BBA/Winter Build 2017/18 - Top Flite Corsair

[willsonman]

To get the pitch axis of the yoke animated we need another servo. Just so happens that these UMX servos are SUPER tiny and one fit right under the seat support. a bit of balsa as a support and it is going nowhere.


Here is the bottom of the whole thing. It shows the pitch axis servo mount plate in the set support position as well as the final install of the roll axis torque rod. An additional hole was drilled for the pitch axis servo leads to come through.


The next couple of shots show the stick up close. This is hand-shaped balsa. Just to be a bit different, I made this for a left-handed pilot because why not?! The main stalk of the stick is polystyrene tubing, I use a small tea candle to generate heat. wave the plastic over the flame a bit where I want to bend and the plastic softens. A more complete image of that is up next.



Here is a REALLY close shot of the mount for the stick. One TINY screw holds the brass into the plastic rod and a dot of CA keeps it secure.


Last up is the big one. The yoke, or stick, is mounted to the torque rod using a steel pin. this is free-moving in holes drilled in the brass but is friction fit into the plastic yoke. I'll secure it with a dot of CA on the inside of the tube when it is ready to be permanent. The pitch axis control rod will mount to the side of the stick and has enough play to move side-side during roll movement. The pivot, of course, will allow the fore/aft movement. You can now also clearly see the bend in the plastic tube to create the right shape of the stick.


Once I get the stick fully mounted I can do some testing for servo movement and then paint it. Installation order is as follows: bottom/back plate assembly, rudder pedal assembly, side panels, instrument panel, seat. There are lots of details to add to this after paint. Some paint highlights as well as decals. Not out of the woods yet but it is really coming together.

 

[nhk750]

Just amazing, you do great work!

 

[willsonman]

Well thank you! I was wondering if anyone was still paying attention to this build since the maiden is over.

 

[jaredstrees]

Oh, still watching with interest. And awe. I'm constantly stunned by your level of detail. I'm still happy when something I build that LOOKS like a plane!

 

[willsonman]

LOL, Me too! Sometimes I wonder how I get to the end of these projects.

Update time:

 

[PsyBorg]

Well thank you! I was wondering if anyone was still paying attention to this build since the maiden is over.

I look at every one of your posts seeing what magic you weave that day. I just don't post too much about it as I just look silly when I do hehe.

 

[SlingShot]

It looked great in the air! Very lethal. Like a fighter should.

 

[willsonman]

Ok, so I spent a LOT of time on some small details yesterday. The canopy was the largest time sink. I took the canopy completely off the aircraft to do all this work. I reinforced the lower sides with CF tow and CA. They kept on flexing causing the rea mounts to change angle and bind. It is much stiffer now and is not an issue. I further reinforced the canopy front with a former. This former was based on the shape of the front windshield of the canopy. I used two layers of 1/16 balsa and backed it with CF tow. Once installed, it was much better but still causing some issue. The final nail in the coffin was to add a squirt of white lithium grease. Perfectly smooth operation and no issues now.

I got the UMX servos operating the stick now. I added a smal piece of plastic to connect the pitch servo to the stick.


Then, I put the roll axis servo in place as well. Good operation and the movement is smooth too.


I will also note that I added some basic bearing grease to the UMX servo gears. I do not want any dirt or debris to bind them up so I figured this was a decent safeguard. I started wiring things up and discovered that the servo wires for the roll-axis servo were so loose that the ground wire had separated. I did not want to go through the painstaking work to re-solder it so I just replaced it with my backup servo. One gear was slightly damaged on that one so I had to swap gears out too. All working now. The sun has FINALLY come out today after a week and over a foot of rain in my area. Massive flooding all over the place with road damage and cars floating away. So, I hope to get out to the field to fly a little today. I need to get some paint thinner for this enamel paint I have so I cannot move forward much with the cockpit anyway.

 

[willsonman]

Paint

So I did a YT live stream last night to show how I do my airbrushing. Using Model Master enamel paint I thin with 50% paint thinner to the consistency of 2% milk. You swirl it in the container and you can see the paint run on the side. Since the pilot wore a parachute as the seat cushion, it has a lot of hardware and stuff that rubs on the seat. I used a bit of steel wool to scuff up the surface a bit. The original zinc chromate paint did sometimes smear rather than just chip so I followed this scuffing with a light pass with the airbrush. Just some basic wear here. I think it needs to be a bit more dirty so I'll do some dry brushing with graphite.


The side of the seat. I like how this turned out with smudges and the crease in the plastic looks like it has been used but is still serviceable.


Side instrument panel. I like to put on a fairly thick base coat and the hair dryer can accelerate the drying process. It leaves a splotchy look that I blend in with additional light coats. It gives depth to the otherwise boring flat surface.


