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1/18 Scale Blue Box F4U-1A Corsair Modification


JayW

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Stupendous work, Jaybo.

 

'Cannot tell how hard I worked on these details'

Anyone that scratch builds can tell how hard you worked on those details.

 

'The foot troughs are going to be a giant challenge, as they cannot go in until after the cockpit walls and bottom are joined.'

Odd.  Why is that?

 

Sincerely,

Mark

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15 hours ago, JayW said:

Again, the magnification shows the flaws.  It looks alot more convincing from a few feet away.   

Well.... looks pretty damned convincing to me.  :) Exquisite workmanship.

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5 hours ago, dodgem37 said:

'The foot troughs are going to be a giant challenge, as they cannot go in until after the cockpit walls and bottom are joined.'

Odd.  Why is that?

OK Mark.  Mostly, it is because the rudder pedals.  If they were attached to the side fuselage halves like the foot troughs, I could do it.  But they are not.  The rudder control mechanisms come up from bilge-mounted fittings on the lower longerons, alongside of the troughs, on the lower/fuselage wing part.  And the pedals themselves cantilever inboard from the mechanisms directly over the troughs of course.  If I were to install the troughs to the fuselage sidewalls prior to mating the LH and RH sides together, and then to the bottom fuselage, the troughs would clash directly with the rudder pedals as I lowered it onto the bottom fuselage part.  I have already ruled out sequencing it so one side is attached to the lower fuselage, and then the other side.  That has major problems of its own.   Really - there is no good way to attach those troughs.  They are supported in three places.  The aft ends by the large brackets aforementioned (one LH and one RH).  These brackets must be attached to the fuselage sidewalls as I have shown in the picture in the last post.  The forward ends attach to clips on what I call the "zigzag" bulkhead - the forward most bulkhead in front of the rudder pedals.  This bulkhead I have glued to the LH fuselage sidewall.  And in the middle the troughs are supported by struts that attach to the bottom segment of the Sta 138 bulkhead.  That bulkhead is part of the bottom fuselage/wing part.   Tamiya looks to have created a capsule of sorts for the entire cockpit, and then it gets inserted into the fuselage.  I do not have that option.   It is one of the many details in the cockpit which I do not have good plans for.  

 

ad91aOAh.jpg

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23 minutes ago, Oldbaldguy said:

Hey, is yer “hydraulic hand pump” a pump for hydraulics or is it a wobble pump for the fuel system?  Seeing as how it looks like it is attached to the fuel selector valve and all.

Well it shares a bracket with the fuel selector valve, but is not attached to it.  Here is some info on that hand pump:

 

Hqs4M6Sh.jpg

 

f3zrl4Eh.jpg

 

Definitely hydraulic system component.  I have not yet put in those two hydraulic lines you see in figure 500 above.  Thanks for your interest in this build!  

Edited by JayW
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On 2/22/2021 at 4:00 AM, dodgem37 said:

Thank you, Jay.  Did you get your references from AirCorps?

 

Oh yes Mark.  Just about everything.  Cannot say enough about that site.  There are occasional gaps however - absent drawings, or drawing that are unreadable.  Then it's web searches, reviewing of publications, or just plain WAG's.

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Oh man Jay, this is like looking at a full size restoration! Those CO2 bottles are exquisite :) Really love the planning that goes into your work; all too often I get distracted with certain details without seeing others for what they are (and their importance!!). That you can decipher all the drawings you have (especially when they quite often contradict each other) is a rare type of talent!

 

I have leaned heavily on aircorps library too, but as you've said, sometimes the drawings are frustratingly too light or dark to make sense of (or there are multiple versions and it's hard to find what's changed in each!)

 

Keep it up Jay, this is absolutely incredible.

 

Craig

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On 2/23/2021 at 2:02 PM, brahman104 said:

Oh man Jay, this is like looking at a full size restoration! Those CO2 bottles are exquisite :) Really love the planning that goes into your work; all too often I get distracted with certain details without seeing others for what they are (and their importance!!). That you can decipher all the drawings you have (especially when they quite often contradict each other) is a rare type of talent!

 

Hi Craig - always enjoy hearing from you.  I am glad you think so much of this build so far.  Two things to say:

 

1.  As for navigating the Aircorps Library, that is so up my alley you wouldn't believe.  My entire professional career at the big airplane company as well as its helicopter division involved working with engineering drawings and navigating the drawing trees for a host of product lines.  Just like anyone in my position, I learned all the in's and out's of studying configurations as defined on engineering drawings in order to create new design or modified design, or to analyze them for one thing or another.  One had to be well versed in determining what aircraft had what part or assembly or installation.  So chasing part numbers and "NHA's" (next higher assemblies), or "used-on's" (another term for NHA), parts list information, effectivities (blocks of airplanes in which an installation is used on), etc, was part of the job.  The 747 is a shining example.  It's drawing system is very similar to what we see in Aircorps Library although much much bigger.  With drawings that have embodied in them all the history of the product line from the original -100 to the -400 (past that, the drawings went digital).  Very complex.  I think the toughest drawing tree to navigate was the CH-47 - something I was presented with right out of college way back when.

