Sunday, August 31

Gary's build of the 48th scale F-15DJ Eagle from Great Wall Hobbies - Part 2

Gary Wickham continues to tackle the already very good F-15 Eagle from Great Wall Hobbies in pert two of this build in which he is just about to make this kit even better..
The Build (continued)

It’s not often that I find myself intentionally removing detail from a model but in the case of the canopy framing it looks like GWH were basing this part off photos of F-15E Strike Eagles. The Strike Eagle has additional cooling ducts/piping fitted to the framing to support the enhanced Environment Control System (ECS) requirements to cool the additional F-15E cockpit avionics. A sharp knife and sanding stick made quick work of removing these to accurately represent an earlier F-15D.
While I was working on the framing and looking at reference pics I could not help but notice that the hinge point for the main canopy strut was woefully under detailed. A few mins and several cents of plastic card resulted in something a little more interesting (and accurate of course). I added a couple of rows of Micro Mark raised rivet decals for good measure.
A before and after comparison of the canopy framing. Little touches like this are quick and easy. 
Normally I would just hand paint the cockpit side consoles but for some reason I decided to mask and airbrush the Tamiya XF-85 Rubber Black. The detail on the GWH plastic parts is very good and I see no reason you would need to swap this out for a resin set (even if one was available)
Like the cockpit tub, the instruments panels are very nicely done. As I am modelling a current (2013) JASDF F-15DJ I chose the post MSIP panel (GWH provide both pre and post MSIP panels). MSIP introduced a new Programmable Armament Control Set (PACS) in the mid 1980's. This featured a new MPCD (Multi-Function Color Display) in the front cockpit left side panel.
The HUD frame is provided by GWH as photo etch in the kit (nice touch). One thing missing that I felt the need to add was the HUD camera. This was easily built from some plastic card and lead wire. 
At the last minute I decided that the kit supplied oxygen hoses were not up to the task and created two of my own from copper wire. The comms cable was added from 0.3mm lead wire held on with small strips of Tamiya tape. I'm glad I did this as they look much better than the plastic parts.
The completed front tub. I really like that GWH provide the cockpit instrument dials as individual decals. I know it’s more work but the end result is so much better than one big decal. As usual I have hand painted all the details with Vallejo, applied a wash of Model Master Raw Umber and dry brushed with Model Master Chrome Silver.
The rear tub in the F-15B/D is pretty sparse (unlike the later F-15E Strike Eagle). Mainly occupied by flight instructors or passengers only basic flight instruments and controls are present. 
An overall view of the completed cockpit tub with the front and rear shrouds in place. Being the first time I have used the Model Master Raw Umber enamel paint as a wash I am happy with how it gives a dusty/grimy look to the black parts in the cockpit. 
With all the detailing work now complete on the fuselage interior I was inching closer to closing it all up. I was quite concerned about this model being a tail sitter. Normally you would just fill the radome and fwd fuselage up with as much lead weight as will fit but with my decision to display the radome and avionics bays open I was scratching for space into which to glue some weight. In the end I think I found enough nooks and crannies into which I could stuff fishing sinkers into (fingers crossed).
With the fuselage now joined it was time to figure how to attack the open radome compartment. The kit includes a large lip into which the bulkhead is mounted. This is simply not present on the real F-15 and once I noticed it I knew I would not live with it being there. My solution was to cut away the kit lip and glue on my own 10 thou plastic card bulkhead. I still needed to represent the actual sheetmetal lip which in scale terms is about 1mm in size. I needed a material that was strong, had the scale thickness of sheet metal and could be bent to match the curvature of the fuselage without breaking or kinking. The one material that I know which meets all these requirements is sheet copper. I cut a 1mm strip and used the radome to curve it roughly to shape. This was then progressively glued (using CA) to the edge of the fwd fuselage. When dry it was sanded (another benefit of copper) and putty used to remove the seam.