THe other panel done the same way.


Rudder pedals done with a bit of scuffing as well for wear. A base coat of silver would really make it pop but I'm happy with this subtle look.


The floor and back plate done similarly to the above panels. I smudged the floor area where feet would use the pedals and then scuffed the surface for some additional and a bit different look of wear. I'm quite happy with how these panels turned out and give me a very good base to start adding color highlights and decals to.

 

[willsonman]

Ok, let's wrap this project up.

The instrument panel was cut out and trimmed on the sides due to the canopy slide rails. just a little trimming and nothing major. Black acrylic paint was applied by brush in two thin layers. The decals were cut out using my #11 blade and applied via tweezers and then pushed into the indentations with the butt end of a paintbrush. The gauges then got a treatment of canopy glue that will cure out overnight to simulate glass. I've tried using epoxy in the past but have found that moisture eventually causes the epoxy to free up against this plastic and acrylic paint. The glue will keep the decals in and make a nice surface to simulate the glass.


Using 220-grit sandpaper, I created some graphite powder and dry brushed it onto the seat. Just a touch on the bottom and a bit more liberally to the back. Just dirties things up and gives a bit more depth.


The fire extinguisher comes as two halves. Previously I had rough cut these out and then sand the backs until the edging comes off. I then used medium CA to get the two halves together and then sanded the seam to blend it. Some pray enamel paint to get the perfect glossy finish. The top is a piece of wooden dowel inside of a shrink tube. Heat was used to shrink the head and make the taper on the end of the outlet. CA to the top and its done. This will get scuffed and glued to a side panel after the red paint fully cures more.


Now the fun stuff. Colors were applied to panels and I took a few liberties here as well. I could have spent another few weeks detailing the garbage out of this but I'm happy with these results and, frankly, I'm ready for this project to be done. The first image shows the raw colors and the the next shows with a little graphite powder applied. It is VERY subtle and that is what I like. I do not want people to get really close and see brush strokes too badly. The subtlety of this will blend together making good depth from a distance and be just a pronounced when up close.

You can see the graphite applied closer to the control panel and around the map box. There is also a bit around the instruments but not as much as these are not primary controls and would not likely be touched.


The other panel here. The lever panels get a bit dirty from frequent use of the throttle and the aft, not as much. Remember this is a Marine version and the aft lever panel was for the wing fold. It was probably used more frequently as an arm rest.


Two left pictures are raw and the third has graphite. The back has little graphite applied as the seat will reside in front. The bottom panel is a bit more filthy, particularly around where the feet rest. Not sure what the yellow bit was for but... I hate painting yellow. Yellow always comes out streaky and I had to apply 6 coats to get it where it is. There is some clumping of the paint from all these layers around the edge and I hoping that will not be as visible once installed. It is the one thing I'm not happy about. Velcro prepped for the seat and a trigger dot applied to the handle as well. The head of a pin dipped in paint and one touch was all it took.


I'll move onto final electronics prep tonight and see how far I get into this install. Once it is all in there I'll look at making a gun sight as well. This will have to be done entirely from scratch so I need to have a look at reference pictures and make a plan. As of now, this is almost ready to install into the cockpit.

 

[wilmracer]

Fantastic as usual. Need to shoot some glamour shots and video in the sunlight when she's all buttoned up. She is going to be hard to tell from the real thing

 

[rockyboy]

Lots of fiddly little details - I'm a fan of just painting the inside of the windows an opaque color

Are you planning on a pilot figure too?

 

[willsonman]

Glam shots are a must. I'm going to solicit on FB for any of my local friends who are into photography and see if they want a more interesting subject to shoot.

No pilot... it will obstruct the camera. Clear canopy... it will obstruct the camera to paint the inside.

 

[rockyboy]

No pilot... it will obstruct the camera. Clear canopy... it will obstruct the camera to paint the inside.

That completely makes sense for this project - for my current level of cockpit painting skills, it's best for me to just opaque the window

 

[Tench745]

I like to use a drop of Future floor wax on instrument clusters to give them that shine. Usually takes a couple applications to get it to build up any thickness. I like the idea of the canopy glue, but I feel like it would be a bit too matte for my taste.

 

[nhk750]

Wow and WOW! Great realism and nice craftsmanship. Cheers!

 

[F106DeltaDart]

Beautiful work Josh, simply incredible!

 

[willsonman]

Many thanks guys! A more matte finish on the gauges can be a drawback but if you get too glossy it can distract from the look at this scale. JMHO.

