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1:72 Grumman/General Dynamics F-111B "Beta Tomcat"


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A little work done on the cockpit - since everything was grey on grey (Dark Gull Gray pit, grey-green cushions, grey harness) I thought I would go a little heavier on the wash than I usually do. Probably overdid it slightly, but this may all be hidden under the canopy anyway. I haven't decided if I want to risk cutting open the Hasegawa canopy, as I only have one, and I kinda like the F-111 with the windows closed. We'll see.

 

IMG_1282

 

I stole the photoetch harnesses from an F-14 fret, so they're most likely not correct. I mounted the ejection seats so that the headrest seemed to be at the same height as seen in photos. Should be OK.

 

I've also started work on the intake channels, painting everything white and getting ready to assemble the main fuselage. The front and rear bulkheads in the main gear bay have a nasty seam right down the middle, so this was filled and sanded prior to building the bay and mounting it in the bottom fuselage. Oddly, there are no positive guides for positioning the bay in the correct spot. I resorted to taping the entire fuselage together, save the top, so I could get the bay in the right spot. Even then, it's not a great fit where it meets the forward fuselage sides, but that will be hidden under the intakes.

 

I built the Hasegawa FB-111A ages ago and I don't recall this issue. But then, I don't recall a lot of stuff from days gone by! I was going to use this build as the basis of my F-111B, but went and bought a new kit instead. The FB lives to fight another day.

 

Cheers,

Bill

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Tommy Thomason, aka @Tailspin Turtle, has a great blog called "Tailhook Topics." To learn more about the F-111B, go to this page:

 

http://tailspintopics.blogspot.com/2015/03/the-complete-f-111b.html

 

Follow all the various links and you can learn a lot about the history of this aircraft. If you go to this link...

 

http://tailspintopics.blogspot.com/2009/10/grumman-f-111b.html

 

...and scroll down a bit, you'll find a superb drawing that shows the differences between the different intakes used on the F-111B prototypes. The intake ramp (splitter plate as I call them for some reason) on 151972 had an angled edge on the bottom, and was straight when viewed head-on. This is typical of the first F-111A intake ramps. There were no "blow-in" doors on the intake cowl, instead the outer surface of the cowling translated forward as seen here:

 

IN011a

 

My intention is to model the translating cowl in its forward position. 

 

The kit has two sets of intake parts available, one for what's called the Triple Plow I intake, and the other for the Triple Plow II. I'll be using the parts for the Triple Plow I since it most closely resembles what was on 151972. However, the ramp on the kit part does not have an angled bottom, and it has a kink when viewed head-on. Here's a great shot that shows the "kink" in the ramp up near the shock cone on the Triple Plow I intake (a lot of kits leave out this important kink, but Hasegawa has it correct):

 

IN007a

 

But I don't want that - my ramps have to be straight and angled on the bottom. I decided to use the basic kit part, but I'll remove the ramp and substitute one made from sheet styrene.

 

IMG_1287

 

When it's in place, it will look something like this:

 

IMG_1288

 

It's not perfect, but I think it will work. Once everything is all assembled it should look the part. Removing the kinked ramp from the kit part looks like it's easier said than done!   :) 

 

The picture that I used at the beginning of this thread shows the straight, angled bottom intake ramp nicely. Also note that the translating cowl is forward, as it typically was when the aircraft was on the ground. 

 

F-111B 151972 at Hughes

 

Cheers,

Bill

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Those are great photos Bill.

 

I had just done the same with my build, the way the splitter plate is modelled on HB models (and others by the looks of it) are wrong for the Triple Plow I intakes. As you mention there is the kink up the top on the forward section of the plate, plus the plate is not even with the intake at the bottom, it sits away for the intake and closer to the fuselage. It's actually parallel to the fuselage and the part of the intake next to it is not vertical but slightly off vertical so you have the gap at the base. The shape of the plate even uo remove the "kink" is not 100% flat, unfortunately don't show the subtlety in it's shape.

 

You're doing a great job on her!!

