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KH T-6/Harvard Kicked Up A Notch: Apr 14/20: Finished!


chuck540z3

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59 minutes ago, williamj said:

Well that was ingenious.:popcorn:

 

Thanks William, but not totally.  The reason that I didn't show both wheel wells modified is that one of my molds wasn't great, so I redid it .  After pulling the two epoxy parts out of the molds last night, I realized that I had re-done the same side twice!  Duh!   :BANGHEAD2:     I'll be doing the other side tonight, with hopefully the correct part this time.

 

Cheers,

Chuck

 

 

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On 1/21/2020 at 4:06 AM, chuck540z3 said:

January 21

 

Shortly after I started this build in November, LSP_Kevin pointed out that the main landing gear is too narrow and should be made wider.  He pointed out this article by Mike West on how to fix it:

 

Correcting the Kittyhawk Texan Landing Gear Position

 

This procedure looks really tricky and I’m not sure I could do it without making a big mess, so I tried to fix it another way.  When trying new things, sometimes I win and sometime I crash and burn, but it’s always fun trying.  I think I won this time, so let’s look at the problem a bit closer.

 

This is where the landing gear is located.  Note the gaps on either side between the gear legs and the gear bay opening.

 

 

iRHSPp.jpg

 

 

And this is what it should look like, with very little for a gap….

 

 

d22AR1.jpg

 

 

Here’s the problem.  That gear leg receptacle needs to be moved outwards and replace that double rib just to the left of it.  The problem is that the receptacle has a very specific angle from front to back and side to side, to keep the landing gear straight, so cutting it and moving it can have consequences if you don’t do it perfect.

 

 

3MJucs.jpg

 

 

If you could recreate the gear receptacle, you could place it wherever you wanted to.  About 8 years ago a modeling friend showed me a new Japanese polymer product that is fairly rigid plastic when at room temperature, but in boiling water (or other heat source) is becomes very pliable and is perfect for making molds.  I don’t know the name of it since all labeling is in Japanese, so here’s a pic.  I hunted around in Google and came up with another product that looks similar by a company called Polysis that they call “Haplafreely”.  I’m sure there are many other types now available.

 

 

2c4wB5.jpg

 

 

So I rolled up a couple blobs of the stuff and immersed it into a cup of boiling water and let it sit for a minute.

 

 

F4rFao.jpg

 

 

When warm and pliable, I then pushed the blobs over the parts I wanted to replicate, let them cool for a few minutes, then pulled them off.

 

 

ZEfArB.jpg

 

 

The mold detail within was excellent and I trimmed off the excess plastic.  Last time I used this product I was making small parts that had no real stress applied to them, so I used Tamiya Light Sensitive Putty.  I need something much stronger this time, so I used Gorilla Clear Epoxy that comes with two glue syringes for the epoxy and the hardener.  You apply an identical amount of each to a hard surface where you then mix them thoroughly together, which will stay in liquid form for up to 5 minutes.

 

oOBZqd.jpg

 

 

Using a small microbrush, I carefully filled each mold with the epoxy, being careful to not introduce air bubbles.  If air bubbles do form, you can poke them with a toothpick in a plunging motion, but you need to do it fast before the epoxy starts to harden.  Note the epoxy is raised a bit over the top (at the bottom of the part), to ensure the void is completely filled.

 

 

emhd8M.jpg

 

 

24 hours later, you can pull the epoxy out of the mold, which is now very hard and won’t stick to the polymer.  I then sanded the bottom flush and trimmed any flash.  Voila!  A new landing gear anchor point that is identical to the original.  The epoxy does not shrink and although very hard, still retains a slight bit of plasticity so that it won’t break under stress.

 

 

v5MboD.jpg

 

 

I then cut out the two ribs at the back and rather than completely remove the old anchor, I retained the back for added strength where the new part was glued in using CA glue, creating a solid mass.  The new anchor is lined up exactly like the old one as shown with the red line.  Note that I was able to retain the pins and angle detail at the front, which Parts F21 and F-22 are glued to, without a lot of sanding mess to clean up.

 

 

ZYRVhJ.jpg

 

 

Part F-22 and the gear leg dry fit into place.

 

 

DrIOXy.jpg

 

 

And the new landing gear alignment, which is just about perfect in all directions. 

 

 

3Ze3Hw.jpg

 

 

That’s about it guys.  A little experiment that went well for a change, which is super easy to do.

