Heavy Mod - 1/18 21st Century Toys P-47D Razorback

[richdlc]

really innovative approach. The end result / original parts are like chalk and cheese, night and day. Finished model will be awesome!

[Dan Paxton]

Simply stunning work sir.....almost expect it to turn over and fire up!

 

   

[brahman104]

Jay that exhaust collector ring is insanely good, how on earth did you manage to file it down to such an accurate cross section? I would have had flat spots and divots all over it if I did it!

 

The two engines side by side though - that alone says so much more than anything that could be written. 

 

I don't suppose you'd like to build 4 x R-3350's for me for a future project would you?

 

Cheers,

 

Craig 

[JayW]

Got good complements on the engine - thank you very much all.  Oh, to start over - I'd do some things differently.  

 

I am now at work on the two cowl rings and the engine mount bulkhead (which in real life is the a thin gage semi-full fuselage frame called the "preheater assembly and baffle"), not an engine mount at all.  But for this model it serves as the engine mount, and a good one.  The cowl rings have fittings which attach to the cylinder head valve covers - at every one of them for the forward ring, and at 14 of them for the aft ring.  This work more than anything to date shows the inaccuracies that crept into the engine build.  Also - in real life there are small detailed parts which incorporate a universal joint of sorts at each attachment location - something I just cannot duplicate even at this scale.  So the going is slow, and sometimes disappointing.  Soon as the work is done, or semi-done, I will post.  Very challenging.  Partly because the fuselage is still in two halves and must remain that way until the cockpit is done, and a few other details.  That's alot of work for sure (the cockpit alone will be a months long project).  So to do some of this engine compartment work I have to securely tape the fuselage halves together and make believe it is all glued together.  I could wait on the engine compartment, but I am kinda on a roll and do not want to ruin the momentum, or forget my good ideas.  Will post soon to show you all what I mean.  BTW - who was it who suggested an open engine compartment???!!!

Edited June 18, 2017 by JayW

[JayW]

Let me show you some pictures of my progress on the cowl rings and the pre-heater assembly (aka engine mount).  These are the three important structural members for the engine compartment which will be visible at least to some extent, especially with cowls panels off.  First, the pre-heater.  I will be frank - I don't know what a "pre-heater" is really.  If any of you know, please enlighten me.  At any rate, for my purposes, it is a bulkhead of sorts that wraps itself around the engine mount ring, and provides an aerodynamic surface for air flowing through the front of the cowl to escape through the cowl flaps.  Here is an excellent picture of an engine with the pre-heater:

 

 

Note in that picture, the actual engine mount is a welded truss-works which has many struts and a ring mount.  The struts are attached to a blue stand (which subs for a heavy bulkhead on the actual airplane).  The pre-heater is that big unpainted light gage partially completed fairing behind the engine.  But I am not going to model that truss-works, so how to mount the engine.  Well - I am going to mount it to the pre-heater.  Here is my pre-heater:

 

 

 

It consists of a lathe turned piece meant to simulate the lip that wraps around the engine mount ring, the engine mount ring itself (you  have seen it in previous posts), and a .12 thick plate that will serve as the engine mount.  It is re-enforced on its backside with some ribs made of heavy gage plastic (this engine is really heavy!).  The periphery is a bit oversize, and will stay that way until such time as I final install the engine to the fuselage.  To do that the fuselage halves must be bonded together, and to do that the cockpit must be completed, as well as some other stuff.  So that is a ways down the road.  Also note the sloppy fillet done by simply slathering a bunch of epoxy in the corner.  Compare to the sleek aero-shaped fillet in the previous picture.  Matters not - this feature is virtually unseen with cowl flaps installed (even kicked open like mine will be).

 

So the original kit installs the engine on a bulkhead just forward of the cowl flaps, like this:

 

 

That black bulkhead will be useful to me as the aft cowling ring.  You'll see.  But my engine will be mounted to a surface aft of the cowl flaps (the preheater):

 

 

And that my friends is why I had to make the intake and exhaust manifolds.  Common - admit it.  That's cool.  I think so anyway.

 

OK, now for the aft cowl ring.  This thing has two functions in real life, and also on my 1/18 rendition:  One, to provide support for the engine cowling panels.  To do this the ring is attached to the engine itself, in 14 places, with special fittings.  And two - to provide a mounting surface for the cowl flap hinge fittings.  The aforementioned kit bulkhead is perfectly contoured (and almost perfectly placed) to serve as this aft cowl ring.  So I really butchered it while maintaining the outer shape:

 

 

Here it is in a little better shape:

 

 

You see the aft face, and those little spacer plates will serve as locators for the cowl flap hinges later on when I get to them.  They will be uber-difficult to do accurately.  The cowl flaps are such a trademark part of the Thunderbolt.

 

And in this picture you see the aft ring attached to the engine with all 14 attach fittings.  I will not focus in on them yet because I am not that happy with them.  I am going to try to improve those details some, and show them off next post perhaps.

 

 

 

You also see there the all important (and major PITA) forward cowl ring (partially finished).  All important because it is readily visible while peering into the cowl opening.  I believe most P-47 model manufacturers do not include cowl rings.  Anyway, I did not have the benefit of an already existing bulkhead for this part, so I made one from scratch.  It is in process, and next post I will show it completed.  A real one, BTW, looks like this:

 

 

Also next post you will see the oil coolers attached to the pre-heater.  And that my friends will be basically it for the engine compartment, until it is all final installed to a completed fuselage, at which time I will tidy it up, final trim the periphery of the pre-heater, and fab and install the cowl flaps.  Until then it gathers dust.

 

Take care. 

Edited June 25, 2017 by JayW

[Guest]

VERY cool !! Harv

[Citadelgrad]

I am searching among my superlatives, amd apologize that all i have is Wow.

[Joel_W]

Unbelievable  I've never seen engine detailing taken to this level before. Then again, I've never seen a 1/18 Jug. Your build is one for the books for sure.

 

Joel

[Jim Barry]

You are really pushing the boundaries. Way to go!

[JayW]

Well as I am sure all of you are grappling with this, photobucket has screwed us.  Not sure what I will do now.  Another service I suppose.  Any good ideas? 

[Shawn M]

Flickr, I've used it for ages and love it

[Jim Barry]

After I dried all my tears I went with imageshack. $20 a year. I'm very happy (no ads and fast upload!) Some are loving smugmug. To fix the past, I decided to restart my active build threads (my only threads in my case) anew and post greatest hits of the build to date and then move on from there. It was not fun but honestly only took an hour or so. Perhaps a thread clean up was in order anyway.

[JayW]

Hello!!!! Is anybody out there?  It's been about 6 months since I added anything to this post.  Ever since the Photobucket fiasco.  Since then I have just forgotten about update posts, in frustration, and in ignorance about what to do.  But I did not stop working on the Thunderbolt.  And now, I am going to try out Imgur, and show a picture of the toy cockpit which is in the process of being entirely replaced with a scratch built one: 

 

https://imgur.com/N3bzHCD

[JayW]

That is not what I wanted.  Will try something else:

 

 

Wow - that's big.  Anyway what you see is a typical rendition of a model cockpit.  I intend to build an authentic looking cockpit for a P-47D-30.  Here goes.

Edited January 23, 2018 by JayW

[JayW]

First one must make a forward and aft bulkhead, like this:

 

 

Edited January 23, 2018 by JayW