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

[airscale]

 And because I am so proud of that detail, here's a pic of it:

 

 

 

 

..and you should be proud Jay - that 'pit is a work of art - loving what you are doing with these kits - really special work..

 

Peter

[JayW]

Quite a while back I gathered my courage and my saw, and cut off the beautiful engine cowlings and cowl flaps:

 

Before -

 

 

And after:

 

 

Scary.  But I did it for two reasons.  One, of course I wanted to display the engine.  And two, I wanted to have more realistic cowl flaps, in an open position.  Now at last, it became time to give the eagle back her cowl flaps.

 

Cowl flaps on radial engine aircraft are mounted on the aft cowl ring which is in turn mounted to the aft row of cylinders of the engine:

 

  

 

So I had to have an aft cowl ring.  Recall that this toy just happened to have an engine mount bulkhead that was perfectly aligned with what would be the aft cowl ring.  So after much mangling and trimming, it indeed became the aft cowl ring:

 

 

 

That was many months ago.  Recall the twelve little plastic blocks radially located on the aft surface of the ring are for locating cowl flap supports.

 

So to begin my work, I had to first accurately mount the cowling to provide the contour the cowl flaps must match.  And to do that, I needed to restore the thin slices of material sawed away when I removed the cowling (about 0.01 inch thick).  Also, I needed to provide a means of securing the cowling accurately in place.  I did this with little metal pins and matching holes.  Here:

 

 

 

Note the thin strips of plastic sheet, and the four 0.032 brass pins.  That doesn't look like a big deal, but it is.  I was entirely unsure I could get the cowling to look good (like it had not been sawed away!).  And this worked.  Next post, when I really clean it up, you will see.

 

The cowl flaps are simply 0.015 inch thick sheet with a little frame behind the sheet:

 

 

Each frame was glued to the cowl ring:

 

 

Note the push rod.  With the frame mounted first, I could fit the flap panel itself to match the little tape template you see on the aft edge of the cowling.  Do it twelve times and you get this:

 

 

 

 

The reason, of course, why one goes through the trouble of making cowl flap frames and pushrods, and the engine exhaust manifold, is because they can be seen if you look hard enough!

 

 

I feel a great sense of relief.  I guess I was inwardly worried the cowl and cowl flaps would not go well.  But they worked out 90% plus to my satisfaction.  Now, I have some fine tuning work - touch up etc.  The bottom edges of the cowling need some touch-up work for example.  Then I believe it is back to the canopy which needs an arch and alot of little parts for the emergency jettison stuff.  See you then.  

Edited June 4, 2018 by JayW

[Out2gtcha]

VERY cool!  Great work on the cowl and flaps

[Shawn M]

man that looks great

[NukerDan]

Jay,

Found another miniature chain, this one from LSP sponsor MDC:

 

http://www.modeldesignconstruction.co.uk/mall/productpage.cfm/ModelDesignConstruction/_MDCDT05/54274/41%20links%2Finch%20Chain%200.5m

[JayW]

Nuker!!  Or is it Dan?

 

My arithmetic says that chain is just the right size.  How about that?  I think I'll order one, comes from England so I'll have to wait some.  Thanks for the tip!

[NukerDan]

Nuker!!  Or is it Dan?

 

My arithmetic says that chain is just the right size.  How about that?  I think I'll order one, comes from England so I'll have to wait some.  Thanks for the tip!

It's Dan. Glad to be of help, can't wait to see what it looks like!

[JayW]

OK - the canopy was a little more involved than I thought.  But first, the engine cowling was touched up a bit.  Here it is pretty much in final condition:

 

  

 

Zoom!!

 

The canopy provided, as I mentioned already, is a little too big.  And I have to live with that.  It was kinda pretty, but lacked a lot of detail that ought to be there at this scale.  A reminder of what the windshield and canopy looked like originally:

 

 

Here is what I did to it:

 

1.  Reshaped the canopy frame along the sides - this was really hard.  I basically masked the shape I wanted, used 2-part epoxy to fill in the area a bit with a "fillet", and hoped for the best.  It's not super-clean but it's better than it was.  