 

 

Cheers,

Chuck

Lovely work Chuck, but are you sure the landing gear was that far off? I know nothing about the aircraft but even in the picture you posted, I can see quite a gap on the port side. I don't know if this is the right variant, but again, on this picture, there's a pretty large gap between the leg and the bay, particularly once you allow for the thickness of the u/c door. The u/c door angles outwards slightly but not by much, and so the leg is pretty much the width of the wheel away from the side of the well.

T-6_0005.jpg

 

 

It seems to me that when you put the wheel on your leg, it will protrude past the ridges on the wing? That seems too far? Even on your picture, that seems too far?

 

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46 minutes ago, thammond65 said:

Lovely work Chuck, but are you sure the landing gear was that far off? I know nothing about the aircraft but even in the picture you posted, I can see quite a gap on the port side. I don't know if this is the right variant, but again, on this picture, there's a pretty large gap between the leg and the bay, particularly once you allow for the thickness of the u/c door. The u/c door angles outwards slightly but not by much, and so the leg is pretty much the width of the wheel away from the side of the well.

 

 

It seems to me that when you put the wheel on your leg, it will protrude past the ridges on the wing? That seems too far? Even on your picture, that seems too far?

 

 

You are correct, but where I have put the gear leg is much better than where it was before.  Here it is again, showing that once the tire is attached, it will likely protrude slightly over the wing rib on the outside (but barely), rather than just inside it like the pic you have provided above.  The gear doors, which I'm not going to be using, can still be attached and will angle over those same ribs like the real deal.  The gap between door and leg is narrower than it should be, but without doors it won't be noticeable.

 

3Ze3Hw.jpg

 

 

And here is why it is where it is.  The new part I created is pretty strong, but is much stronger when glued to the original part as reinforcement.  All of the weight of the model will be on these locations, so strength is very important.  To get the location as accurate as possible, I would need to cut this part out, which I don't want to do.

 

 

ZYRVhJ.jpg

 

 

In summary, without trying to be too defensive, there's not a lot about this model that is perfect to begin with, so if the landing gear is out a few inches when compared to the real deal, I'm OK with that.

 

Cheers,

Chuck

 

 

 

 

 

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On 1/21/2020 at 4:18 AM, Chek said:

Chuck referring back to your tail control surfaces, I'd suggest varnishing strips cut from hand rolled cigarette papers laid over the rivets. That would help disguise their rivetty nature and simulate the knots under a fabric strip slightly better. Slight unevenness where the varnish locally tensions the strips over the rivet heads as they dry will also help sell the illusion.

 

Strips of foil would work too.

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20 hours ago, TwoHands said:

 

Strips of foil would work too.

 

Thanks for the suggestion.  Last night I tried a number of things to add a tape-like cover to my Archer rivets to try and replicate the close-up pics of the orange Texan/Harvard below, including thin self adhesive foil.  While it did look a bit like the real deal, it didn't for scale.  This pic is taken from, say, 3 feet away, so at 1/32 it would be close to only 1 inch away.  At 6 feet away you can barely tell there is a tape like surface, but you can see a clear lumpy ridge.  With foil, cigarette paper and a number of other thin coverings on this model, you can easily see the cover from 1 foot away, which is the equivalent of 32 feet away, which is distracting rather than an enhancement.  While plain Archer rivets aren't accurate either, they still look better than the big ridges on the kit parts, just like the position of the landing gear being a bit off.

 

 

zSYvC1.jpg

 

9 hours ago, MikeMaben said:

Qh8SSr2.png

 

Thanks for that schematic drawing, which has some interesting tips like the color of the landing lights in the wing, which I'm about to paint before assembling the wings.

 

Cheers,

Chuck

 

Edited by chuck540z3
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1 hour ago, steel_tiger said:

Thin strips of clear decal film?

 

I thought of that too, which presents two other problems.  First, in order to get the film to stick, I will need to use Microsol, which will likely conform to the raised rivet detail and leave it totally exposed with just decal film on either side of it, which achieves nothing.  Second, and one that I'm not that proud to admit, is that I'm afraid some contest judge will look at my work in the future and think that I did a crappy job of applying the Archer decal rivets, because decal film is always an issue with this product.  And before someone chimes in and says, "You should build for yourself!", I freely admit that I don't always do that and when I enter a model at a contest, my goal is to win my category.  There, I said it.  I like to win.  :o   Raised rivets may not look as accurate as covered ones, but exposed decal film could be considered a deduction. 

 

Cheers,

Chuck

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January 30, 2020

 

A BIG update today!  Lots of corrections that were very challenging, but now that they are finally done, I can now say it was mostly fun.  First off, here’s a pic of both landing gear installed, since I only did one last time.

