Building the KMC 727-200 into a -100.
Author: Dan Dornseif
Submitted by: Redbelliedjet   Date: 06-25-2008
Comments: (6)   Ratings:

Building KMC's 1/72nd scale Boeing 727-200 with a -100 series conversion



Opening the Box

TWA 727This kit is a combination of injection molded styrene, and many resin parts.  The first thing that is striking is the kit’s size.  In 1/72nd scale, this kit clears two feet in length, and is really the only option for the 727, if you love large airliner models like I do.  I applaud KMC for choosing a very beautiful subject to base their first (and I think, last) full kit.

The fuselage, wings, horizontal stabilizers, and the #1 and #3 engine nacelles are injection molded, along with the windshield, nav lights, and passenger windows.  Many of the parts are also in resin, such as the inlets for the #1 and #3 engines, all three exhaust sections, landing gears, flap canoe fairings and some other sundry detail parts.

KMC 727 Parts Layout


Frankly, if one were to build this kit straight out of the box, it would be a disappointment to most serious modelers, in my opinion.  This model will require a lot of work to make it accurate, but it can be done.  There are some significant fit issues, and some sink marks in the fuselage which need to be reworked.  I will present the kit’s problems, and solutions, as I walk through the construction step by step.

The Build

Having already built this kit a few years back for a good friend’s retirement present, I was looking this time to truly correct the issues, and to convert this series -200 kit into an accurate -100.  The goal was also to scratch build the flaps and slats, having the landing gear “in transit”, while sitting on a stand.

I will start with the fuselage.  There are parts of the fuselage which are accurate, such as the wing to body fairings, and the general shape of the aft fuselage.   However, the nose section in very inaccurate and crude.  The taper of the fuselage towards the nose is too abrupt, and should start farther back on the fuselage.  The windshield is too small,  and from the front, the lower part of the nose section is too square in appearance.  The vertical stabilizer looks good from the side, but the trailing edge is too thick, and needs to be sanded to more of a point.  This required the rudder to be re-scribed later on.

Firstly, the nose section will need to be addressed.  I felt there were two options.  The first, would be to fill the nose section with resin, and then re-sculpture the nose section to the proper shape through hours of sanding and rechecking (this was the method which I utilized in my first KMC build).  It works, but takes a lot of time and patience.  The second option is to use Authentic Airliner’s beautiful resin nose replacement, engineered specifically for this kit.  It is exactly the right shape, and fits the model very well. 
Authentic Airlines Replacement Nose SectionThis is Authentic Airliners’ excellent replacement nose section applied to the model.  It is super accurate!
The scratch-built extension of the wing-to-body fairing can be seen.  Note the excellent reverser detail of the kit’s Pratts, discussed later in the article. 
KMC 727-200 and -100 ComparisonThis picture illustrates the differences between the stock -200 kit, and the -100 with it’s modifications.


Shortening the Fuselage

To shorten this model to a -100, two fuselage “plugs” must be removed in order to achieve the proper length.  This would equate to removing six windows from in front of the wing, and another six behind the wing.  I began with the aft section for a reason which will become evident shortly.  I removed the plug directly behind the trailing edge of the wing, where the fuselage taper is still at a minimum.  Unfortunately, in doing this the aft section of the wing-to-body fairing went with the removed section.  This was corrected by adding sheet styrene, cut to correct shape, installed, and then sanded down to properly blend with the rest of the fairing.

Once this was complete, I was able to calculate the scale length of the model, and then taking into account of the length of the resin nose replacement, establish exactly where to cut the fuselage for the nose join.  Referencing the left side of the model’s fuselage, this calculated out to be between the 10th and the 11th passenger window referenced to the left side for a -100 series, and or between the 4th and 5th windows if you were building the -200 aircraft.  Prior to adding the resin nose section, I added some epoxy to thicken the walls of the resin nose as it is hollow, and somewhat thin.  This will allow you to sand freely later to contour the join, without worrying about sanding all the way through the material.  Once this was complete, a lot of sanding and filling with gap filling CA glue was required to make the joins invisible on the finished model.  It is noteworthy that  the directions dictate that no nose weight is required.  This is not correct.  You will need it, and quite a bit of it to counterbalance the resin engine parts on the tail end.

The 727 has a set of inboard main gear doors, which are open only when the gear is in transit.  Therefore, there was no need for the kit’s manufacturer to provide the entire main landing gear well in the kit.  However, since I was modeling the kit with the gear swinging, this would have to be built from scratch.  I “borrowed” a few parts for an old KC-135 kit, and used various types of corrugated sheet styrene to build the compartment.  At that time, wiring and other details were added to make it look satisfactory.  Behind the rear bulkhead of the main gear well, I installed the receptacle for the stand, using brass tubing, and lots of glue to reinforce it.

KMC 727 Gear Bay Details


Other Modifications

The other modification which was required, was to the #2 engine inlet.  On the -200, this inlet is perfectly round, but on the -100 it is taller, and ovalized.  I cut off the top half of the inlet, and inserted strips of sheet styrene, in order to achieve the correct inlet profile as viewed from the front.  Once the was complete, there was yet more filling and sanding to contour it into the tail section.  I used a Dremel tool on low speed to sand and shape the inside of the inlet.

The side mounted engines were one of the highlights of the kit, with excellent reverser details, although a look up the tailpipe reveals turbine details which are too close to that back of the jet pipe, to the extent that it is also aft of the reverser cascades, which is incorrect.  However, this was one inaccuracy which I chose to ignore.  This required more CA glue and sanding to blend everything together.  The fan detail in the inlet fit nicely and looked fairly good (although, stator vanes would have been nice), so I deemed that the engines could be built without modification.