With the new bulkhead in place I next thinned down the kit bulkhead part (C32) so that it was as thin as paper (it was literally translucent). This was laminated onto the new plasticard bulkhead. The next challenge to be tackled was to make a sturdy mounting point for the radome hinge. This needed to be strong enough to fully support the weight of the open radome part. I cut off the hinge mounting point from the kit bulkhead, moved it closer to the edge and combined it with some plasticard supports to raise it up and give more strength. The radome hinge was likewise enhanced with card and finally three lengths of 15 thou brass rod was mounted into the radome hinge with corresponding mounting drilled into the bulkhead mount point. So far the strength of this solution seems to be good but we'll see once I start to transport the model in the car etc.
With the front of the model under control it was time to switch gears and move to the very backend. I decided pretty early on that the kit nozzles, whilst nice, had some over scale parts (the nozzle actuating rods mainly). I happened to have a spare Aires F-15E Nozzle set in my stash and was curious to see if it could be made to work on the GWH kit as it was originally designed for the Revell kit. The resin is wonderfully detailed and as I got to about half way thru carefully cutting off and cleaning up each actuating rod I did wonder to myself if just using the kit plastic part was actually that bad a choice :) Of course I pushed on as often doing the grinding work like this is all part of the hobby
My patience and work was of course rewarded once I put the nozzles together and matched them up to the rear fuselage. The interior of most modern NATO jet engines is made from a heat resistant ceramic material and is white in color (much like the tiles on the Space Shuttle). The interior of the engines have been painted with de-canted Tamiya White Primer. I started using this paint whenever I need a white that covers really well is is bullet proof. It only comes in rattle cans (which I hate using) so I de-cant it into a small bottle for use in my airbrush. The nozzles become heat stained quite quickly in use and I have applied a coat of AK Interactive Burnt Jet Engine pigment and AK Exhaust Wash.
To make my life easier later on down the track when I need to glue the exhausts into the fuselage and ensure they are aligned perfectly I have added a series of small tabs which are offset by 1mm from the rear edge of the fuselage. These give the resin parts something positive to align onto.
A quick side by side comparison of the Aires nozzle with the kit nozzle. Other than the obvious difference in the actuating rods you will notice that the two are subtlety different in length and shape. I am not sure which one is technically the more accurate but I'm going to assume it's the resin ones.
Turning now to the bottom of the rear fuselage a quick check against photos of JASDF F-15DJs reveals the need to remove some vents and to add some others. The JFS (Jet Fuel Starter) exhaust vent is accurate but GWH just have it as a shallow indent and so I quickly drilled it out and mounted some plastic tube on the interior to give the impression of depth.
The U shaped cut-out on the rear fuselage petals was traced using a scribing template and the cut out by hand with sharp knife and file. The other vents were filled with plastic card and super glue. 
GWH have a deserved reputation for delivering in their kits some of the finest injection moulded parts I have ever seem (the missile fins in this kit are amazing). So it was a major surprise when I started to work on the control surfaces and noticed that the trailing edges of the flaps, ailerons and horizontal tail were so thick. I mean we know that GWH can make beautifully fine parts so it’s not like it is the best they could do. Having said that the solution for the flaps and ailerons was pretty easy (the horizontal tail not so much) but I was just surprised that this was necessary.
You may decide that the trailing edge problem is not worth worrying about and I'm hoping that this photo comparison of before and after will convince you to spend the 10 minutes of sanding and filing to make it right.
So the flaps and ailerons were one thing, but when I picked up the horizontal tail I looked at not only the trailing edge but the front and side thickness. No matter from which angle I looked at it from it simply looked bloated. Once more I consulted the 'Modern Eagle Guide' and Verlinden Lock On and my gut feel was confirmed. Digging once again into my Hasegawa F-15 kit I pulled out the tails for a comparison. This kind of put the final nail in the coffin for the GWH horizontal tails as I realized the amount of effort needed to thin them down to a realistic size was not warranted when I had a perfectly good set of Hasegawa parts in my hands already.
