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I've been slowly working on the new Revell SR-71 kit. Not because it is a bad kit, just because I am trying to take my time to ensure I don't mess it up given how expensive the kit is. Plus I am trying some things with it that are a little different from standard "out of the box" faire in order to help give some hints to you guys to help potentially improve your building experience.




Rather than starting with the fuselage, I decided to start with the engine nacelles. The Squadron SR-71 Walk-Around book by James Goodall provides some nice references for the engine internals. Overall while the assemblies are a little simplified, I think Revell did a good job here. You get full intake trunking, but I wouldn't worry about going too crazy on the details here since once the inlet cones are in place, you can't see much inside anyway.




Pictured is the left engine inlet and cone. Revell's instructions are to build the three piece cones first, then build the four piece inlets around them. It seems like a complicated assembly but it isn't. A couple part numbers for the inlet cones are transposed in the instructions, but they only fit together a certain way. Parts numbers are molded onto these parts so it is pretty easy to figure out what goes where even after the parts are clipped from the trees. Before intake assembly, I primered the assembled cones and unassembled intakes in Mr Surfacer black primer. That's all you really need even though the instructions recommend a metallic color instead.




Even though the instructions don't mention it, I found out if one is careful, it is possible to assemble the intakes in such a way as to keep the inlet cones unglued. This allows the cones to be slipped in and out of the intakes and with some modification you could probably even position the cones further back if you wanted to represent a Blackbird at supersonic cruise. To do this, build the intakes around the cone and hold the assembly together with masking tape (Tamiya in my case) to act as a form of a jig. Once everything is positioned properly, Carefully pull back some of the pieces of tape and use your glue of choice to cement everything into place a little at a time. I use plastic weld glues for strength. So I glued the back, then the front, and after a little wait I cemented the center areas. If done properly, you should be able to cleanly slide the cone assemblies out the front of the intakes. It is also a good idea to mark which cone is which and what the top section is so you can at least align the parts properly. After sliding the cones out a few time you get a pretty good feel for how they should fit because when you pull the cones out once everything is sealed inside the nacelle, you will need to be able to slide the cones in the blind.




Once the intakes are assembled, you can glue the bulkhead pieces on at the rear. Then you can drop the assembly into the bottom outer wing/nacelle half. It isn't a bad idea to spray in a little more black primer into the outer wing/nacelle pieces. Once the engine pods are fully assembled, you can now take care of the glue seams at the front of each intake without the cones getting in your way. I wouldn't worry about going too deep in with your seam cleanup because I said before, you can't see too far back anyway. But, making an effort to clean up the fronts will result in a better looking model. When everything is to your liking, the cones can be slid in with little effort and they align in their slots just fine.


Trivia: Those oval protrusions on the insides of the intakes are called "mice". Kelly Johnson added those to help restrict the air flow. They didn't know exactly how much airflow would be needed for supersonic cruise, so the intake was purposefully designed a little too large and the mice were used to restrict and tweak the airflow down. It was done this way because if the intakes were too small to begin with, it is a lot harder to correct that problem than it is to help restrict too much airflow. 

Edited by Jay Chladek
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Next I moved to the engine exhausts. The flame holder area of the J58 engines is rather large and hollow, plus it takes up about a third of the length of the engine itself. To help simplify construction of this area and help prevent an exposed seam that would need to be dealt with on the inside, Revell molded the flame buckets as one piece tubes with a slight taper to them which gives them a forced perspective. The rings of the flame holders are molded as a separate piece which glues on at the front. The exhaust nozzle at the rear is also molded separately. You get four of these assemblies in the Revell of Germany kit since they also are used in the exposed J58 engines intended for the display stand. The Revell USA kit will only have two.




I spent a lot of time at the SAC museum looking at the J58 engine from 61-7964 which we have on display and I wanted to try and duplicate the colorings inside the flame buckets properly.




To start with, I airbrushed the insides of the flame buckets and flame holders with Tamiya LP-35 Insignia White. Any brand of off white can work. Then I gloss coated them in preparation for wash application. On the flame holder rings, I used Tamiya black enamel wash to represent the deep recesses. In a couple spots I had to touch up areas with a black pen though. For the flame bucket housing, I mixed up a diluted mixture of Tamiya smoke tint wash to get the slight staining I was after. 


For the nozzle section, I painted those parts in LP-35 for the raised petals, and Tamiya gray metallic for the recessed parts and the outside. Then to give everything a little wear and tear, I gave the insides of the nozzle a Tamiya brown enamel wash to represent the slightly brown soot discoloration. The results may not be exact, but I was happy with my efforts.