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Hi mates,

 

Nothing major to report on my Beta Tomcat build, just a bunch of little things. First, I managed to remove one of the moulded-on "kinked" ramps - I was a bit concerned here because I needed to ensure that the surface where the new ramp will mount is flat. I ended up using sanding sticks, of course, but with a little jig to help hold the part steady. That, and remembering that the sanding sticks are not flat themselves, usually being a bit convex on one side and concave on the other. Anyone else ever notice that? To get a flat surface, you need to flip them over occasionally as you work. The result:

 

IMG_1289

 

The new ramp fits nicely, and won't interfere with the translating cowl. The ramp is also at the right angle relative to the fuselage. Now to duplicate that on the other one...

 

Next up I wanted to work on the knife edge boat tail which adorned the early prototypes including 151972. Here I'll be using the old Revell kit part, which is quite good considering its age. It turns out that it is both the right height and nearly the right length for use with the Hasegawa fuselage (it's important for the top trailing edge of the boat tail to meet the bottom trailing edge of the rudder, without any step between the two). In order for the top surface of the Revell boat tail to be level with the top of the Hasegawa fuselage (so that the tail fin will fit nicely) it's necessary to add a small shim from card stock (this also makes it the right length):

 

IMG_1290

 

The Revell part has the rear portion of the arresting hook fairing moulded on its bottom - unfortunately, it's the later version of the hook design, with the fairing extended all the way back, so it had to be removed. I noticed in one photo of what I think is the early hook design, the bottom edge of the knife edge had a tiny protuberance or lip - I have no idea what this is or what it's for. You can see it here just below the fuel dump:

 

fuel dump

 

As I was removing the arresting hook fairing from the bottom of the boat tail, I tried to leave just enough so that this lip would remain.

 

IMG_1291

 

I have no clue if the lip should be there or not. It's possible that the photo above is of the later hook design, but with the fairing removed for some reason. I'll try to find out if the lip should remain - it will be easy to remove if necessary. In this photo of the early arresting hook design, the lip looks like it's there, but it's really hard to tell.

 

Early Tailhook

 

Speaking of arresting hook fairings, the resin part in the Pete's Hangar conversion kit is closer to the later design, but not particularly good at that, especially with respect to the hook itself:

 

IMG_1296

 

I'll be modifying the resin hook fairing, or scratch-building a new one. We'll see. Before we mount the Navy style arresting hook and tail bumper, we have to remove what is moulded on the bottom of the Hasegawa fuselage. A bit of work with a Dremel tool, and some 400 grit paper and it's gone - poof! The Hasegawa F-111G fuselage on the left, and my soon-to-be F-111B fuselage on the right:

 

IMG_1292

 

The knife edge boat tail has been mounted, and some putty applied to smooth it into the fuselage. Next up are the "speed bumps." It's just about time to connect the forward and aft fuselage assemblies, too. Then she'll start to look like an F-111.   :)

 

Cheers,

Bill

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1 hour ago, trickyrich said:

wow I love following your builds!! :popcorn:

 

Thanks - I have a question for you. Is the F-111 similar to the F-14 when on the ground engines off - one nozzle open and one closed? If I recall, you used to work on these babies. 

 

Cheers,

Bill

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I wish i had worked on F-14s!!! 

 

The F-111 does the same as the F-14 or the F-14 does the same as the F-111, one open (engine that stopped first) and one closed (last engine to stop). Again this is for the same reason, lose of hydraulics means the nozzle will stay in the last position when pressure drops off.

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On 5/2/2017 at 20:27, trickyrich said:

I wish i had worked on F-14s!!! 

 

The F-111 does the same as the F-14 or the F-14 does the same as the F-111, one open (engine that stopped first) and one closed (last engine to stop). Again this is for the same reason, lose of hydraulics means the nozzle will stay in the last position when pressure drops off.

 

Thanks - when I said "babies" I meant F-111s, I should have explained myself better. This page has a great description of why the F-14 does what it does when on the ground:

 

http://www.anft.net/f-14/f14-detail-engine.htm

 

You've probably seen that before. Is it a similar system on the F-111?

 

Here are a couple of new photos showing the aft end of the F-111B model. The knife edge boat tail is on, and I've just added the "speed bumps." The speed bumps aren't a perfect fit, but they're not bad - especially considering that the Revell kit, where the speed bumps came from, is from 1966. A little putty will blend things in nicely.

