Fokker FG-2 - Congrès 2017 Vauville

[Walter]

Hi Vincent,

...very interesting project - I will follow!

3784 actions.... and nobody can see this after covering....

So - I would suggest - make one ore two more for demonstration...

...hope to meet you in vauville



Walter

[bocorvin]

Hi Walter,

Thanks for the . Luckily you can see the ribs at the "Expo fuselage!", but the main reason is the translucentcy of the wings, with massive ribs they would look very different (I think )

Vincent

[Mad Doc]

Hallo Vincent!!!!
Endlich habe ich es geschafft mir Deinen Bericht anzusehen, was für eine schöne Arbeit!!!
Ich bin sehr gespannt auf Deinen weiteren Fortschritt, liebe Grüße,

Christian

[bocorvin]

Hello everyone,

Back from Polsa and our holyday I started again with the wings.
I liked to make the wingspars thinner, 4mm instead of the 8mm as planned, with internal crossbracing, as I discovered on the photo (with the FG 2 on crates). First I made a full size drawing of the wing.


I made mainspars from 4 X 4 mm with a ply webb and vertical from 3 X 2mm.




When I got them finished they appeared to be very flimsy. I can imagine, that combined with the crossbracing it would be just strong enough, but very vulnerable. In the end I decided to go back to a bigger spar. Because the wing must not be stiff in torsion, I opted for 4 X 8 mm top and bottom with a single 1 mm ply webb.

This was much better! I also choosed to have the wing divided, in one piece is too impractical. As wing joiner for the main spar I took a steel strip 10 X 1 mm and for the rear spar a 3 mm steel rod. In the centre part of the wing are a lot of attachments; on top the struts with fuselage, and at the bottom the landing skid. I took M 4 bolts bedded in epoxy with filler and some carbon reinforcement. I greased the M 4 bolts a bit, so I could take them out when the epoxy was set.







(The balsa at the ends is just to prevent the epoxy for flowing out, it can be taken away easily.)



All the stuff needed for the wings..

The central lower part of the wing.

Putting all the ribs on the spars, a very quick job compared with making of the ribs itself!

One wing! To my big relief it was in horizontal plane sufficient stiff and stiff enough (for a biplane) vertically.

Moment of truth: the wing is easily warped!

Next thing is the upper wing.
To be continued.
Vincent.

[VincentB]

Encore un sacré travail de fait, bravo Vincent

[michel]

belle structure, c'est quoi comme profil ?

Michel

[bocorvin]

Merci Vincent et Michel pour les comments encouragieus!
Le profil est Eppler E174.
The weight of the wings at this moment is 640 grams, I think the whole plane will be about 3000 to 3500 gramms. Gives a wingload of 22- 26 gr/dm.

Vincent

[bocorvin]

Hello everyone,

Erstens, Christian , danke fur dir kommentar, es war schon lange da, befor wir zu hause waren, Ich war vergessen darauf zu reagieren.

This week I assembled the top wing,




I'will make the internal crossbracing only cosmetic, because I made the girders a bit heavier.



Top and bottom wing together;




Laminated the wingtips out of two 2mm X 3mm spruce .


Both wings



Now I am going to finish the wings and start with the fuselage.

To be continued.

[Frédéric]

Salut Vincent !

C'est magnifique ! Très joli travail !


Amicalement
Frédéric

[michel]

Magnifique structure,

Michel

[bocorvin]

Merci Frederic et Michel! It is very encouraging
I am waiting for the tubes and puzzling about the fuselage, how did Fokker connect the wood with the tubes etc?

Vincent.

[VincentB]

Que fais tu exactement en tube? tout le fuselage avec les haubans des ailes et les poutres arrières qui maintiennent l'empennage? ou seulement la partie avant du fuselage qui est entoilée?

[bocorvin]

Bonjour Vincent,
Excuse moi, je continue en Anglais, the tailboom, horizontal and vertical stabilizers, wing struts, struts for the skid and the tubing to support the skin of the nacelle are of tube.
The " A " which you can see on the view from above on my plans is from wood, but I think it is interconnected with metal fastenings. In the coming week I am going to visit the "Aviodrome " (a museum) to have a close look of the Fokker Spin (spider) which is displayed there. The Spin is also a bit of hybrid construction, timber with metal. I hope that I understand a bit more of his , don't know how to say, construction pattern? just the way he worked with wood & metal. I ordered the tubes at "tubos capilares", very nice service, hope to get them on short notice.

Vincent.

[VincentB]

Pour des connexions tubes/bois, tu peux braser une tôle de 1mm et boulonner. Le bois peut aussi rentrer dans un tube si ce n'est pas une partie soumise à des efforts.

[bocorvin]

Je ne comprends pas, helas, je ne connais pas le mot "boulonner".
On one of the photo's you can see (guess) how support tubes are fastened to the skid, it looks a bit like this.
The tubes are silver soldered to the "U "plate.


The bolt is M2 , that would be M10 true scale. I guess he connected those quite big timber parts with metal plates and bolts. Its only educated guessing

Vincent

[VincentB]

[bocorvin]

Bonyour a tous,

I started with the fuselage, first the nacelle. That is built of wood and steel. I tried to make a drawing based on the existing plans, photo's, thinking and guessing!




To get a better idea how fokker bolted all that wood together I visited the Aviodrome, the Dutch aircraft museum. The plane I like to see was the Spin (Spider).I was allowed to make photo's of details (thank you!). There is a snag, this was a replica of a replica, I think the basic construction of the fuselage was 90% correct.










As you can see, rather big steel profiles and big bholts are used, I'll try to keep this in mind!
I glued the wooden frame, first out of 10mm X 10mm spruce, but looking at some photo's of the original I changed it 8mmX 8mm.

Laminated the skid, first 3 layers 3mm X 8mm spruce, later one extra layer at the bottom. I drenched the spruce in boiling water before bending. Clamped it without glue together


and put very thin cyano on it, no mess!
Now I had to start with the metalwork. I ordered stainless steel tubes at "tubos capillares", as recommended on the forum and within a couple of days I received a 2m long package, very good service!

I made the supports for the skids an the piece of metal at the nose to connect the 'nose'of the 'A' and later the tubing of the nacelle. It was long ago I used silver solder and it took some time to get used to it.

After using a bigger torch thing went better, but it was sometimes difficult to keep all the parts correctly placed!






Later it will be bolted with M2 trough the wood.

Just to get a better idea to make the tubing of the nacelle, the placing of the rc equipment and the pilots I put it temporary together.

Never built someting like this
My idea is next to make the tubing of the nacelle and a bit later detailing the wooden structure. I am not used in constructing wood with metal and there is a lot of thinking and guessing in it!

to be continued.

[CHAUSSEBOURG]

Very good building and many thanks for all the détails!
Pierre

[de Schaetzen Harold]

Prachtig! Zeer indrukwekkend. Alles is goed nagedacht.
Doe zo voort.
Harold

[bocorvin]

Thank you Pierre for your nice comments and Harold hartelijk bedankt en inderdaad ik moet me soms suf denken, maar dat maakt dit soort projecten spannend!

Vincent