2.  Added many drill starts to depict fasteners.

3.  Added scribe lines for butt joints to canopy frame skins.

4.  Made and installed a canopy arch from simple plastic sheet.

5.  Made and installed the emergency jettison mechanism - pushrods, bellcranks, bellcrank support fittings (simple plastic stock).

6.  Made and installed the forward bow with the jettison handle and cables (fishing wire).

7.  Made and installed the rubber blade seal which runs along the periphery of the canopy frame (.005 plastic sheet).

8.  Lotsa painting.

 

The key here is to do all this work without ruining the clear plastic.  I was somewhat successful doing this.  Future floor polish gave the canopy glass a good sheen and minimized any scratches or other mars.  Pictures:

 

  

 

 

Those pics above are the canopy arch which of course is there to provide not only stiffening for the canopy frame but a support location for the aft set of track rollers.  The P-51 has a similar arch but it doesn't act as a roller support.  Also, unlike the P-51, it has a linkage hanging off it for the emergency jettison mechanism.  Pull on the red handle at the forward canopy frame, and cables rotate a crank arm, which pulls on the rods you see there, and that acts to release a pin in the fitting on the arch that supports the rollers.  Which allows the fitting to separate from the canopy.  The same mechanism of course unhooks the two forward rollers; then the canopy flies away and the poor defeated pilot can punch out!

 

This picture shows the release mechanism in its entirety, including the forward bow frame with red release handle on the upper right region of the bow:

 

  

 

Many inaccuracies at the two lower ends of the frame.  But I wanted to save the snap-in feature of the canopy which was provided on the original part.  That feature unfortunately doesn't look at all like what is really in there.

 

A close-up of the jettison handle from the outside:

 

 

And the finished canopy assembly:

 

 

Note the rendition of a rubber blade seal along the lower edge.  This needed to be there to look accurate.  Although - some museum P-47 bubbletops don't have it - probably because it rotted away or was torn off....  All this thing lacks is a couple of decals (later).

 

And mounted on the fuselage:

 

 

It doesn't fit real well - it sits up a tad proud, even without the blade seals.  I can push it down with my hand, but I don't really know how to get it more snug without just gluing it in place.  But I want to display it with canopy open too.  Will continue to think on this...

 

More:

 

 

 

 

I await the arrival of the little tiny chain that will go between the rails on the aft canopy track.  That will finish it off.

 

So what you see here is perhaps the most egregious fault of this model - the windshield and canopy being too tall by a good bit (maybe 10% or so).  It means a steeper angle on the windshield, and a wider more "bubbly" canopy.  I have gotten used to it.  But real P-47's have windshields and canopies that are smaller and more streamlined.  So you might notice more than me.  I sought to just make the parts as realistic as I know how and let the rest go.

 

Next on the docket is the Curtis Electric paddle blade propeller.  You know, the one where I had to resin mold one of the blades quite a while back.  Fun!  I'll show it to you next post.  Thanks for looking in! 

Edited June 17, 2018 by JayW

[Gazzas]

Wow, what stunning work!  I missed the update with the cowling flaps, and have to say I am totally impressed!

 

Gaz

[JayW]

Please recall some time ago, I purchased the bubble top Thunderbolt via E-bay, and it came with imperfections, the most challenging of which was a missing prop blade:

 

 

Those who have followed this entire build to date know that I struggled to make a resin molded copy, and eventually got one I could work with:

 

 

This part has been sitting around forever waiting for me to get going on the propeller.  And now it has finally come.  

 

Because I needed a master to create the molded part, I had to remove one of the blades from the hub.  And since i wanted to clean up the hub some, I decided to remove the remaining two blades.  They would all get root shafts (.25 inch diameter tube) in order to re-attach to the hub, a fresh coat of paint, and new decals.

 

Reassembly of the prop required me to create a jig of sorts to make sure the blades were all oriented at the same angle, and also square with each other:

 

 

 

This was very straight forward.

