Ford Tri-Motor (Zorn - 1:33) in SCADTA colors

Last week I printed two kits to build. A coin decided the Ford would be the first of the year (the Savoia with the late engine will come afterwards).

The model is the Ford Tri-Motor (scale 1:33) designed by Peter A. Zorn, Jr. and originally published by Crown Publishers in 1982. As some of you may already know, Mr. Zorn allowed the digital restoration of the kit, and its free release. It can be downloaded from http://www.papermodelers.com/f…s.php?do=file&id=1080

The airplane is Ford Tri-Motor 5-AT-D (cn # 111) serving for the Colombian airline SCADTA with register number “C-61” and the name “Cartagena”. The model I will build represents the plane as it looked in the following photo:

[Blocked Image: http://web.me.com/scadta/Scadta-Fluggesellschaft/Ford_Trimotor_5_AT_files/flugzeug_no_xx_cartagena_500-filtered.jpg] 
Photo form: http://web.me.com/scadta/Scadt…t/Ford_Trimotor_5_AT.html

As far as I know it is the only existing photo of the “Cartagena” on the web. On the background you can see Tri-Motor 5-AT-D-106 “Tarapaca” also from SCADTA with the wing cargo compartment open. You can also see the burnt remains of the fatal crash of Tri-Motor 5-AT-B-6 “F-31” from SACO. That SACO Tri-Motor is the same plane in which legendary tango singer Carlos Gardel died, so we know the photo was taken at Medellin the last week of June 1935.

The digital kit of the Tri-Motor offers 11 different liveries. But this SCADTA version is not included. I re-painted this version on December 23rd, and has some slight changes respect to the original kit:

Since the kit is for a 5-AT-B version with rounded door and small window behind the cockpit, the details were modified accordingly. The 5-AT-Ds had a square door and the small window behind the cockpit was removed. Seats were redesigned because 5-AT-D planes used aluminum seats (not wicker). Some small details were also modified on the nose. I decided to keep the circular bathroom window because I plan to detail its interior, and it would not make sense to put details inside if they can’t be seen.

It will not look exactly like the original, but I’ll be happy if I can make something very similar.

The kit was laser-printed on 150gsm cardstock. After measuring with a caliper I found the thickness of the sheets is 0.27mm, which is quite good since the pages of the original 1982 book are 0.26mm thick.

The model is built from the inside, and the first step is to assemble the seats.

First: print the parts. The arms and legs of the seats were slightly modified to make them look more like the ones used in “D” Tri-Motors.

Second: carefully score, cut, and fold. Don’t forget to color the edges. I use Prismacolor pincels for the edges.

Third: calmly and precisely glue the parts.

Fourth: repeat until you have enough seats for your Tri-Motor.

Fifth: thank God I am not building a 400-seat Boeing 747.

Next in the process is to assemble the passenger cabin and the bathroom.

Quote from Gummikuh

DEar Ruben,

nice, to see/hear from you again. The more with such an interesting build.
I guess this ship will offer more details than spanish constructions

Maybe the other construction report will be of help for you.

Cheers

Till

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Thanks for your words Till. It is really useful to look at the other reports.

Work continues on the interior.

First, I would like to show one of the additional details: the fire extinguishers. According to the 1929 instruction manual, there were two on the Tri-Motor. One near the door can be seen in some photos strapped on the floor behind the rearmost seat, and in some cases hanging besides the toilet’s door. The second is attached on the floor behind the pilot’s seat. In some photos the second extinguisher can also be seen hanging from the front bulkhead, besides the pilot’s door.

Apparently, the extinguishers used in the airplanes had a handle used to pump the chemicals out of the nozzle in the other end.

The kit does not include parts for the extinguishers, so this is scratch building.

I tried to get a similar shape by means of a tightly rolled piece of paper, a pin, and a couple of triangular pieces of paper. After assembled and glued they were painted with golden ink to give it a metallic finish.

Those “extinguishers” are just 12 mm tall (half inch). The straps and bracket were made with paper and cardstock respectively. I know they look terrible in the photo, and not well-proportioned. But in real life they are so tiny and look so different! (Damned unforgiving macro photos!!!!)

The first extinguisher is installed before the rear bulkhead is mounted for easy positioning.

This side photo shows all the seats glued plus the extinguisher, the toilet, and the water tank. The toilet is included in the kit, while the water tank is also scratch-built.

