First attempt to kit bash a 1/48 UH-1F Huey

I contacted the USAF Museum in Dayton about the markings on their UH-1F...Please NOTE: we had NO insignia of any kind except for a Green Hornet on our tail booms; we flew with no insignia on us in and out of Cambodia and Laos; we were young; wild and stupid; but I served with the Greatest group of People in the world...the Green Hornets.

P.S. The USAF took all the insignia OFF their display model and painted Green Hornets on the tail boom...all the BEST; GREAT modellers in here;

P.S. 2 I was Great Friends with lst LT Jim Fleming; the Pilot who got the Medal of Honor; you will never meet a finer man!

Thanks so much!

Rob Combs

Louisiuana

I know it's been awhile but what ever happened to this super build?

I was trying to follow the above conversation about building the Bell UH-1F.  A lot of problems though...the PhotoBucket photos were unlinked, the thread was pretty old, and for whatever reason, no one seemed to finish their projects.  So I decided to give it a try.

I'm not a prolific modeler, although I have kit-bashed and scratchbuilt some structures and rolling stock in HO scale model railroading.  I decided to tackle this job in 1:48 scale, since it was larger, and the models required for kit-bashing are readily available.  After some thought, I opted to use the Revell UH-1C "Huey Gunship" and the Italeri UH-1D Iroquois (shown here).

As previous authors have noted, the UH-1F was the USAF version of the Bell UH-1 Huey, which was already in use by the US Army (UH-1B,C,D,H) and US Marines (UH-1E).  The UH-1F model variation was developed by Bell to US Air Force requirements to utilize the short UH-1 cabin with the larger engine being used in the Sikorsky CH-3 Jolly Green Giant helicopters, primarily because the USAF had already purchased warehouses full of that engine.  The larger engine not only had more deliverable power, but also greater torque.  Bell solved the torque issues by increasing the length of the main rotors from 44' diameter to 48' diameter to dampen the torque stresses.  Increasing rotor blade lengths meant lengthening the tail boom to move the tail rotor beyond the main rotor disc (my guess was at least 2 feet).

The UH-1B/C models Huey are built with the 44' main rotor, short cabin, and short tail boom.  The UH-1D/H models Huey are built with the 48' main rotor, long cabin, and longer tail boom with a cubby hole on the starboard side.  Tail rotors are 8' diameter on all models.  And so these models seemed to be the obvious choice for kit-bashing subjects for a UH-1F build.  Now here's where the differences with previous authors piqued my curiousity in this plan.  It was presented as straightforward to use the 48' diameter rotors from a UH-1D kit with the short UH-1B/C cabin and the longer tail boom from a D/H model.  However, after acquiring the 1:48 models and laying them out for the planned surgery, I determined that straightforward it was not.  See below.

Placing the two fuselages above and below on 1/4" graph paper shows some troubling observations.  The main rotor from the Italeri UH-1D (48' rotors) are placed on the UH-1C rotor head transmission.  I had previously severed the UH-1D tail boom (lower) and placed it back in relative position for the photo.  As can be seen, the tail booms on the B and D models are virtually the same.  Also, you can see that the longer main rotors on the B model (above) would cross the arc of the tail rotor, not good!  It became apparent that some of the lengthing of the UH-1D/H had occured with the lengthening of the cabin.  Remember the rotor transmission juts into the rear of the cabin, surrounded by a cabin bulkhead.  And so, the common concept that a D model tail boom transplant to the B model cabin would equal an F model proportion is not accurate.  Therefore, some more surgery will be required.

My solution to the problem was to splice some more length into the UH-1C tail boom, thusly:

Using the tail boom from both models to splice together a properly proportioned boom for a UH-1F seemed to be the best solution.  Previous authors noted the differences in countours and thickness of the booms between the Revell and Italeri kits.  The Revell tail boom is thicker, more rigid plastic with a more squared-off contour shape, whereas the Italeri tail boom material is thinner, more flexible, and has a more ovoid contour shape.  So I decided to keep the forward boom of the Revell UH-1C kit, and use the aft part of the Italeri UH-1D kit to add to the length of the boom.

This photo shows about where the cut was made.  The aft part of the boom measures about 3 inches, and the forward boom about 2 1/4 inches behind the cabin.  This cut point is purely a guesstimation based on the top and bottom lines of the boom.  At this point there was a lot of sanding and trial fitting to attempt to match the contours.  The inside edges of the Italeri boom had to be sanded to make a "thinner profile" to try to match the Revell contours.  All I can say here is sand and fit, sand and fit.