In addition to the thickness issue described above the GWH tails have surface detail that would also need to be removed for a F-15B/D. The raised ribbing on the surface is meant to represent a sealant strip between the gridlock panels. This sealant strip was only present on the F-15E Strike Eagle (as the tail on the F-15E is not the same honeycomb material used on the earlier Eagles). I was happy to remove these and re-scribe panel lines but this and the thickness issue with the whole part made my decision to just swap to the Hasegawa parts that much easier.
As a rule I do not get too carried away with intake trunking. If the kit provides it then that’s great if not then I can normally live with it (I know that some modelers can't and that's ok). GWH do provide intake trunking and even with a torch (yes I tried it) I could not see more than about two inches down the sides. So when I glued them together I sanded the seams as far as I could and applied some Tamiya Basic putty.
The undercarriage parts in the kit are generally very nice. A quick cross reference to some photos showed the support struts had lightening holes drilled out (whereas the kit did not have them drilled through) This was a super-fast enhancement. I did also notice that the main strut on the real aircraft is actually a circular tube all the way along its length unlike the kit part which is very chunky at the top end. I figured that a) this would not be visible on the finished model and b) added to the strength of the gear mounting point to the wheel well. As a result I left the strut as is.
Skip forward to the point where I have now glued the main fuselage top and bottom together. As normal I used some modeling clamps to hold the parts in place as the glue dried. After some seam cleanup I decided to dry fit the intakes and nearly fell off my chair when I saw the size of the gap between the fuselage and intake on the right side (the left side had a gap but not as bad as this one). Now I am not going to blame GWH outright for this as I have since checked several other online builds of this kit and no-one else has had this issue (or if they did the have not mentioned it, which seems unlikely). My best guess is that when I clamped the two fuselage halves I applied too much pressure and they dried in an overly compressed position. Whatever the reason I now owned the problem and had to fix or work around it. If you are planning on building this kit then just heed my words here and check the intake fit as the glue dries on your fuselage matchup.
So how to solve this issue? My first instinct was to reduce the height of the intake part, but given the internal ramps and general detailing inside the intake that would have been a LOT of work. So if I can't shorten the intake to come down the fuselage can I lengthen the fuselage height to come up and meet the intake. Well yes, I could but it would involve cutting open the fuselage and inserting some packing material. So with PE razor saw in hand I carefully cut along the seam (whose glue was not full cured luckily).
With the two parts separated I was now able to use trial and error to determine the right size of packing needed to build up the height. In the end about 25 thou was needed to mostly close up the gap.
The self-inflicted gap was now filled completely with suitably sized card stock and glued in place. I also added some packing around the front end so I could accurately re-create the sharp tip.
And so after a few hours of creative problem solving we are back on track. If you read this article at some point and like me you have this same issue then please email me so at least I know I'm not going mad!! 
By contrast to the forward fuselage dramas, the rear fuselage was joy to work on. I'd advise you to ignore the GWH build sequence and leave the PE parts for the formation lights off until you have glued and sanded the fuselage halves. I also had a chuckle at the GWH instructions that showed how to measure the location for the PE parts. The instructions call for you to locate the PE part at 4.23mm above the centerline. Seriously GWH - 4.23mm ... I'm all for accuracy but I'd like to know how you expect a modeler to measure out 4.23mm. For my model 4.00mm did the job just fine :) 
The next few steps in the build are not about correcting an error but an example of how you can find ways to enhance your build with some creative thinking. The F-15 has very distinctive red formation lights on each wing. These are located close to the wing root on the leading edge. GWH provide these as a panel outline which the modeler can paint appropriately. I wanted to take another approach.
On the real aircraft these lights are tinted glass and I find that using paint (even clear red paint) on plastic parts is not all that convincing. What we need is some clear plastic that is tinted red. As luck would have it you can pickup at your local supermarket cheap plastic toothbrushes that have handles made of tinted red, blue and green plastic. I took to one of these toothbrushes with my razor saw and cut off a chunk. This was shaped to match the cutout in the wing and super glued in place.
