Jump to content

1/18 Scale P-38 Lightning


JayW

Recommended Posts

All right - aft canopy. 

 

Here is the toy part - it isn't too bad, but its length isn't quite right and it looks rather toyish.

 

002_zpshwyjgw8y.jpg

 

It's section shape is to be kept, so I used it as a guide to make the sta 154 canopy frame (cut from .02 plastic sheet stock):

 

001_zpszeglbiak.jpg

 

Adding some rod stock for window lands it looks like this (no big deal):

 

004_zpsfv9spl7c.jpg

 

The two aft window panes are separated by a centerline spine.  I think it wants to be pretty stiff, so I made its middle portion from .015 inch aluminum sheet.  Here I scribed the shape (sorry alot of messy scribe lnes there) with the curved shape cut out already:

 

005_zpsxmso7teh.jpg

 

So aluminum tends to curl and mal-form when cut with snips or scissors, so I did the final cut on the end mill:

 

006_zpsu1dt3xew.jpg

 

After I got that part cleaned up, I bonded some .06 plastic stock to either side to provide the window lands.  So my frame components are here:

 

007_zpsp4metafd.jpg

 

OK, pretty boring so far, but it's critical work.

 

After some careful measuring and dry fitting, I installed these parts to the fuselage:

 

009_zpsxnjme7va.jpg

 

008_zpsmpp6bd0u.jpg

 

You will see the spot defroster hose hanging nicely from the frame - Oh Yeah.  The aft end of the spine was shear clipped onto the closeout frame at the end of the radio compartment.

 

So now the easy part is done. 

 

Here is a test part for the LH window pane:

 

010_zpsntggd61g.jpg

 

It does not want to double wrap, but I have some reason to think it's going to be OK.  Wish me luck.  Next post should have the window glass in there plus its framing strips.

Link to comment
Share on other sites

Well - on the aft canopy, I guess I am going to declare victory.  The double curvature indeed was a bit of a problem.  It manifested itself in the center of each panel being a little flatter than it should be, so it is slightly mis-shapen.  But you have to look for it.  Let's commence with some pictures.

 

I developed flat patterns, but you know that because I showed the test part last post.  Here are the clear parts:

 

001_zpstrl8wmaj.jpg

 

Here the clear panes have been bonded into place.  If you look for it, you can see that the curvature is a little muted in the middle of the panel:

 

002_zpskdgvmbsx.jpg

 

Now for the framing - here is a typical strip:

 

003_zpszct4h9ln.jpg

 

Computer generated flat patterns are invaluable here.

 

So (drum roll please) here is the finished aft canopy:

 

004_zpsam2jgm1l.jpg

 

005_zps92prfh4l.jpg

 

006_zpssqb9rmjz.jpg

 

Tell me what you think.

 

I think it is time to finish up a few items on the fuselage, button it up, and get it painted.  I am some kind of anxious to see the nose art and score board.

 

After that I will complete the side windows and hatch.  I am taking suggestions on how  to fabricate the exterior rear view mirror (it is supposed to be clear).

Link to comment
Share on other sites

  • 2 weeks later...

Gonna try something a little different.  I'll show pictures and not say what the part is until last (hint - it has something to do with the hatch)

 

001_zpsyfieylfx.jpg

 

Lathe work?  Clear acrylic?

 

002_zpsojia2jgy.jpg

 

End mill work?

 

003_zpsd13wxjuz.jpg

 

What a mess - does this guy have any idea what he is doing?

 

005_zpsgnrxcoum.jpg

 

OK, that duck billed shape should be a good clue.

 

006_zps9ighasvl.jpg

 

And there it is - the rear view mirror, shaped pretty much to scale.

 

More next post (coming immediately).

Link to comment
Share on other sites

Recall this is what I am trying to improve on:

 

004_zps115dd551.jpg

 

Here is the completed hatch.  As I said before, it is the only thing I salvaged from the original canopy:

 

007_zpsxz0foumw.jpg

 

The curved interface with the side windows was ground down to be flat, the molded shapes on top which were supposed to be rear view mirror and hinge were ground away and polished, and replaced with the new machined acrylic rear view mirror, and a better hinge made from some plastic sheet and rod.  A little sad - but the hatch will not be able to be rotated up.  Here is another view:

 

008_zpsl7pgskkr.jpg

 

The side windows were much easier than anything else on the canopy - they are merely .01 inch clear plastic sheet with strips glued on:

 

009_zpskmwwyll6.jpg

 

These windows can slide into grooves on the canopy frames. 