I used a portion of the Italeri boom forward of the cut to insert into the Revell boom as a strengthener, extending about 1/2" on either side of the cut.  Although epoxy might have been better, I used thick CA to hold the reinforcing insert and to join the two boom parts.  Tamiya putty on the boom and tail rotor shaft housing helped hide the cuts.  Lots of sanding and filling to make it look as best I could. 

Since I didn't use the forward part of the Italeri boom, I missed out on gaining the already modeled storage cubby on the right side of the boom.  So I traced the contour of the door from the Italeri kit, transfered same to the Revell boom, and cut a hole for the door.  I made a new door from styrene to fit the hole.  I used thin styrene strips on the inside of the cubby to resemble boom support stringers between the bulkheads, painted the area interior green.  I will be using this model on a diarama, and the cubby door will be open.  I'll use small strips of brass to represent the hinges.

The other major surgery is previewed in the above photo by the obvious insertion of the rear part of the engine.  More about that in another post section.

As previously stated, the engines in the UH-1F were larger, and the transmission/shaft connections required Bell to rework the engine configuration.  The result was ducting and baffling to bring air into the engine from fore and aft.  Forward of the rear clam-shell engine cowling hinges, the external appearance of the engine compartment is much like any other UH-1B/C model.  But aft of those hinges, the differences are obvious.  Refer to the photos above.  The engine exhaust is vented to the right side of the engine compartment, while the left side of the cowling is distinguished with a large egg-shaped screened intake area.  These features are unique to the UH-1F among Hueys.  Note the location of the cubby storage area on the starboard side of the boom (left of the airman's elbow).

Since no manufacturor makes a 1:48 UH-1F, nor are there any upgrade parts available for this variation, I was tasked with making my own.  I had been interested in learning to make my own molds and casting for some time, so now seemed as good a time as any.  I had purchased suitable materials, and began by making a mold of the original Revell UH-1C model.  I used some of the Lego blocks left in my attic by my kids to make a walled-in reservoir and dam to contain the molding material.  I taped the model halves together, used modeling clay to plug the inside area to prevent getting much of the molding material into it, and used modeling clay to creat a dam between the Lego blocks and the outside of the model's curved surfaces.  Placing the model in the Lego reservoir, I was ready to pour.

The molding material is a two part silicon gel that is fluid for about 15 minutes before starting to cure.  Following directions, the pour was completed and allowed to set.

Lessons learned:  Silicon molding fluid is very viscous and if allowed, will find a way to leak through.  The modeling clay was not totally effective in preventing the material to leak into the model, and potentially more serios, through the Lego reservoir.  Fortunately, I had placed the entire operation into a disposable baking pan, so nothing went farther than that.  The leakage into the model was easy to remove making clean-up a non-event.  In the future, I used clear food wrap (Saran) to line the reservoir and contained the leaks.

Next, I used a two-part urethane casting material to make a mold of the original UH-1C enging section.

I forgot to add that prior to molding the UH-1C model I had place some modeling clay around that aft portion on the engine to allow material for carving the new engine shapes.  Above is the later smaller casting that emerged.  After filing and contouring and comparing the new shape (did I mention repeatedly?) a recognizable contour began to take shape, and I drilled a hole where the exhaust would emerge, and added a blob of clay where the egg-shaped air intake would be.

At this point I was ready to make another mold and casting...

Here is the result of the second casting fitted onto the UH-1C model after some amputation.

Now the process of putty, filler, sanding, contouring, glueing....repeat.  Athough there are warts and freckles and scars, I am pleased with the result.

I used Archer grid surface detail decals to bring out the screened effect of the air intake.  The exhaust pipe is a contoured soda straw, trimmed and inserted into the hole, glued, and painted.

This is very much still a work-in-progress, so the roof, nose, skids, FFR pods, rotor head and rotors are not glued on, but mocked-up for the photo.  I am presently building a pair of M134 miniguns to be mounted on either side of the cabin.  Sadly, I purchased miniguns that did not have any sort of gun mount, so I am in the process of scratch building those tiny, teeny, did I say very small parts.  Wish me luck and I may actually finish this build.

Hello!

Lookin' good! I have to tell you, you'd be better off if you didn't reply to threads that are years old, but instead if you started new thread for yourself.

Anyhow, nice scratchbuilding, good luck with your build and have a nice day

Paweł

Hello sirs.
I also began has to look for all that it is necessary to make one but in 1/35. I am lost, I know not which length to cut and or to make him(it). Here are the photos of what I possess to build him(it) .et the brick-built lego mold for the hood of the engine.

 phil .