The wings and the vertical stabs were done quite nicely.  The panel lines are recessed heavily, but are true to the actual aircraft.  The wings, I felt were a bit thick as viewed from the front and required some sanding to thin them out before the halves were glued together.  One slight omission on the wings, is that the stall fences are not represented, and must be made from styrene.  Since my model was to have the flaps set at position 5 (takeoff flap setting), I cut out the flaps sections from the top and bottom of the wing panels.  I became concerned about the integrity of the cut wing, so a small metal wing spar was added.  The leading edges were sanded down in order to appear that the slats were extended.

With all of this being done, the wings, horizontal stabs, and engine pods were added to the fuselage.  Once again, fit was a major issue, and copious amounts of CA glue and sandpaper came to the rescue.  Some modelers prefer not to add components like engines and stabs until after painting, but with the kit, I would very much recommend that these fit issues be dealt with prior to painting.


The Finish

I elected to finish my model in Trans World’s twin stripe livery.  The deletion of the black anti-dazzle paint in front of the windshield, would suggest that subject aircraft would be nearing it’s retirement from the fleet.  I decided that I would like the paint on the fuselage to appear freshly applied, however, since TWA did not paint the wings like most other carriers, the metal parts would likely be stained from years of use, and hydraulic leaks would tend to be abundant.  I used Model Master Classic White for the fuselage, Model Master primer to represent the corogard inspar area, while using Alclad II for the metal panels.  For many years ATP sold a very nice TWA 707 decal in 1/72 for the Heller kit.  I used this decal for the “Trans World” titles, and modified the stripes to fit the shorter 727 (they fit the -200 almost spot-on).  If you choose to use these decals today, I would recommend clear coating them first, to prevent them from breaking apart, due to their age.  With the red color matched, I painted the red field on the tail, then used clear decal, painted white and cut to shape to represent the “TWA” titles.  The windows are my favorite part of the finished model.  I used the windows from TwoSix Decals’ 1/72nd scale PIA B-707 sheet. The representation of the window on the decal really looks three dimensional, and has the window shades in various positions, which gives a very realistic effect.  The livery was finished off by using Avigraphics 1/72 727 detail sheet which is quite nice. 

KMC TWA 727The landing gear is a very sore spot on this kit in my opinion.  They are quite detailed and accurate, but they are extremely brittle, and have very little structural integrity.  My first KMC build, sat on the kit’s gears, and to their credit, they have never broken, but I was always very careful never to give them a hard landing on the shelf.  On this build, however, I would pay little attention to this problem since it would be on a stand.

Since the flaps were to be modeled in the takeoff position, these were scratch built out of sandwiched layers of sheet styrene, sanded to shape, then glued together to represent the triple slotted Fowler flaps that the 727 has.  The leading edge slats, and Krueger flaps were made in the same manner, and glued to the wing.  Weathering of the wing was accomplished using a dark grey acrylic paint, watered down and mixed with dish soap.  This mixture allows you to apply it heavily to panel lines, then wipe the excess off to create depth, hydraulic streaks.

TWA 727 Taking Off

Conclusion

In conclusion, I would highly recommend this model to a modeler who loves the 727, and enjoys a challenge.  I am quite happy with my model, and I appreciate it more perhaps, because it was so much work.  Although I spend most of the article, explaining the faults of the kit, It does have some very good parts too.  The wings and most of the fuselage are reasonably accurate, as is the landing gear.  The kit decals are quite nice, and depict an American Airlines (red, white, and blue) scheme.  Other than a very inaccurate vacuform kit from years ago, it is really the only game in town in 1/72.

Since KMC went out of business soon after this model debuted, you will have to resort to eBay and like to find an example.  They surface frequently.  Originally, the kit was $ 65 new back in 2000.  Now it tends to fetch anywhere between $ 100 to $ 200, depending on where you look. 

I hope you will enjoy building this challenging kit as much as I did.


by Dan Dornseif

Member Comments :

comment by: gebbw posted on 06-26-2008 #6059
Thanks for the great article Dan, and a nice build. I've had this kit in my pile for some time now and also plan to convert it to a -100.

regards
George
comment by: Redbelliedjet posted on 07-06-2008 #6259
Thanks George!

Kurt's nose section is the key with this model. Go for it! What airline are you planning? My next KMC will be a PSA -200.

Cheers,

Dan
comment by: Kev1n posted on 07-26-2008 #6375
Nice work on this....I'd love to have a go ay a KMC 727 as it's one of my favourite aircraft....I especially like the last pic of it flying off into the sunset.
Actually I like it so much I nicked it and put a copy here -
http://www.bebo.com/modelkitbuilders
on my own site, with due credit to you as it's your model.
I did take the stand out tho...a little bit of subtle pic editing
Hope you dont mind
comment by: Redbelliedjet posted on 08-05-2008 #6501
Hi Kevin

Thanks for your kind words and including my model in your site. You did a great job getting rid of the stand! You should have a go at the kmc. It was fun!

Cheers,
Dan
comment by: Kev1n posted on 09-30-2008 #6805
I'd love to...except for asking myself....where will I put such an humongous sized model...I'm pushed for space as it is

btw...did you take a copy of the altered pic from my site? You should be able to - editing out the stand is easy really
comment by: Redbelliedjet posted on 09-24-2009 #8561
That's why I made it a -100 :-)