 

BEFORE:

 

iRHSPp.jpg

 

 

AFTER:

 

zXPG7i.jpg

 

 

With the inner wings now glued together, they show some fairly big gaps in the wheel wells.  If you use Eduard PE like I did, you will actually want those gaps as you will see.  There’s also no less than 8 holes for the fuel tank that will have to be filled, since I’m not installing one.

 

 

f9broO.jpg

 

 

There are also big seams in the wheel wells, which the Eduard PE kit will also cover.

 

 

o91mV9.jpg

 

 

I always buy every Eduard PE kit I can find for each of my builds, but I rarely use more than half of it, mostly because the PE is not necessarily better than the kit plastic and some assemblies are so fiddly, they aren’t worth the effort.  For this build, however, I’m going to be using 80% of it, including the super detailed and complicated landing flaps, which are usually hanging down when the aircraft is parked, so this detail is quite visible and should be worth the extra effort.  Here’s what you start with.  Unless you have dealt with PE a lot before, this assembly could wind up in the garbage fairly quickly.

 

 

xFTk9m.jpg

 

 

Tools of the trade when dealing with PE, and for the folds required for the long flaps, I have my handy 4” “Hold and Fold” from The Small Shop.  Using thin CA glue and having CA Debonder on hand, glue mess is kept at a minimum.

 

 

QuST78.jpg

 

 

Before assembly of the PE, you need to trim off the kit plastic detail with a knife and sandpaper.  I also filled the fuel tank holes with styrene rod instead of filler, assuming that the real deal has anchor points for the tank assembly.  Anybody know?  I can’t find a pic of the belly for a reference.

 

 

8YrAAQ.jpg

 

 

I assembled the central flap assemblies first, thinking that if I screwed up, they would be less visible.  They turned out looking just fine- and here they are compared to the kit flap at the top.  Everything below is only dry fit until final assembly and painting, to help avoid breakage or bending.

 

 

wH5F8n.jpg

 

 

With the central flap done, the outer wing flaps were much easier to do, once I got the hang of what exactly to do.  There are a few errors in the instructions, which I figured out with the first assembly.

 

 

RqaiLd.jpg

 

 

Dry fit in one wing, with the unmodified kit wing on the bottom for comparison.  Like night and day for detail and the PE parts fit perfectly.

 

 

FtA22m.jpg

 

 

Before gluing the central wing to the fuselage, the floor should be painted green since you can see part of it from above- something the instructions do not mention.

 

 

1VfpSN.jpg

 

 

To get the fuselage to fit into the inner wing, I had to sand both the sides and the anchor points on the bottom.  The fit is nice and tight, which is a lot better than a sloppy fit that requires filler.

 

 

yZDcEZ.jpg

 

 

Here’s where the Eduard PE kit really shines, hiding all the blemishes of the kit gear wells while adding some interesting detail.  I think the kit hydraulic lines are enough without adding more of them, partly because they will all be painted and partly because I don’t detail landing gear wells anymore.  If I must flip the model over to see this detail, which I never do, I don’t think it’s worth it.  Note that the PE actually fits in the gap the kit parts left behind.  I also added a vent hole with screen on the port side wing as per references.

 

 

TtA3Qb.jpg

 

 

Another angle, which begins to show a few of the new curved panel lines I added to the top and bottom that are missing.

 

 

VOxXdp.jpg

 

 

The are several panels on the top of the gear wells that interlock in a predictable pattern according to references, but the kit parts don’t have them and further, the gear wells should extend further outwards on either side.   As a compromise using many pics from various angles, this is what I did to try and replicate same.  The curved panel lines were very hard to do, partly because they are curved, but also because they are on curved surfaces, so scribing them cleanly in the plastic was a real challenge.   Not perfect, but a lot better than before and with yellow paint filling everything, flaws within these panel lines will likely disappear.  Note that the wing to fuselage seam that I filled is where most black walkways angle at the front, which is due to a panel that covers the fuselage to wing seam that should not be walked on.  As with the rest of the build, all panel lines and rivets were redone.

 

 

vKJv1k.jpg

 

 

zMNtc4.jpg

 

 

The other side…..

 

 

8oyff2.jpg

 

 

Finally, I added several large fasteners with my Mega-Tool according to references. 

 

 

za918t.jpg

 

 

I’m guessing the rest of this build will be relatively easy, since I think all the real tricky parts of this build are over?  Time will tell- and I’m already going to be changing the landing lights significantly!  Thanks for your continued interest in this Texan/Harvard.

 

 

Cheers,

Chuck

Edited by chuck540z3
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