The right wall accessories are mounted before glueing the wall to the rest of the cabin. The wash bowl is included in the kit. The design is quite simple but very effective.

I have not found direct photographic evidence of how the cabinets looked like, so they are just my guessing. I only know they were aluminum parts painted with lacquer. I opted for a simple look, which should work just fine and in accordance with the rest of the design. The cabinets are simple scratch-built box-type objects, very easy to design by hand in a couple of minutes. I spent like fifteen minutes building them and adding the accessories.

The white smaller box inside the left cabinet represents the first aid kit that was included as standard equipment in the Tri-motors. There is spare toilet paper too (just another tightly rolled paper). On the right cabinet you see the hand towels. They were imitated using tissue paper. Both cabinets are barely half inch tall (12mm tall).

Inside the rear bulkhead you get the hinged door, and the toilet paper.

Now… why to put so much detail in the toilet compartment? As I use to say: even if it can’t be seen, I’ll know it’s there!!!

After details are added, is time to glue the right wall.

More angles of the work until now. You will see one cabinet has a mirror (a piece of kitchen aluminum foil).

The only thing that is left to be added is the “jump seat” used by the flight assistant, located just on the door. I will add it later when the cabin is fully closed.

One final note: the seats of the Tri-motors matched the interior walls. However I decided to use the green cushions because that color adds more contrast and life to the overall looks. And since the interior of the fuselage will be mostly dark once closed, a bit of contrasting color was needed in order to see something through the windows.

See you soon

Ruben Andres

Closing the roof is a bit tricky. Not difficult, but it requires certain care. The original instructions suggest gluing the arch flaps as the final step. I found it was easier for me not to follow the instructions this time. I glued first the vertical side flaps (A), and just after that I glued the arch flaps. I glued the side flaps (B) and the rear flap in the end. By doing this it was easier to glue and hold the arch flaps and curve the roof. The same applied for the smaller front ceiling (first glue the vertical flaps, then the arch flaps, and finally the side flaps).

Here’s a picture of the closing of the ceiling, and a photo of the interior of the fuselage once the roof is finished.

After the cabin is finished, work starts in the cockpit. You can follow the instructions step by step, or work each piece separately. In the end the result will be the same.

First, I went from this:

To this:

And from this:

To this:

I confess I didn’t like much my work with the pilot seats. Not clean at all, and pieces were damaged too much in handling.

The fit of the seats is very tight, and it is even more so because of the cardstock. I had to trim a bit here and there to adjust for the thickness of cardstock. So be patient dealing with the seats.

And don’t forget a useful trick to get the shape of the backs right: use a cotton tip slightly damped in water to wet the paper, and a small rod to torture the paper until it gets the proper curve.

It definitely was not my day when cutting. The pedals were not anywhere near accurate or clean:

So I hid my mistakes with some silver ink.

In my defense I can argue that with those pedals we are talking about 0.5mm cardstock frames. Something that is difficult for me.

One more thing about the pedals: the upper part must be folded thrice in order to make a spacer (1mm folds). That can be a nightmare with 0.27mm cardstock. I decided to add instead 3 layers of cardstock to get the thickness.

The body of the cockpit is not difficult at all, but you must remember that you may need to trim a bit here and there to get everything fit properly. And if at some points the instructions look a bit unclear, don't worry: use your modeling instinct

Here’s a photo of the cockpit bulkhead as seen by the passengers (including the second extinguisher):

And now we can take a look inside through the door window.

Hmm… the door opens to reveal more details, like the hydraulic brake lever made with the help of a pin, a drop of glue and black paint.

And here are two more views of the cockpit.

The first major step of the build is complete with the attachment of the cockpit to the cabin. After this, work will start on the exterior of the plane.

Macro photos and good lighting provide interesting and detailed views. However they also reveal all the mistakes not seen by the naked eye

I’ve been absent these past weeks because I had to correct one little thing: the SCADTA logo on the fuselage. The logo is a stylized condor displayed over a landscape with a river and mountains.

I based my version of the logo on old timetables found at: http://www.timetableimages.com/ttimages/av2.htm
And I draw it with a full red background.

However, after an interview with a retired AVIANCA engineer who has a huge collection of SCADTA memorabilia and documentation, I found my version was wrong, and the correct logo used white color for the sky (not red). He assured me the colors were correct, except for the sky. Below you can see the difference. On the left my incorrect first version, and on the right the corrected version.