 

2.  Push is getting to shove with the Corsair cockpit.  I could see at the outset that ultimately the cockpit integration was going to be all but impossible at some point in the build.  If I were to do hydraulic lines, control cables, electrical wiring, fuel hoses, etc (which I am doing to the best of my ability), terminating these runs to their end points was going to involve as often as not partial positioning of a component and waiting for fuselage half join and/or joining to the lower fuselage/wing to finish it, or just waiting until all that joining was complete to even begin to install a hydraulic line or a hose or the like.  This also applies to some of the structure (like the foot troughs for example, but there are more examples).   Once all that joining is complete, I am presented with a deep dark hole with access only from the top (with the sliding canopy, windshield, coaming and IP not installed), or the aft end through the Sta 186 bulkhead (with the armor plate and seat not installed).  Both means of access are limited, with long and narrow reach required.  I have not had this challenge, not nearly to this degree at least, on my other builds.  So far what I have posted has been stuff that has relatively easy access to get done - "low hanging fruit" so to speak.  There is more to go especially on the RH side of the cockpit.  But in the not too distant future, I will run out of the low hanging fruit and the real challenges begin.  Some things I am going to have to give up on, I'm certain.  Some things will be ultimately successful but perhaps not as pretty as I'd hoped, or result in breakages that must be repaired (repairs almost always are not as good as what was there prior to injury).

 

Anyway, like so many of the builds we post, they can be high adventure at times with alot of work at stake.  We love it don't we?  

Edited by JayW
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Sounds like you had an amazing career Jay! Amusing that you said the CH47 was the hardest to navigate! Man I miss working on that aircraft....... European stuff just doesn't do it for me! I recently scrolled through the entire B-17 list on Aircorps library, but I still couldn't work out their logic in the drawing numbers, especially when one drawing will be a washer, and the next in the sequence will be a general arrangement, then the next a wing rib! Maybe I'm just challenged but I couldn't figure out the system..... hence having to scroll through the whole library!!! hahaha!, it was great fun though, and I stumbled across some really cool early model stuff in the process.

 

Totally get what you mean regarding access, I've always loved the challenge of working out the right steps and processes, but definitely no-where near the level you're taking on here! 

 

Can't wait to see your next move :)

 

Craig

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In my last update, I said I needed to install the bilge-mounted fuel pump in order to better visualize and plan for the hydraulic lines and fuel hoses coming off the hand pump and fuel selector valve on the LH sidewall of the cockpit.  And that is true.  But installing the fuel pump would block access to installation of the rudder pedals.  So I had to fabricate and install the rudder pedals (at least the LH side one) first.  Either that or don't yet install the fuel pump.  I elected for the former option, probably a mistake - the rudder pedal is just dying to be broken off now that it's there.  I get ahead of myself....

 

Before the rudder pedals and the fuel pump installations, I got more or less fed up with all the cables (fishing line) sprouting out all over the place, hindering my work.  So I decided to organize them better by fabricating and installing what I will call the "master" cable pulley bracket.  In real life this large complex bracket is located on the lower LH sidewall forward of the rudder pedals (so will be largely or maybe totally unseen).  Importantly though, it gathers and routes cable runs for aileron trim tab (two), bomb release (two), bomb arm (two), wing hinge pin lock indication (two), and landing gear position indication (two).  All these cables emanate either from the LH console or the LH aux instrument panel.  And like a fool, I have represented nearly all these control cables - and they are in bad need of being organized.  

 

I make pulley wheels using thin plastic and the Waldron punch, in this case 0.120 inch diameter and 0.081 inch diameter.  Here are five (five!!) pulley wheels stacked on top of one another (you don't see that very often!):

 

    LHkSReil.jpg

 

Another stack of pulley wheels (three) ads to that one above.  And the bracket itself, installed:

 

1hDsdJNl.jpg

 

Can you see the three pulley wheels stacked?  The five-stack is totally invisible in between the bracket halves.  So no longer do I have fishing line getting in the way (yay!).  But to my disappointment but not particularly to my surprise, the cable run has a kink in it where it passes through the foot trough bracket (see above).   Crap - I wanted a good clean untangled run....