 

So this is another nice milestone - complete canopy, with paint.  Here are some shots:

 

010_zpsdh9ybcxc.jpg

 

011_zps3tbw0esw.jpg

 

014_zpsmcr5plgt.jpg

 

And with the nose:

 

013_zpss37iqrsu.jpg

 

012_zpsu4nvyuzz.jpg

 

This effort is far from perfect.  If I had it to do over again I would do a few things differently, like figure out how to get the aft glass more "blown", and redesign it such that the hatch could be opened.  But it's far better than what the toy provided.

 

I will now make little stub side windows, at least for one side, so it can depict an open position.

 

Then it's the four fuel filler caps on top of the center wing, and the ID lights on the bottom of the fuselage.  These will be all  new.  Then and only then can I button up the fuselage and commence with panels lines, etc. 

 

Please stay tuned!

Link to comment
Share on other sites

wow, fantastic!

 

I will also need to remake the windshield on my 1/18 Dauntless. Can you confirm your technique for making the clear parts is outlined somewhere earlier in your build thread? I don't want to trawl through pages of stuff again (even though I have read the whole thing).  Many thanks

Link to comment
Share on other sites

Hi richdlc - I wonder if you are doing a Merit Dauntless.  I just went over a long thread by Phillip1 on his fantastic model, where he used the kit parts which look good to me.  Why not use them?  Anyway, I took a hard look at the windshield, as I am not very familiar with the Dauntless.

 

So I do not possess a vacuform.  I believe that is the key - that and the ability to make a good mold.  I have never tried since I don't have the vacuform.  What I have done however is made "glass" that is single curvature or nearly so.  Even that has limitations (at least for me).  What I found with the P-38 (or, was reminded of) is that clear plastic sheet is more brittle and less inclined to take on a shape other than flat than its equivalent thickness white styrene, for reasons unknown to  me.  And if you ask it to do more than it wants, it will reward you with a cataract effect where the material that is forced to flow from bending or shearing begins to lose its transparent characteristic, also for reasons unknown to me.  I actually tried using my oven to soften the plastic, just as an experiment to see if I could avoid some of these things, and had poor results.  First - temperature is critical as well as time in the oven.  Temps more than 140 deg or so resulted in mal-forming that was not controllable (I think that is what the vacuform is all about!).  And second, the very act of elevating the temperature enough to soften the clear plastic seemed to start to turn it opaque.  I know there are folks out there who know how to do this; I am not one of them.

 

So what I can do is create accurate flat patterns for single curvature parts that do not have excessive curvature (example - P-51D side glass).  That requires either skills as a draftsman where you can flatten out a curved 3D surface, or a computer drafting/designing program that can do it for you (that's what I do).  Once that is done you simply warp the plastic sheet around something round (and smooth) to give it some curvature fairly near its final shape.  From there you have to make sure you have a frame that accepts this part - something that has a backing that you can force it into shape.  That can be difficult to do without looking messy.  Such backing has to be covered by exterior strips (which most aircraft glass enclosures have anyway).

 

The Dauntless windshield looks like trouble to me.  The basic windshield is single curvature, since a side view profile is a straight line.  You need that if you are not vacuforming.  But the radius of the curve is tight.   If I were doing it, I would find that the material doesn't want to be that curved, and would start to go opaque.  The thinner the gage, the more curvature it will accept.  I am sure 0.010 inch thick is too thick for that curvature (that is what I used for the P-38).  Perhaps .007 or .005 if it exists would do it.

 

The top of the windshield however is blown - it has a spherical shape that cannot be done with simple techniques.  You either use that portion of the kit windshield, or you use a vacuform and a mold.   That is the reason you see the kit hatch on the P-38.

 

Good luck on the Dauntless - let me know if you have it posted; I would like to look in!

Link to comment
Share on other sites

Jay,

 

I am consistently amazed at how you are turning this toy into a work of art. Although I stepped away from 1/18 (except for my Tiger and Panther), now I wish I had kept a couple to see what I could make out of them. Just shows that with a little patience (and a lot of skill) one can turn a mutt of a kit into a purebred show winner.

Link to comment
Share on other sites

Hi richdlc - I wonder if you are doing a Merit Dauntless.  I just went over a long thread by Phillip1 on his fantastic model, where he used the kit parts which look good to me.  Why not use them?  Anyway, I took a hard look at the windshield, as I am not very familiar with the Dauntless.