So I took the new file to the same copy shop where I printed the kit… only to find it had closed down. Too bad. So I went to other places to print the file… only to find that even laser printers differ a lot from each other, and at the end I got 3 different hues of grey from the same source file, not one even close to the original I had with the wrong logo.

Tired of that I just decided to come back home and use the original piece with wrongly colored logo. At least that way I preserve uniformity in the grey color of the aluminum skin. But it was “bye-bye accuracy”.

So let’s continue with the report, as close as possible to the original instructions.

The cockpit is not difficult, but it must be done with care because of the folds and cut-outs of the windows. If you downloaded the kit, you’ll find that in the digital restoration I provided extra grey part to be used as backing, so that the back of the cardstock doesn’t look white when seen through the windows.

That is probably a good option if you use thin cardstock. However, if the cardstock you use is a bit thick this may cause you unnecessary problems when folding. I found it was my case, so I just opted for painting the back of the cardstock with silver ink.

The transparent windows were made with the template provided in the kit. I just used white PVA to glue them. The seem to have glued well, but time will tell.

The cockpit is attached to the structures without problems. If you need to adjust something it will be very little.

I cut the windows of the skin, and pre-shaped it before glueing it. Always dry-test it before glueing it. Since the cut-outs of the windows align perfectly it is very easy to get the skins glued properly (don’t forget to previously glue a piece of acetate to simulate the passenger windows).

One small note: you may want to dry-test the fuselage skins *and* the cockpit before glueing, so that the cockpit side windows match better with the cutout of the fuselage skin. I did it, and used a pencil to trace the place where the cockpit should be, then glued it, and after dry I glued the skins.

Don’t pay attention to the silver paint. I brushed some to prevent any white part showing after the skins were attached, but in reality none of it showed.

After glueing the skins, I had a mildly unpleasant surprise: the top of the roof where the side skins meet was a bit too short. You can see there is a gap of almost 1mm. I believe it could be for a number of reasons:

- Cardstock too thick.
- Parts drawn a bit smaller than the original.
- An accident when modifying the part to eliminate the round cockpit window to convert it to a 5-AT-D.
- Glueing the cabin arch roof *before* the sides of the cabin roof.

Or it could be a combination of some or all of the above.

In any case that gap is now forever part of the model. Fortunately, it is a very forgiving model, and some mistakes can be made without affecting too much the appearance of the plane.

Now is time for the rear part of the fuselage. Here I would like to call the attention of anyone building this kit. When I cut the part and compared it to the original I found the one from the digital kit was smaller than the original. Not much, just 1mm or so. But it is a noticeable difference. I really don’t know how or why it happened. But it happened nonetheless. I offer my apologies for the mistake, and warn you to be prepared for some extra work.

The problem lies in the point where the rear fuselage structure is joined with the main structure (at the rear wall of the toilet). The rear structure lacks 1mm to be equal in width to the width of the toilet rear wall. This will never allow a good fit of the skins, and the gap (or “step”) will be awful.

I solved the problem by laminating 2 pieces of cardstock to each side of the rear structure, so that way the skins of it will have a more flushed contact with the cabin’s skins. You may need to trim the upper arched ribs a bit so that the skins fit properly at the bottom.

In my case I also had to add bits of paper and cardstock to fill the space between the two structures, so that they glued better. This part requires some work if you wish to have a good model with a good joint. But the result is really worth the effort (and I think more experienced modelers will get even better results).

In the end you’ll get a nice fuselage.

In my case it is a nice fuselage with an inaccurate logo.
(sorry for the improvised photo: the fuselage is already bigger than my working area, so I had to use my bed and a piece of cloth to get a decent photo... I really don't want to show how incredibly messy my small working area is .)

That’s all for today’s update. See you soon with the wings and stabilizer sections!

We continue with the building of this nice plane.

Rear stabilizer and rudder/fin parts are very easy. There’s nothing much to comment here. I just made holes to prepare them for the rigging.

The wings are easy, but as the rest of the model they need a little patience while the glue dries. Be careful to glue softly the wing skins in place, to avoid the spars to show through it.

When glueing the center section skin I added a couple of extra fill cardboards to get an even straighter surface. But that’s optional.

As you can see, I glued the control cables at this stage. They are supposed to be glued later (almost finishing the model) but I prefer to add them now, to be able to anchor them from the inside.

