1/10 Revell Allison Turboprop Engine (modernized and converted to C-130E/H spec)

[zibbit]

Hopefully this model is allowed here.. it really doesn't fit anywhere else.

 

Ok here's my take on an old box 1/10 Revell Allison Turboprop model, box art is as follows;

 

I found it funny that Revell chose to put a C-130 on the cover; it was probably a marketing strategy to sell more kits because of the cool factor associated with the Herc.  However, if you build it as-per the instructions, you end up with a model that's no-where near the resemblance of a Herc engine.  That's because the model is actually a very early generation of the T56/501 engine lineage (T56-A-1 or 501-D13) which was found in the Lockheed L-188 Electra.  So, if you want to build a P-3 Orion/CP-140 Aurora engine; build it as-per with light modifications.  Whereas if you want to build a fairly recent C-130E/H running a T56-A-15; you've got a LOT of work ahead of you.

 

I picked up the kit pre-owned from the local hobby store, and just from years of sitting on someones shelf or being handled; 95% of the parts broke away from their sprue. 😒 Imagine the look on my face opening up the box and seeing a limp bag of 205 VERY similarly looking parts sitting in a heap.  As you probably know, instructions were a guessing game in the 90's with crudely drawn sketches that are almost impossible to understand (I hear Atlantis has addressed this issue), and to cap it off the one of the driveshafts going from the front frame to the gearbox was missing.

 

New plan.. replace three-piece plastic driveshaft with a one-piece metal driveshaft.  Then.. the modifications started snowballing from there.

 

Modifications I completed (prop to exhaust).

1. Gearbox

a. drilled mounting nacelle mounting points.

b. flipped gearbox

c. metal thru shafts for spur gears

d. metal hinge pin on access door (common to break in factory form)

2. Front frame

a. relocated gearbox support strut mounts on front frame

b. added pressure sensor port in 9 o'clock inlet guide vane

c. relocated PLC feedback linkage-arm-hinge to account for flipped gearbox

3. Compressor case

a. drilled compressor spool core to account for new driveshaft

b. created the new compressor-air bypass ducts

c. created most of the air line plumbing using either stretched sprue or .020" safety wire

4. Mid-frame (diverter)

a. redesigned QCU airframe mounting flange

b. added 1 & 11 o'clock customer bleed air ducts

5. Combustor case/access door

a. ran two ignitor leads to proper boroscope port (kit had location wrong)

b. drilled dilution holes in combustion cans

c. created Turbine inlet temperature sensor loop

6. Rear mount

a. made exhaust cone able to rotate engine driveshaft instead of using thumbwheel for a more scale appearance.

7. Accessories

a. created a new stand to support the new configuration of the model.

 

*if I messed up with my terminology regarding T56 turboprops, please feel free to correct me.  I'd rather have a correct post, than an incorrect one.  My background is F404 engines (F/A-18 Hornets), so I may be incorrect with some Hercules stuff.*

 

Because not everyone has experience around turbine engines.. here's a pictogram of the locations I modified according to the previous list.

 

And, the rest of the pictures...

 

 

 

 

 

 

 

 

 

 

Edited February 20, 2021 by zibbit

[Jackson Duvalier]

That's a well-executed model of an offbeat subject, zibbit.

[zibbit]

Thanks Jackson.  Makes me miss putting together CF-18 engines for a living..

[Britman]

That's very impressive and something new to me  given that I have a few hours on the clock!

 

Keith

[Pete in Lincs]

A real beauty built by a bloke who knows his stuff. 

[SAT69]

You've done very impressive work!

[Spitfire31]

That is a fabulous piece of modelling – a real museum piece!

 

Also, a very interesting aeronautical subject among all the Bf 109:s and Spitfires…

 

Great, dedicated work!

 

Kind regards,

 

Joachim

[Jay Gee]

Excellent work zibbit, great modelling!

 

This brings back a lot of good memories, aaaaaand not so good ones either Night shift during winter time and being elbows deep in the engine is the first thing that comes to mind.

[noelh]

Well as someone who spent 14 + years years involved with jet and turbine engines. I tried really hard to fault your build. 

I failed. 

What I really like is that most of the terminology you use is familiar to me. 

For once I understand it. 

 

Already I see others have been there. 

 

Aeroplanes are the glamorous side but without us powerplant people nothing flies. 

[dnl42]

Wow, that's a truly outstanding model! 

[zibbit]

5 minutes ago, noelh said:

Well as someone who spent 14 + years years involved with jet and turbine engines. I tried really hard to fault your build. 

I failed. 

What I really like is that most of the terminology you use is familiar to me. 

For once I understand it. 

 

Already I see others have been there. 

 

Aeroplanes are the glamorous side but without us powerplant people nothing flies. 

 

Haha.. sometimes it's fun to shop-talk.  I used to think building a full size turbine was challenging.. until I tried to build one 1:10 scale.  The parts are SOOOO small.

[k5054nz]

I've been tempted to find a cheap one of these kits, or the Atlantis repop, but now I'm not sure I'd be satisfied with my skill level. Wow. Utterly stunning work!

[noelh]

20 minutes ago, zibbit said:

 

Haha.. sometimes it's fun to shop-talk.  I used to think building a full size turbine was challenging.. until I tried to build one 1:10 scale.  The parts are SOOOO small

Shop talk, yes it's so long ago now, 1994. I wasn't a mechanic, just engineering support but I knew every detail. The complexity of a turbine engine, the tiny measurements and clearances 

 

In 1/10, micro. 

Edited February 21, 2021 by noelh

[zibbit]

2 hours ago, k5054nz said:

I've been tempted to find a cheap one of these kits, or the Atlantis repop, but now I'm not sure I'd be satisfied with my skill level. Wow. Utterly stunning work!