 

IMG_1297

 

IMG_1298

 

I'm pleased so far with how things are going. Of course, I haven't chopped off the nose yet!   :)

 

The radar warning receivers on the horizontal tailplanes need to come off, as these weren't on the F-111B. I can't wait to get some Light Gull Gray on her - it's too bad there aren't any squadron markings to apply. She would look pretty cool in Wolfpack, Bounty Hunter, or Pukin' Dogs regalia - or maybe Felix on the tail. But I'm not a whiffer, so I'll be sticking to reality for the markings.

 

Cheers,

Bill

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The moment of truth has arrived! The proboscis-ectomy on the F-111.

 

Using Tommy's drawings as my guide, I measured (more than thrice!) where the cut line should be based on the length of the resin nose from Pete's Hangar. This was to ensure that the overall length of the forward fuselage would be correct.

 

I also measured the width and height of the resin nose using digital calipers. After marking the cut line,  I then measured the corresponding width and height on the fuselage. The measurements agree within 0.5 mm across the width and height cross section, but it looks like the resin nose does not follow the curvature of the cross section exactly.

 

I used 3M vinyl tape to mark the cut line:

 

IMG_1299

 

I used my CMK razor saw to make the cut, and slowly worked my way around the circumference using the tape as a guide. When completed, I cleaned up the edge with a wide sanding stick and #11 blade.

 

IMG_1300

 

The resin nose has a small step at its aft end, and this drops right in nicely. I had to tape the nose in place for the next shot, as there was nothing else to hold it in place.

 

IMG_1301

 

You can see that the fit is not exact, but it's actually not that bad. As Tommy has pointed out in his book and on his website, the actual F-111B nose joined the fuselage at a different place, and as a consequence of Pete's Hangar (and Revell) doing the conversion in this way, the contour of the fuselage (especially on the bottom forward of the nose gear) is not quite right. There will be a bit of work shaping and sanding to get the contours of the nose and fuselage correct. But I think the raw materials are OK.

 

I printed out Tommy's drawing of the forward F-111B fuselage on heavier paper, and cut out the fuselage outlines to create a sort of template. Since the paper is still a bit flimsy, it's not very precise, but it gives me some assurance that the nose is in the right place.

 

IMG_1302

 

I should have printed that out on stainless steel - it would be a much better template!   :) 

 

My next step is to tape everything together and see if I need any weight up front. I suspect not, but since there is some space between the resin nose and the cockpit, now's the time to pack it with lead if need be.

 

Cheers,

Bill

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Seeing her like that she does look completely different!

 

The shape when compared to the print out isn't that bad at all, it should be a fairly straight forward process. Once you get it done you should take a cast from the panel line just in front of the cockpit. I'm sure there would be plenty who would be keen to get their hands on a correctly shaped F-111B nose!

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20 hours ago, Graeme H said:

That back end is sure looking good, and the Rhinoplasty is coming along beautifully, this is getting very interesting 

 

2 hours ago, David H said:

Oh- Nose job looking good so far...

 

Serendipity - the nose is slightly oversize where it meets the fuselage, and this has allowed me to sand the resin to a really nice fit, matching the fuselage contours. I like it when a plan comes together. For some reason, the nose is a bit flattened on top, and I don't see this in any photos or in the available cross sectional drawings. Luckily, this can be sanded out. More photos soon...     :)

 

Cheers,

Bill

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After some time alternating between sanding and looking at reference photos, we have the initial blend of the resin nose to the fuselage. I was spending most of my time trying to make sure that the all-important slope of the nose when viewed from the side looks right, and that the slope has a slight kink right in front of the windscreen at station 180. This photo is not precisely a side view, but it shows the profile of the nose nicely.

 

project3

 

Here's where I am at the moment:

 

IMG_1303

 

IMG_1304

 

I'm happy with the top side of nose, but there is more work to do on the bottom. You can easily see that the curve on the underside of the resin nose is exaggerated, and should be smoother and flatter. This is a direct result of the way the resin conversion set was designed - I think they wanted to make it easier for the modeller to make the cut, so they made the join line vertical. (If you follow the instructions from Pete's Hangar, your cut line would be 6 mm in front of the cockpit, and that would be right on a panel line. I'm sure that was their intent. However, using Tommy's excellent documentation, the cut line is actually 8.5 mm forward of the cockpit - this ensures the overall length is correct.)