 

Chalk this up to the thick gage of the fuselage sides, and some less-than-excellent layout on my part.  A full digital layout would probably have shown this before I made stuff.  It is what it is though, and it's my hope that the error gets lost in the shadows and the sea of detail that is a Corsair cockpit.  Panning back with the fuselage halves in place:

 

RPAZauDl.jpg

 

Add the foot trough, and that "ugly cable run" won't be that visible, methinks.

 

 That done and it was on to the rudder pedals.  I am not sure how visible (or invisible) the rudder pedals will be.  On my other 1/18 efforts, where I worked hard on rudder pedals, they are just about invisible.  I have some reason to believe they are a little more visible on the Corsair (??).  Well here we go.  Here is the assembly drawing of the pedal:

 

  6rW3CcLl.jpg

 

Note the typical reach adjustment sector (looks like an ice axe).  And the pedal angle pull handle adjustor.

 

And midway along with fabrication:

 

d6p5jobl.jpg

 

See that spring on the LH pedal (and not on the RH pedal)?  What alot of painstaking work with 0.008 music wire wrapped around a 0.032 drill bit!  Not to mention the microscopic lugs needed to attach it.  All for a detail that absolutely CANNOT be seen once installed into the cockpit.  I learned that prior to making the RH pedal, so you do not see it there.  This will become a recurring theme - increasingly skipping painful details because they cannot be seen.  The unpainted thing in the middle is one of the hydraulic brake cylinders (another detail that is practically invisible).  So I skipped some of its finer detail like the hydraulic line connection.  Otherwise it's made of simple plastic shapes like usual.  You also see the beginnings of the pedal details with side plates, a pivoting brass tube, and a curved web.  I wish I knew how to make the grooved surfaces for the pilot's boot....

 

And installed:

 

 BZAoFfnl.jpg

 

You can see the mounting fittings glued to the lower longerons (done months ago).  You also see the fuel pump which I'll get to in a minute.  And, you see one of the rudder cables flailing around in the air.  This model WILL have rudder pedal cables come hell or high water.  So what's wrong with this picture?  Well the rudder pedal sticks up like an antenna!  And I still have to do dozens (maybe hundreds) of hours of work on the inner wing (like the LG bays).  How am I going to prevent the pedal from being broken off (smacks forehead)?  :(  Well I guess I will have to come up with some crude fairly robust cage to fix around it - I did something like that for the Thunderbolt's flap mechanisms a couple years ago.  Wish I had thought of that before I installed them - but in my defense sequencing the installation of the cockpit parts going forward is becoming more and more complicated.  

 

And once the rudder pedal mechanism was installed, I could get to the big fuel pump in the bottom of the cockpit:

 

      cUo8Tq5l.jpg

 

 

I made this out of something like a hundred little plastic and metal pieces - another micro-surgery project:

 

2a0UBPhl.jpg

 

This variety has a valve piggy-backed onto the pump housing that allows the externally mounted 160 gallon fuel tank to be drained (or filled?) without removing it from the airplane.  The "bird cage" Corsairs and earlier -1A's didn't get this valve because they didn't have that big drop tank.  Mine does though.  It has that red turn handle and the two brass rods sticking out to accept fuel hoses later.  It was designed to barely fit underneath the foot trough.  Uh oh.... 

 

Here, sure enough, is the clash:

 

YLvoIjEl.jpg

 

The foot trough of course is temp installed just to study the fit.  I think this occurred because the foot trough mounting bracket is a tad low.  So what to do....  First I cut off a couple hundredths from the red handle and the elbow fitting on top of the valve.  Then I scraped a couple hundredths off the bottom of the foot trough.  Later, I will shim the curved mounting interface between the trough and the bracket about 0.02 inch.  That should do the trick.

 

Do you get the impression this is a busy place?  You would be absolutely correct.  And I don't even have the intrusive fuel hoses for the fuel pump in place yet.  You may also sense a tinge of frustration in my descriptions?  Well I am trying to remind myself that model making is supposed to be fun.  But I must say, these details are HARD!  Labor intensive.  And I'm beginning to experience the downsides of my sequencing plan, with unanticipated inaccessible clearances to complete system runs, etc.  Clashes are starting to show up too.  So I have a bit of a mine field here, with so very much already invested in the cockpit build.  Trying to attach a rudder cable after the fuselage join has occurred - OMG.  Or attach the fuel hose to the top of the fuel pump valve.  I don't even want to think about it right now.      

 

Next post I will add to the business with the engine control quadrant.  Then it's the flap control unit to close out the LH side!!!  Milestone.  Stay tuned!  

  

Edited by JayW
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