Phillipe,  It looks like you've already gotten the basics for a 1/35 Bell UH-1F/P build.  And you've already started to figure out the challenging issues with the build itself:

1. Molding and casting the F-model engine housing with the bulbous intake screen on the port side of the cowling and the starboard side engine exhaust pipe.  That will take molding from the C-model canopy, adding some substrate to the outside to allow for material to carve into shape, and recasting of the replacement part in resin or similar material.  Greater proportions due to scale may allow you to bring out details.  I did a Google search for the MRC 1/35 UH-1C and found that there is an Eduard detail kit for that model.  It may be worthwhile to see what comes with that kit.
2. The rotors are straight-forward.  Swap the D-model rotor head and rotors over to the C-model cabin and transmission.  You may have to do some tweaking on the rotor head to transmission attachment parts, especially if you want the rotor to turn on the finished model.  On mine, it wasn't a priority, but I did have to match the hole size of transmission head to the rotorhead insertion.  The original C-model rotors were 44' in diameter.  The D/H/ and F-model rotors are all 48' in diameter.  By switching the D-model rotors to the C-model cabin you have set yourself up for the F-model.  Since the increase in rotor blade length (not diameter) is 2', I reasoned that the tail boom had to be lengthened by at least 2' for the tail rotor to clear the main rotor.
3. Where to cut and splice the tail boom?  For the 1/48 models I used (above), I used calipers to measure the boom thickness behind the storage compartment door located on the starboard side on the D-model and absent on the C-model.  If you are lucky, you can find the location somewhere aft of that location where the materials and dimensions of the two booms is about the same, which will make it easier to hide the cut locations.  Note that the full tail boom length of the C and D models are actually about the same.  That's where your best judgement of where to cut the aft section of tail boom comes into play.

Use your reference photos as much as you can.

I decided to make mine a gunship with M134 miniguns mounted in the doors.  I did find aftermarket miniguns in 1/48, but no mounts for them.  To you advantage, I understand that there are very nice aftermarket parts for these guns (including the mounts) in 1/35.

Let me know if you have any questions about what I have done, I will be glad to help.

Hello jmoran426.
Thank you for your answer, at the moment, I have has little near everything and I have to find a photo of the blade of rotor which heavy arty had put on a discussion saying that the width of blade were not good on the dragon and saying that it was necessary to cut an end on all the length, here is the photo:

 The red party would be has to remove .

Just saw this.  Yes, the blade as it comes in the Panda/Dragon UH-1D/H kit is actually a UH-1N/Bell 212 blade.  In the pic below, the center blade is how it comes in the kit.  The bottom blade is marked in red for what needs to be removed.  The top blade is the corrected blade after the excess spine (red) is removed.  If you can find the Dragon UH-1D Heer kit, it has the correct D/H blade.

Hello heavy arty.
I am going to correct the blade because the huey is D that I bought second-hand knowing that I was going to cut it . Thank you for re-specifying what to do, seen that I rappellais me more for that of it HEER.

phil.

Here is a reference image I used to sort out measurements and differences.  The image refers to the UH-1B and C model cabins.  The F/P model image is superimposed behind it for length comparison, and the rotor masts are positioned on top of each other to show the length of rotor comparison as well as the location of tail rotor.

Hello the guys .

here is what I understood and what I cut but if I take he tail of H , the trapdoor of the right -hand ide does not fall at the right place but I'm going to play with putty and plastic card . I converted in metric system and that give me 16,98 cm . for against , t the level of the rotor anti-couples , the part of the end of tail is not the same , I resume that of C , then ? 

phil .

Yes, I would agree that you should use the C tail as the base.  The H tail boom will have to be modified by covering up the storage cubby hole and recutting it into the base of the C boom base.  I had to do same.  My cubby did not turn out as large as H model, so you may be able to be more generous in its dimensions.  Use the storage cubby door as your template for the new hole and frame inside with plastic card and other strips.  I'll try to post a photo of mine.  Your cutting dimension looks good, just a lot of putty and blending with sanding to make it look correct.

Hello jmoran426 .

Here is what I made on the half-fuselages and the cut for the safe(chest) has luggage, and the cut of the driving hood, little of miliput to shape the good driving hood .je am me to serve as paper traces to stick on the screen of my computer to make me a template  evergreen.

 phil .

Hi ;

 Some of you fellows and ladies are using a photo site I cannot click into . What gives ?

Hi TankerBuilder .

You cannot see photos? Host photo is SERVIMG.

sorry that you do not see them and I understand not why.

 phil .

Hi gentlemen .

the yellow part comes out to being able to shape burn out her in PE . I began the safe has luggage , to delete the parts too on the blade of rotor , and to change the empennage on the tail of H by serving me as that of C .

 phil