And on the top wing section, where the control cables exit the wing, I practiced a hole, and with the help of a little piece of paper I glued another set of threads on each hole. This way it looks a bit more realistic

Here’s the part where the wing joins the top fuselage. Great fitting.

Now a more general view:

Wing assembled to fuselage, front view:

Now is time for a critical part of the building: the engine pods/landing gear sections. But that will be for another day.

See you soon!!

It’s been a long time since the last update.

Let’s see..

In this time I printed the “decals” and corrected the logo on the fuselage.

I also added ventilation openings to the nose. The kit simulates them only with drawings on the nose. But I printed small trapezoidal parts and after careful folding and glueing the openings were done. Here’s a photo just before I finished the right side of the nose.

Engine pods are a critical part. If you are building this kit be ready for a challenge to your patience.

The main axis of the pods must be parallel to both the fuselage and the wings. My recommendations are:

- build one pod at a time (the instructions already say that).
- the seams of the struts all face backwards.
- some trimming and adjusting in the struts may be needed to align properly the pods.
- use cyanoacrilate glue to set everything in place once you get everything in shape.
- consult carefully the instructions and reference photos to see where everything goes.

As you can see, I also added new ventilation openings in the pods.

Now... although I don’t usually show scale before I finished, someone at the Spanish forum asked me to do it. So here’s a photo of the plane with a CD and my cell phone so you can get an idea of how big it is.

I’m working on the wheels and landing gear struts right now. Photos soon! (I hope).

Work continues with the landing gear.

The attached photos show the classic constructions of laminated wheels: sandwiched layers of cardstock, then sanding, and more sanding, and more sanding.

I made a jig to get the correct rounded profile of the pneumatic.

The kit is originally intended for fixed wheels. But you know that I like movable wheels, so I used a pin to create an axle and leave the wheels rotate. They don’t look so great in the photos, but hopefully I will take better photos for next time to show the landing struts and the finished gear.

This week’s update with 15 new photos

First, you can see the assembly of the pods/struts/wheels with the landing gear supports, all attached to the wings. If something is made wrong here, it will show noticeably. Alignment is very precise, and the lower diagonal struts will tell you if you made it right or wrong.

You can notice I used a folded piece of cardstock to fill the bottom of the fuselage. This was added to prevent the lower and side skins to collapse. It was a good idea because it allowed the bottom fuselage skin to glue easily, and there was very little trimming needed.

I used a couple of wires inside the lower struts to give some strength to the structure, but apparently it doesn’t need much metallic help.

Now the plane can sit on the wheels.

Bottom and top views, with rear part and wing tips attached.

This is the nose with control horns and control cables attached. It was a wonderful idea to glue the cables to the wings early in the process, since attaching the individual threads to the horns and to the bottom of the wings is very difficult.

Front view of the rear section, showing tail plane, rudder, struts, and control cables.

Rear view of the same section.
If you are building this kit, I strongly recommend that you glue the control horns to the rudder and stabilizer before attaching those parts to the fuselage.

Notice the rear light in the tail, not a part in the original kit, but the real Cartagena had it. Maybe I made it too long.

Wing tips were attached. I really didn’t feel comfortable glueing them. They were a bit difficult for me. Probably a small misalignment in the wing spars was the cause. So patience was needed.

Two cheap jewelry beads were used to simulate the port and starboard lights.

Detail of the rear light. It was also made with a small plastic jewelry bead. I crushed the paper when handling.

This light, as well as the wingtip lights look really fine if you don’t use macro-eyes

Lower rear section, with the tail wheel. The wheel was made with the same technique of the main gear. It is also movable thanks to a hidden thin copper wire used as axle.

Details of the fairleads. I thought it was cute to add them.

After all this, now is time to face the most feared part of the model: the engines. Three engines, 27 cylinders… I will rest for a couple of days before staring them.

This is to prove that I’m still working on this model.

I changed the tail light. Now it is 40% shorter, and looks a lot better.

I also tried to save the threads by applying some glue. It helped, but not much. Next time I will prepare the threads before assembly. Or use another kind of thread.

I also installed the rail under the wing that was used to open the wing cargo hatch. This part is not included in the kit, so it was scratch-built. Very easy to make.

And although the landing lights are the last step in the book, I decided to add them now. I used a transparency to simulate the glass, another small plastic bead to simulate the bulb, and a printed simple background to complete the effect.

Now is time for the engines. In the following photo you can see all the three engines. The one on the left is complete. The one in the middle is in process, and the right one has not been started yet.