Quite literally it was the most enjoyable, frustrating and rewarding model I've ever built.  haha

 

If you want less frustration, just get the new Atlantis kit.  At least the instructions will be better, and you can only hope that the molds are better maintained.

Edited February 21, 2021 by zibbit

[stevehnz]

You don't see one of these every day! That is a bit wonderful, the sort of thing we've all seen but never understood 'cause we didn't need to but from living under Electras droning their way to Aus as a kid, to thrilling to C-130s & their antics, I really like this, it is nice to see flesh put on the legend.

Steve.

[Space Ranger]

Excellent! Looks like a real engine. The Atlantis re-release relies on the original Revell instructions, which are much better than the simplified ones in the Revell re-release.

[Harold55]

Wow is right!  Incredible job and I really appreciate the detail on your modifications.

[The Rib Man]

That is a really cool build.  I have recently been pouring over the F-111's on the National Museum of the USAF virtual tour page, and interestingly there is a C-130 turboprop on display with a gunship right next to the Aardvarks and Tornado.  It is an earlier model, but you have really captured the look of the engine.  It is great.

 

RM

[Gary Brantley]

"Fire it up!"    Fantastic modeling, and wonderful realism...

[Sabrejet]

That is very nice: I have about 10 years working on these and your model is hard to fault!

[Bell209]

As one old C-130 maintainer to another - well done, Sir! 👏 An excellent representation.

[DMac]

zibbit;

Thank you for this wonderful information.

I just acquired the Atlantis version of this kit and I was hesitating because I knew it was not right for a Herc.  Your timing and display is perfect.

The first change I saw to make was replace the 3 plastic shaft sections with a single brass one.

I wonder if you would be willing to share some of your tips during construction.  For example, how you managed assembly using only a single shaft?

I am not near as familiar with the hidden details of the T-56 as you would be.  As an old Herc driver, we depend on people like you to keep us moving.

Thanks again.

 

[Space Ranger]

I'd b grateful for some tips as well. For example, did you replace any of the molded fittings with after-market parts?

[zibbit]

On 09/03/2021 at 10:13, DMac said:

zibbit;

Thank you for this wonderful information.

I just acquired the Atlantis version of this kit and I was hesitating because I knew it was not right for a Herc.  Your timing and display is perfect.

The first change I saw to make was replace the 3 plastic shaft sections with a single brass one.

I wonder if you would be willing to share some of your tips during construction.  For example, how you managed assembly using only a single shaft?

I am not near as familiar with the hidden details of the T-56 as you would be.  As an old Herc driver, we depend on people like you to keep us moving.

Thanks again.

 

 

Essentially to run a 1 piece driveshaft, you're going to need to build it from the back-end of the engine systematically moving forward in small sections.  I'm not going to lie, it was a huge PITA trying to figure out what could be glued together or assembled off the model, and what needed to be glued on the model.  A LOT of time spent dry fitting items together to see if an assembly could be built before installing it on the engine.  Not to mention but you need to drill out any and all sections that coincide with the specific size of the driveshaft you chose.  Anything that rotates with the driveshaft you're aiming for a snug fit, anything that stays stationary with respects to the driveshaft needs a looser fit to allow some lube to keep items separated.

 

From trial and error the assemblies that I found could be pre-assembled OFF the model were:

-Combuster section inner core with cans

-Midframe & diverter

-Compressor Spool (part that rotates)

-Turbine spool (part that rotates)

-Center section of the reduction drive gearbox with the planetary gear and large 

 

Assemblies that MUST be assembled ON the model:

-All exterior cases (compressor, combuster case, etc)

-Everything else.. lol 

 

From trying to remember how I did it, I believe the coles notes go something like this:

1. Glue Turbine spool on driveshaft, make sure enough of the shaft protrudes from the back of the engine to clear the exhaust frame rear support.
2. Slide Exhaust frame (rear support) into position.  Lube the contact point.
3. Slide combustor core on the center shaft far enough to align with the exhaust frame, turbine spool, and wide exterior case.  Lube any contact points near the front of the turbine spool and/or midframe.  Carefully glue the comb. core to exterior case, and comb. case to exhaust frame; take care you don't get any glue on the turbine or driveshaft.
4. Install all 3 stages of Turbine stator blades into exterior case.  You need to modify each stage to remove alignment pins so they'll slide in the channel.
5. Install skinny exterior combustor case
6. Mount midframe & diverter
7. Install fuel nozzles into midframe/combustor cans
8. Slide compressor spool to the main driveshaft.
9. Install both stationary compressor cases (without the stators installed YET)
10. Install Inlet guide vane (only full circle stationary blades) & inner section
11. Install front frame.
12. Glue compressor spool after aligning it with channels in compressor case
13. Install the compressor stator into their respective channel.  Again you'll need to remove all alignment pins so they'll slide into the channel
14. Install power take-off shaft cover.
15. Install rear case of the reduction gearbox, glue the drive gear into place.
16. Install reduction drive center section and access door
17. Install outer planetary gear drive into forward gearbox case
18. Install front gearbox case

 

22 hours ago, Space Ranger said:

I'd b grateful for some tips as well. For example, did you replace any of the molded fittings with after-market parts?

 

If you're building the model as an A-01, using all the exterior duct work, then all of the lines from the kit will work and are pretty accurate.  If you're modernizing and flipping the gearbox like I did, you're gonna need a lot of reference materials.  Most of the lines from the kit were cut to remove the fittings; then replaced with brass tube or steel wire.  I found searching for hercules engine static displays to be especially helpful.  I know there's a couple high resolution photos of an A-14 cutaways on the inter webs.

[Space Ranger]

Many thanks for those tips.