Using a sanding stick and file I carefully (and slowly) shaped the plastic part to match the wing leading edge. Once the shape was correct I used micromesh polishing pads to successively polish the clear part back to a shine. Finally the panel lines and rivets were restored. The same technique was used on the wingtip navigation lights.
A final test fit of the radome and radar antenna assembly reveals no problems. Detail painting has commenced on the avioincs bays using Vallejo acrylics. I find these paints are the most versatile for brush painting but they do need to be applied over a base/primer coat or they do not adhere well to plastic.
After painting is complete a light wash of Raw Umber has been applied to tone down the brightness of the base paint. Darker washes also help to highlight the small details and add depth to the parts.
Turning my attention to the next to the external stores, the first cab off the rank is the drop tanks. The tanks provided in the GWH kit do match photos of current F-15's which have simple raised weld lines. This photo of an actual JASDF F-15 (in fact it is the exact aircraft I am modelling) shows a different construction for the tank to that provided by GWH.
As I had the Hasegawa F-15 kit on hand I pulled out the tanks and compared them to the GWH parts. The Hasegawa tanks appear to be a better match to the JASDF tanks and so I will use these on my model.
As I am modeling an aggressor aircraft the only stores carried will be an inert AAM-3 on the left pylon and an ACMI pod on the right. The centerline often carries a ECM pod and I will be using one on this model as well. None of these items come in the GWH kit and so have been sourced from various Hasegawa weapons sets. The missile rails used by the JASDF are the older LAU-114 as it seems they have not yet upgraded to the newer LAU-128 (to allow use of the AIM-120 AAMRAM) like the USAF. The GWH kit does provide LAU-114 rails but these seem to be a bit long when compared to the Hasegawa parts and the correct adapter needed to connect to the pylon is not provided in the kit. I therefore decided to use the rails and adapters from the Hasegawa kit. At this point you may think I am using a lot of parts from the Hasegawa kit. Given that I am building a JASDF aircraft and the GWH kit is designed for an Israeli or USAF bird it’s not all that surprising I should "borrow" so much.
The interior framing of the canopy has been masked and painted black. The bottom framing part has also now been glued to the clear part. As I intend to apply several photo-etch canopy locking hooks to the bottom surface of the canopy frame I needed to putty up the fairly nasty gaps present after gluing. To minimize the chance of the putty fouling the clear parts I have used Milliput which is totally safe around clear plastic and cleans up with water. The PE hooks I plan to use are not included in the GWH kit and come from an old Reheat after-market set.
Not that long ago I came across some great scale lenses in various sizes from a local Australian hobby supplier, Red Roo Models. I have used MV Lenses before (as designed for railway models) but have never come across a stockist of these here in Australia. To more realistically depict the lens of the two nose gear landing lights I will use a 3mm & 4mm lens and simply glue it to the front surface of each light body after painting them.
It was now time to mate the front and rear fuselage sub-assemblies. The fit was pretty good but I was not happy with pretty good and so chose to fill the join with super glue and re-scribe it
With the fuselage join squared away it was time to attach those pesky intakes. With the work I had done previously to eliminate the major gaps all that remained was to glue the intakes on and then use super glue to fill the small gaps and sand everything square. Part B7, the forward fuselage hump is a good fit requiring no filler and minimal clean up.
Despite what the GWH instructions say, the fwd main gear doors and the fwd nose gear door need to be glued in the closed position even with the undercarriage down. The only time the doors are down is when the gear is being retracted or the maintenance crew manually drop them. As the pylons are painted the same color as the airframe it makes sense to attach them now.
The last step in preparation for painting is to attach the vertical tails. I have offset the rudders by a small amount as I think this gives a little more interest and realism.
And so construction is now 99% complete its time to fire up the airbrush. My third and final build update will cover the painting, decaling and weathering. Stay tuned.

Thanks to Great Wall Hobbies for sending this kit to us to build for you