This is a close-up of the unbuilt engine.

Here is how it starts to take shape.

And here it is complete. I was going to use the original parts to make the manifold exhaust ring, but I lost one of them. So I had to improvise with a small rubber hose painted silver to simulate it. Of course will make the same in all three engines.

Now all that’s left is to finish the engines, and add small details.

See you soon!
(I hope)

After installing the door with handle, the jump seat, the engines in place with the NACA rings and the exhaust pipes, there are no more parts left in the box.

Now I only have to wait for good weather and look for a table big enough to place this bird at take some decent general photos.

My next post will include final photos and my final report/opinions/tips about this kit.

So we had a nice cloudy day today, perfect to take some photos.

This photos are a bit edited to erase some background, and are balanced to show more of the true colors of the plane.

Since most of the details were discussed during the process, I won’t comment much. Just enjoy the images.

More photos

What’s this?
Two Tri-Motors?

Yes. It’s two of them, let’s have a closer look.

Now you know my secret: I built two “Cartagenas”. The white one was a printing error. I didn’t want to trash the printed pages so I decided to use it as test. I first built the test plane little by little. And as I understood the tricks of the parts I built the grey one correcting mistakes and improving the details.

The white Tri-Motor looks sloppy, badly build, with lots of issues. But it helped me a lot to understand the model and to face the challenges properly.

And I also decided to cut the sides open so that the interior of the cockpit and of the passenger cabin could be seen. The toilet can also be seen with all the detail you saw

So this is it! The Ford Tri-motor designed by Peter A. Zorn Jr. in 1982. Digitally restored in 2011, and painted in the colors of the Colombian airline SCADTA in 2012

Comments

This is a beautiful kit, from a time when paper kits were drawn by hand. It may look a bit simple by today standards, and some may say that it is not a perfect replica of a Ford Tri-Motor in certain details. But the truth is that the result is impressive. Besides, the shape and proportions are very accurate. The solutions to some volumes and elements of the plane are very clever and allow getting a good representation of the real thing by means of easy assemblies. If a modeler wants to add detail, there is plenty of room to do it. There are just a couple of difficult spots, but nothing serious. It is recommended that you think beforehand where to use cyanocrilate to give more strength to certain parts. Also, plan the whole process before starting.

The fitting of the parts is good. Take into account the following: the digital version of the kit was re-drawn based on scans of the original printed book (which was painstakingly drawn by hand). So, some small differences were unavoidable in the whole process. As I cut the parts I noticed the new digital version had small differences of up to 1mm compared to the original parts. This is a minor problem, but it may affect the perfect fitting of some parts. So be careful and always test the parts before glueing. Trim if necessary; add shims of paper when needed, and glue carefully. If you exercise patience, good judgment and follow your modeling instinct you will be able to make a very good paper model of this classic plane.

Remember that you can download the Tri-Motor kit for free from http://www.papermodelers.com/f…s.php?do=file&id=1080
It comes in 11 different liveries including American Airlines, TAT, Grand Canyon, TWA “City of Philadelphia”, Indiana Jones’ “Lao Che” transport, and some more.

My gratitude goes to all the people who have commented in this thread, not only here but in other forums too. The reception this model has had makes me happy. And the support of everyone is treasured in my heart. Thanks a lot for your comments, suggestions, and advices.

I shared this build in other forums, and I wish to thank them all. You can find the same thread there.

So, thanks a lot to all of you. And to all the people at:

Paper Modelers http://www.papermodelers.com
Zealot http://www.zealot.com
Kartonbau http://www.kartonbau.de
Maquetas y Modelismo en papel: http://maquetasenpapel.mforos.com/
Papercraft America: http://papercraft.mforos.com/
Mequetas de Papel: http://www.maquetasdepapel.com.ar/
Swanny’s Models: http://www.swannysmodels.com/yabb2/YaBB.pl
IPMS Bogota: http://www.network54.com/Forum/219512/

And last, but definitely not the least, thanks a lot to Peter for designing this beautiful kit, and for allowing it to be distributed for free. My deep gratitude.

See you in the next build!!!!!

Rubén Andrés.

Thanks a lot for all your kind words, and for your support.

It was really a pleasure to work on Peter's model. I enjoyed the digitalization process, and then building this kit.

I prepared a video slideshow showing the most important photos of the thread. You can watch it on youtube here:

http://www.youtube.com/watch?v=V3a7o92fUOU