Fat Man (F31) at 1/24

[nando]

Thanks Darwin, I try to be as much accurate as i can in my project, while this makes slow my work: I discovered that I began to work on Fat Man on may , near five months it's a long journey.

Originally Posted by rjm

Just bought a copy of "The First War of Physics" by Jim Baggott. Color picture
of "Fat Man" on the cover, and A black & white picture of the first "Fat Man"
that was used in the Trinity test. Lot's of spaghetti on the outside of that one!

I was impressed me too by that "hairy" picture of the Gadget and I dug deeper.
The long wires that surround the sphere are the cables that connected the X-Unit to the 32 detonators of the bomb.
The issue was the triggering synchronization for generate a spherical compressing wave, so the wires must have the same lenght.
Many of them are too long and hence it derives the hairy look.

There is a little-known episode about the troubles that this wiring generated on Fat Man.
In the rush to complete the bomb, the firing unit cable was installed backwards, requiring Ensign Bernard J. O'Keefe to cut the connectors and reinstall them at the very last minute.
This is one of many trouble that have marked the history of the mounting of F-31.

Here some references:

About the need of long but equal wires


About the X-Unit : the LOW IMPEDANCE SWITCH, to synchronize the trigger


An extract of the book "Nuclear Dawn: The Atomic Bomb, from the Manhattan Project to the Cold War" about Tinian episode.


The assembly of Fat Man at Tinian




An interesting story.

Best, Nando

[nando]

Just a couple of pictures tonight, about the rear support of the wheels.




Best, Nando

[Jinrai Butai]

I am impressed following your project from the start. The 3d modelling was interesting, due, that you made it on a software that is easy to use, at least for me, that I am not very skilled in this kind of software and I am new in the papermodelling. The process to pass the virtual model into a physical was another interesting part of your project, that showed me a thing that I had not keep in mind: The patience. Test after test was done to reach the desire result, every minute you invested, worth it. It is a great model that prompted me to return to my first project and think in other similar to yours (WW2 rockets), and showed me those particular bombs that I had never seen graphically on my world history books in the High School. I hope soon show you something and also I hope to understand my comment, I did my best to wrote it in english .

And as I wrote before, it's a great model.

Congratulations and I´ll wait the end of the project with the carrying base.

[nando]

Thank You Jinrai Butai for your kind words and no worry for your english: I have some problem with the language me too. My aim is to use softwares that are cheap or free, but You have to pay a cost having many passages and adjustements to reach an acceptable final result. And more, as modelers, we have the madness to render at the best the subject that we reproduce. But this is my and our sickness
I would like to see your project (ww2 german missiles). One of the first paper models that I did was the Currell's V2: an outstanding model!


Now back to building the trailer: the forward axis and his support.









The pivots



and a first dry fit



Next the tiller

Best, Nando

[nando]

Here the tiller parts and how they come together.





And at last the model completed.








Now I have to edit the final release and assemble the instructions.

But I have to examine again the pictures I have collected to verify if there is some detail that I forgot along the way.

Best, Nando

[thorst]

Nando, it looks spectacular! Absolutely round and smooth the bomb's body, the trailer totally clean... Congratulations!

Thorsten

[Darwin]

Bravo!!! Masterful work, Nando. I can't wait for the release.

[nando]

Thank You Thorsten & Darwin, your constant support has been important to me.
I'm busy right now on writing the instructions. Here an example of the assembly diagrams i'm working on.



Best, Nando

[JohnM]

Have you had time to make yours yet Nando? If not, watch out for part 67. Do not glue the bits that go between the legs until after you've completed the legs. Just fold them back out of the way. You will need the hole to get your fingers through in order to press down on the leg tabs.

Johnny.

[nando]

Thank you Johnny for the hint. Scrat was suspended after I did the nose but I will restart the build when I ended the Fat Man. In the mean time I added a weird detail: a can of paint.
I noted that the structure of the trail is weak at the joint of the forward support and it tends to bend slightly under the weight of the bomb (sig!). May be we can think to modify the design or stiffen the bars with cardboard, or metallic wire, but it's to late.
I tought to sustain the forward part with a strut, but it was strange a support under the trailer. But why not a can of paint? It's better to hide the strut, showing it, in the shape of an object that is plausible.
Here some picture.




Best, Nando