 

Here are the decals I made, also straight forward:

 

 

The Curtiss Electric emblems were obtained from the 368th Fighter Group website - just did a snip of the photo.  Note the black background for the serial number stuff.  Yellow doesn't come out well on clear decal paper - it's too light.  So I have to do it on white decal paper, an d create a background the same color as the part the decal is to sit on.  And hope it matches well.  In this case - it'll do I guess.  See for yourself:

 

  

 

Don't know if the picture makes it evident - but this is a BIG propeller!

 

Some shots of it on the airplane (have been waiting a long time to do this):

 

 

 

 

This last image is a close-up (shows all the flaws!), to show the electrical brush housing on the prop shaft, right behind the hub:

 

 

Am special proud of this, as I think this is not ordinarily modeled, because manufacturers do not understand (IMO) that it is a feature of the Curtiss Electric equipped aircraft, and not the Hamilton Standard equipped aircraft.  They might give you the option of either prop, but do not include the brush assembly.  

 

Think I will do some decals for the fuselage next, and then put it up in a safe place.  Will hold off on the centerline bomb shackles because they are sure to break off until this thing is on its landing gear.  Then....not sure.  But probably the aft fuselage and tail feathers. 

 

Question for anyone who cares to chime in - should I make the tail gear strut components without the canvas cover, which is a ton of work, or should I do a canvas cover (which will save that ton of work)?  I would like to represent the wartime config as it really was, and I am not sure if the units kept the canvas cover in there.  I think they probably did.      

Edited June 20, 2018 by JayW

[Gazzas]

Really love all of the attention to detail you're paying here, Jay.  It really looks special!

 

Gaz

[JayW]

"Question for anyone who cares to chime in - should I make the tail gear strut components without the canvas cover, which is a ton of work, or should I do a canvas cover (which will save that ton of work)?  I would like to represent the wartime config as it really was, and I am not sure if the units kept the canvas cover in there.  I think they probably did."

 

Well - that's what I said.  However, anyone familiar with the leather (not canvas) boot and shield assembly that come with the tail gear?  Wow!  What a complicated mess.  I have no idea how to model it.  The drawings are also hard to read, and I cannot find much in the way of pictures.  Therefore, I will embark on modelling the tail gear yoke, and a good bit of all the clap trap associated with it.  It's alot of stuff, but at least it's within my capabilities, and the drawings are great.  Stay tuned.  Should be fun.      

[Gazzas]

Jay,

    After reading your question yesterday, I went looking for pics of the tailwheel to satisfy my own curiosity.  There just wasn't much to see as pics of the real thing are from a bad angle, or have too little light to be seen.  The only cover I saw was on a model.  Other pics of non-models were useless.

 

The only thing I can offer is the opinion that the cover was there to keep dirt out of a complex mechanism that required lubrication.  I can't see how any maintenance guy would have left it off on purpose. 

 

Best of luck,

 

Gaz

[JayW]

Am still thinking on this Gaz.  If I can decipher the engineering drawings better, I might take a crack at it.  After all, most of the stuff is made from leather which starts out flat and gets stitched into shape.  Seems as if, at least in theory, I could get something to simulate the fabric even if its paper or some fine cloth, I could cut it to shape per drawings.  Here is the assembly drawing of the dust pan and boot: 

 

  

 

 

And a picture from the parts catalog:

 

 

Note there are three components to it - a couple of metallic dust pans that mount below the tail LG yoke, and roundish bag (or "boot") that hangs off a tube in the fuselage, and two "shields" that seem to wrap around the two arms of the yoke.  They all attach to one another, then to the yoke and the fuselage itself.  It's complicated.   

 

What I really wanted was to fill the opening with some chunk of material roughly looking like wrinkled fabric, poke a hole in it for the landing gear strut, and declare victory. Like I did with the pilot control stick.  But no - it won't be at all authentic.  Hence my dilemma.

 

Am currently leaning toward doing a super-duper job on the yoke and all its clap trap and leaving off the boot.....  

Edited June 23, 2018 by JayW

[NukerDan]

Wow, there's an awful lot going on in those drawings, isn't there? Good luck, whichever way you choose, I'm sure it'll look great!