beautifull work on all your plane builds, plus a super eye for detail, especially thr sr-71. I do fly it the most everyday. Just thought i'd ask, will there be a xb-70 valkyrie on list "to be built". Your detail on these planes and your everything is top notch. It would definetly be great piece to fly. Please reply and thank you for your time.
Reguards,
mark the "trikesta"
Mar 04, 2020, 12:59 PM
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Freewing SU-35 Build


Going to attempt to blog the Phoenix SU-35 build.
Blender will be used to create the 3D model, Inkscape to paint it and Phoenix Builder to make it flyable in Phoenix.
I'll describe each step, but not specific Blender, Inkscape or Builder commands as those are discussed further in my Liddle Stik tutorial.

https://www.dropbox.com/s/v4dhhleaaj...0v2.4.pdf?dl=0

Just beginning work on the Blender 3D model.
The three screenshot are of reference 3 view that I'll base the 3D model on.
Given I couldn't find any plans with sections, the 3 view and Freewing picture will be my references.
I size the top view for a100 Blender units wingspan, knowing that will scale correctly in Phoenix Builder.
Then draw a sizing box (yellow cube) that I use to get the side and top views accurate.
This is an important first step - get it wrong and you suffer later!
Last edited by rickp; Mar 07, 2020 at 09:48 AM.
Mar 05, 2020, 08:43 AM
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Fuselage


After studying the 3 view and pictures a bit, the fuselage is essentially three cylinders - a center cylinder holding the pilot, with one on each side for the engines. Each cylinder will need to be shaped a bit, of course, but cylinders are good starting points.
Mar 05, 2020, 09:32 AM
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Nose


The highlighted vertices were extruded to the left and then sized down to form the nose tip.
The rest of the nose was then shaped using multiple loop cut and slide operations followed by sizing to match the nose outline.
Quicker than it might seem with practice.
Mar 05, 2020, 09:40 AM
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Canopy


Similar to the nose, the canopy shape was created with multiple loop cut and slide operations followed by sizing to match the 3 view outline.
After that the canopy bows and lower boundary were added using the cut operation.
Not to worry - Blender loop cut and slide, sizing and cut operations are discussed thoroughly in the tutorial.

https://www.dropbox.com/s/v4dhhleaaj...0v2.4.pdf?dl=0

As a final step, the fuselage was copied, creating an identical object named canopy glass.
After that, glass vertices were removed from the fuselage object, and the fuselage vertices removed from the canopy glass object.
The result was that the fuselage and canopy glass objects lined up perfectly with no overlap.

Hope this is making sense!
Last edited by rickp; Mar 05, 2020 at 07:04 PM.
Mar 05, 2020, 07:08 PM
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Tail Cone


The tail cone was constructed using the same techniques we used for the nose.
Referring to the screenshot, the left most highlighted vertices were extruded and resized to form the tail tip.
The other vertices were then inserted and resized to match the 3 view outline.
Mar 05, 2020, 10:45 PM
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Engine Intakes


The engines started out as cylinders, but now we need to square off the intakes and complete the exhaust.
Squaring off the intake is made easier by creating a "helper cube" in the shape of the square intakes.
Then we carefully move the front engine vertices to match the square cube outline.
Mar 05, 2020, 10:50 PM
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Adding the airfoils


But it doesn't look much like an airplane until we add the wings, stabs and fins.
I start with a symmetrical airfoil from an earlier project and then extrude and resize it to fit.
Wing screenshots are shown, and the stabs and fins were created using the same technique.
Mar 05, 2020, 10:53 PM
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First prototype


So what's it look like so far? Pretty much like an SU-35 with lots of panels missing.
Still work to do, but at least it now resembles an airplane.
And in fact we could get what we have now flying in Phoenix, but not yet!

Next step, I think, will be to create a larger central fuselage to hold everything together.
Then perhaps we'll add the gear. Tomorrow.
Mar 06, 2020, 10:03 AM
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Fuselage "Glue"


Though it looked kinda like an SU-35, we need something to unite the fuselage nose, engines and airfoils.
So I created a new cube and massaged it until it seemed about right. This is the artistic part of creating a 3D model.
When you don't have accurate plans, you wing it based on photos.
First cut looks reasonable for now, so moving on to the gear.
Mar 06, 2020, 10:08 AM
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Gear


For the first cut at gear I initially copied and pasted the Mirage gear from an earlier project.
Needed to raise all the other objects up a bit so the gear rested on the red "horizon".
Also moved the main gear in toward the fuselage a bit.
And though it's not critical, I put the gear in layer 2, with the rest of the model in layer 1.
Placing different objects in different layers comes in handy at times.


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