The remaining assembly was done and connections soldered up. I connected it all to a spare Rx and it all worked fine. I ended up installing the base/back plate assembly first, and then had to connect the setup and move the stick aft and unplugging it to be able to fit the rudder pedal assembly. With that in, I snaked all the wires in and installed the panel with the throttle. Then the other panel and finally the seat. Here are the results...


I think it looks fantastic and I'm very pleased that I did not BREAK anything during the fitting. I've got some ideas for the gun sight so I'll move onto that later. I did have some worry about what would be seen through the camera. so I installed the SD card and fired it all up. Everything is visible in the recording. You can clearly see the stick movements as well as the pedals and the throttle stick is visible at about 1/4-full throttle. Obviously you can tell when the canopy is open and when it is closed as well. I do like how the focus is on the scenery more than the cockpit as that is really what you are after. All this said, the live VTx transmission does clip out a lot of this frame. I did not check what would not be seen but its likely that just the top portion of the instrument panel will be seen. I'm OK with this as again, the focus of the ride-along camera is to get the visual flight experience... not the piloting experience.

 

[willsonman]

On another note I wanted to do some tallying...
Servos: 20 total
BEC: 20A
ESC: 100A
Batteries: X2 3S 5800mAh, X1 3S 1300mAh for Rx and camera system
Channels used: 16 + airspeed telemetry

1. Throttle
2. Aileron 1
3. Elevator
4. Rudder (also linked to tail wheel)
5. Aileron 2
6. Tail gear retract (servo)
7. Mains retract (pneumatic)
8. Flaps
9. Canopy slide
10. Bomb drop
11. Cowl flaps (slaved to throttle channel)
12. Main gear doors (linked to gear retract with timing adjusted)
13. Cockpit throttle
14. Cockpit aileron
15. Cockpit elevator
16. Cockpit rudder pedals

Cost breakdown:

• Cost of the kit from fellow club member (includes cockpit kit): $20
• Retracts and air equipment basically given to me: $0
• Servos all had on-hand: $0
• Paints: $10
• Glues: $50
• Hardware - most I had on-hand: $50
• Power system: Sponsored by Grayson Hobby ($0) THANK YOU!!!
• New set of batteries $70
• Electronics: $50
• Graphics: $30
• Dummy radial: Sponsored by Carl (Wilmracer) THANK YOU!!!
• FPV gear: camera sponsored by Flite Test, VTx $20 THANK YOU!!!
• Time: ~200 hours (started 07NOV2017 - 24MAY2018)

TOTAL spent on project: $300

Reward: Sharing the build process with friends and so many spectators, making memories, and certainly attending my first SEFF with Carl.

Other thank-yous go out to Ron from my club for the kit. The price was unbeatable. Chad Veich for the tail gear design that he allowed me to use for 3D printing AND publish the design on Thingiverse. George Miller for reference pictures of the build of his version of this kit. John Morgan for inspiration and detailed instructions of building and finishing techniques over many builds.

Last and certainly not least: My family. They provide so much for me in my life and they are a shining example of how a spouse and children can encourage and support a man. Many frustrations and time here and there to allow me to do something I enjoy so much. LOVE YOU GUYS!!

 

[willsonman]

I also want to take a minute to talk about the WHY on this build. I always talk about how each project of mine builds on the previous one. The Corsair was a step up from the Bugatti. I took the engineering skills I learned there and applied it to the Corsair to do all the little gimmicks I've always wanted in an airplane over the years. The sliding canopy, the animated cockpit, functional cowl flaps, FPV camera, bomb drop... It all required very careful design considerations and making things myself. I've always liked the look of the Corsair as it is just a beautiful subject. So many folks think the same way. I wanted to challenge myself to do these little things and they really added up. Perhaps I'll do a wing fold on another model someday as investigating that was a challenge all by itself. I learned a lot, gained more skills, and reinforced good practices along the way.

My hope too is that all of you following along the way learned too. I always try to break things down so that they are easy to digest but also inspire to try for yourself. If you had had a thought along this journey that spoke to the effect of "hey I can try that too" then I have accomplished my goal for this and every other build.

On our trip to SEFF, I asked Carl which of my builds he thought was the most impressive. While I'll not speak for him I' will just say that the decision is tough. Each project I do is so different that it is hard for me to make that call. My SE5a was ALL DTFB and had LOADS of detail like this one. The Sikorsky S-39 was built from nothing to flying in 51 hours over the course of 3.5 days at FF 2015 with a total of 90 hours to completion. The Bugatti was entirely scratch-built with my own aerodynamic "guesses" along with the challenge of the contra-rotating motor design. The Corsair is STACKED with details, gimmicks, meaning, and proves what a value balsa building really is. It is impossible for me to decide which is my favorite, let alone which is most impressive.

So, just a few more thoughts for you to digest as this project comes to a close.