 

About three quarters of the way down this page: 

 

http://tailspintopics.blogspot.com/2009/10/grumman-f-111b.html

 

You'll see a drawing titled "F-111A vs. F-111B Forward Fuselage" - note how the actual join line follows the front edge of the escape capsule until it reaches the bottom of it, and then goes straight down. This means that the entire bottom of the forward fuselage from the front of the nose gear well was unique on the F-111B. The conversion set has you use a portion of the F-111A lower front fuselage (from the front of the nose gear well to my cut line), and this creates the issue.

 

I want to continue to work on this area until it looks more like it should. Neglecting the profile of the bottom of the nose is one reason why so many F-111B conversions that I've seen on the web or in books have a nose that looks a bit too large, and not quite as sleek as the real thing.

 

More work to do! Pass the sanding sticks, gas mask, and some single malt.   :) 

 

Cheers,

Bill

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Subtle, but noticeable, difference in the profile of the underside of the nose - don't you think?

 

Before:

 

IMG_1303

 

After:

 

IMG_1305

 

In the first picture, the underside slopes down as it moves forward from the nose gear and then starts curving up to reach the tip of the nose. This results in a more convex appearance near the join line.

 

In the second picture, the underside stays level with the bottom of the fuselage, and then starts to curve up to the tip of the nose, so it looks flatter at the join line.

 

I think it's all done except for the finishing. It's getting close, but the bottom of the radome still has too much curvature in it compared to the photo of the real thing. I've been sanding with 400 grade paper because I don't want to remove the resin too fast and go too far. Better to take my time and hopefully not mess it up.

 

Famous last words.   :) 

 

Cheers,

Bill

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Awesome job Bill, those are great reference photos (and attached blog), you can clearly see you're on the right path with the shaping of the nose.

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On 5/7/2017 at 19:26, trickyrich said:

Awesome job Bill, those are great reference photos (and attached blog), you can clearly see you're on the right path with the shaping of the nose.

 

Thanks, Rich.   :) 

 

It's been a long day of sanding and comparing to my reference drawings. I always approach this kind of job with fine grade sandpaper, as I don't want to remove too much too fast. Resin is typically softer than styrene (especially Hasegawa's grey plastic) and it's really easy to go too far without realising it. So slow and patient was the order of the day. I'm happy with the final profile of the nose:

 

IMG_1307

 

You can compare to what I started with (and the photos of 151972) and see it's pretty close. Certainly not perfect, but it will do. Besides, I'm tired of sanding it!   :)

 

I had some resin copies of the nose made before I started, and it's interesting to compare and see how much material has been removed. How much? A lot! Maybe this was the intent of Pete's Hangar - provide enough material to allow the modeller to sculpt a nose he/she likes. But I doubt it. Pete's resin nose was too big because of the decision they made about the cut line. At that fuselage station, the USAF fuselages are simply larger in diameter than the F-111B - and with a different cross section at that. I removed a lot of styrene, especially on the bottom where it's now "wafer thin." You can see the small resin step on the nose through the thin styrene. 

 

I also spent some time working on the cross sections all along the nose. The conversion nose as supplied is too flat on top, and is somewhat rectangular in cross section. The corners have been rounded off considerably from where we started. I'm really anxious to get some paint or primer on her to see how she looks. 

 

The join line between the nose and fuselage won't be the paint demarcation line (which is in a different spot and angled slightly) so I think I'll add some filler to make sure the joint is invisible.

 

The front fuselage was joined to the rear, and the base for the intakes added.

 

IMG_1308

 

I didn't bother trying to make seamless intakes, as you really can't see much in there. Plus, I'll be moving the translating cowl forward a bit. I've built this kit before (as an FB-111A) and this kit had the same oddity - the fit between the main gear bay and the forward fuselage is atrocious. It certainly looks like the two should mate, since the shape of each is the same, but there ends up being a huge gap. Luckily, the intake components hide it all.

 

The early F-111B prototypes, including 151972, did not have rotating glove vanes. I think I'll put these pieces in the closed position now, making sure that I can still add the wing later.

 

I think the landing gear is next. Ta for now.

 

Cheers,

Bill

 

PS. Thanks, Cookie! Your reply came in whilst yours truly was typing. Er, keyboarding.

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