 

So I do not possess a vacuform.  I believe that is the key - that and the ability to make a good mold.  I have never tried since I don't have the vacuform.  What I have done however is made "glass" that is single curvature or nearly so.  Even that has limitations (at least for me).  What I found with the P-38 (or, was reminded of) is that clear plastic sheet is more brittle and less inclined to take on a shape other than flat than its equivalent thickness white styrene, for reasons unknown to  me.  And if you ask it to do more than it wants, it will reward you with a cataract effect where the material that is forced to flow from bending or shearing begins to lose its transparent characteristic, also for reasons unknown to me.  I actually tried using my oven to soften the plastic, just as an experiment to see if I could avoid some of these things, and had poor results.  First - temperature is critical as well as time in the oven.  Temps more than 140 deg or so resulted in mal-forming that was not controllable (I think that is what the vacuform is all about!).  And second, the very act of elevating the temperature enough to soften the clear plastic seemed to start to turn it opaque.  I know there are folks out there who know how to do this; I am not one of them.

 

So what I can do is create accurate flat patterns for single curvature parts that do not have excessive curvature (example - P-51D side glass).  That requires either skills as a draftsman where you can flatten out a curved 3D surface, or a computer drafting/designing program that can do it for you (that's what I do).  Once that is done you simply warp the plastic sheet around something round (and smooth) to give it some curvature fairly near its final shape.  From there you have to make sure you have a frame that accepts this part - something that has a backing that you can force it into shape.  That can be difficult to do without looking messy.  Such backing has to be covered by exterior strips (which most aircraft glass enclosures have anyway).

 

The Dauntless windshield looks like trouble to me.  The basic windshield is single curvature, since a side view profile is a straight line.  You need that if you are not vacuforming.  But the radius of the curve is tight.   If I were doing it, I would find that the material doesn't want to be that curved, and would start to go opaque.  The thinner the gage, the more curvature it will accept.  I am sure 0.010 inch thick is too thick for that curvature (that is what I used for the P-38).  Perhaps .007 or .005 if it exists would do it.

 

The top of the windshield however is blown - it has a spherical shape that cannot be done with simple techniques.  You either use that portion of the kit windshield, or you use a vacuform and a mold.   That is the reason you see the kit hatch on the P-38.

 

Good luck on the Dauntless - let me know if you have it posted; I would like to look in!

 

thanks for the reply...  I will have to look into this more carefully.  I can't use the kit windshield (at least not all of it) as I am making a dash 5 model. The kit is a dash 3/4 which has the old style telescopic sight running through the windshield. The dash 5 model has solid windshield glass.

 

And yes, I have the build on this forum - updated it yesterday in fact:

 

http://forum.largescaleplanes.com/index.php?showtopic=53741

Link to comment
Share on other sites

  • 2 weeks later...

Hello LSP folks - I must apologize for the snail's pace I have been progressing at.  Thanks for your patience, those of you who are still following.  The panel line work on the center fuselage has been daunting work - it seems like the trenches go on for miles.  I am now at a place, though, where I can button up the fuselage halves and concentrate on finishing the center fuselage.  At that point I will move outward and attack the panel lines on the center wing panels.  They are started already but I did a terrible job filling them in and I need to fill some more.  So pay no attention to them. 

 

First, two items had to be remedied before bonding together the fuselage upper and lower halves - the fuel filler caps and the ID lights both of which are represented very badly on the 21CT toy.  I had been brooding how to re-do the filler caps and then had a Eureka moment and decided to turn them on a lathe and then end mill grooves in them.  Then I simply added strip styrene for the handles.  Here: 

 

002_zpsye9wecub.jpg

 

Why brass?  No good reason; they should have been acrylic; I had the right stock size.  This model is getting heavy especially with the balast in the nose, and the brass plugs that simulate the fuel filler caps have weight.

 

Anyway - here is how they look on the wing:

 

003_zpsx3mfiohs.jpg

 

There are four in the center wing, and two more on the outer wings (one each side).  The outer wing work is eons away, it seems.

 

Here is a shot of the new ID lights (they were easy - made out of a thick piece of plastic with drilled holes and tube installed in the holes):

 

005_zpsmruxqnjg.jpg

 

Like a dummy, I neglected to take a shot of the "before", but suffice it to say it looked unconvincing.  Once I color the insides and drop epoxy into the three holes, it will look convincing to anyone who bothers to turn the big Lightning upside down (won't be easy to do).

 

Here is the ugly beast that is the lower center fuselage prior to primer - lines have been filled and the other suff I mentioned is done; only rescribing remains (after primer, and then repairs and more primer:

 

004_zps6bsvj7d9.jpg

 

Here is the primed part - soon as it dries fully it gets glued and screwed to the top half:

 

006_zpsuiarjiyp.jpg

 

Then it's going to get fun.  Time to make decals....stay tuned.

Link to comment
Share on other sites

Awesome patience & professionalism - there is plenty of really good problem solving going into this, well done! Really enjoying seeing it come together, one day I'd love to tackle one of these 21CT kits. If I ever have the space ...

 

Cheers

Jim

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...