You can see a little discoloration of these nozzle petals, although when they were pulled out of the jet after its flight in 1990, they were a bit darker and browner. So I believe World Wide Aircraft Recovery cleaned them up a little before the engine was put on display at the museum. 




This picture of a picture displayed on a wall at the museum shows an engine being dismounted before the aircraft was trucked over the road 30 miles from Bellevue to Ashland on its landing gear. You can see how discolored the nozzle area itself looks while the flame bucket looks a lot brighter in color.

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On 1/25/2022 at 2:29 PM, Jay Chladek said:

Trivia: Those oval protrusions on the insides of the intakes are called "mice". Kelly Johnson added those to help restrict the air flow. 


Thanks for that trivia.  As to their purpose I suspected as much but did not realize they were a "tuning" aid.  The equipment I work on features a "dual displacement" pump where the volume delivered changes over the stroke of the piston,  these would do essentially the same as the max diameter of the shock cone nears the mice.

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Work continues. Originally in my review I didn't believe that Revell had represented the "pinch in" areas around the aft bypass doors properly on the kit. Here it is as visible on the SAC Museum jet:




And here it is on the bottom of the nacelles:




But as it turns out, Revell did make an attempt to represent these pinch in areas as there is a bit of a profile change on the nacelles. Unfortunately, due to how Revell represented the open doors, they do need some work to improve them since the dividers between the doors don't extend all the way into the part with the doors and there is no scribe marks representing the hinge points of the doors.

There are two ways this can be fixed as I see it. One way is to scribe in the door hinge points all the way around the part. That can be done relatively easily, but I also noticed on my test fits that there is a bit of a step between the tapered section of these parts and the full diameter of the engine nacelles themselves. To fill and cleanly sand that is a bit trickier to do IMHO. So I came up with a slicker fix for both problems.


My solution involved the use of Evergreen #113 Styrene strip, which measures .015 x .060 (0.38 x 1.5 mms). I glued the strips (with plastic weld) to the fronts of the divider door area starting at the dividers themselves and going to the part edge. You can see the comparison in the following photo. The unmodified assembly is on the left, the corrected part with the styrene strip added is on the right.




The strips overhang the lip of the part a slight bit, so I recommend sanding them flush with the part once the glue is dry. You might be able to do this with .010 thick styrene, but I went with the .015 to give me a little cushion as sometimes plastic weld glues can distort styrene that is too thin. Once the strips were completely dried and cured, I helped reduce their thickness a little and helped to blend the contours on the sides. Test fitting these assemblies with the rest of the nacelles shows the modification works very well IMHO and it only took about 20 minutes per assembly:






You can see on top of the nacelle that there is a flat raised bit for a tail piece to attach relative to the pinch in areas around the doors. This raised spot is represented on the bypass door assemblies as well but there is a step there. So once I get the nacelles firmly glued together I will add another shim of strip styrene to help blend the contour rather than trying to fill and sand that some other way. One additional benefit I found is looking at the actual jet, there looks to be a thin strip of metal right ahead of the doors. In the following image I have adjusted the contrast to help make this detail more visible.




The strip added to the bottom by comparison blends into the contour more cleanly, although there is an attachment hinge/bracket that could be scribed in a little better (half of it is represented on the kit parts).




In any event, it is a relatively easy modification to do and helps reduce the workload as far as seam cleanup goes. BTW, as I understand it these bypass door pieces seem to be prone to sink mark problems. Apparently not all kits have the sink mark issue, at least not to an extreme level. One of my parts had more sink marks than the other and I just filled them with gap filling CA glue and sanded the areas flush. To separate these parts from their trees, I left a bit of material on the parts with my sprue cutters and cut the nubs closer to flush with my razor saw before sanding them down. That way I avoided any excess plastic gouged out of the parts. 

Don't worry about filling the marks on the insides of these parts since they are going to be covered up by the engine exhaust burn buckets anyway. I highly recommend painting the insides in black though before gluing these parts in place on the backs of the nacelles.




Next step will be to glue the nacelles together and sealing everything in. Once again, I like what I see and this is coming along better than a Testors kit IMHO.

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  • 2 weeks later...

Work continues to progress, albeit slowly. Not due to any fault in the kit, just my speed is all as I want to get this done right. In any event I have the engine nacelles built and primered.




Before adding the exhausts to the nacelles, I gave them a shot of black primer outside in case they were visible inside the open bypass doors.




I also did the same with the insides of the bypass door rings to make sure no bare plastic would be visible inside the back end either. Before installation I did shoot the outside with black primer to make sure my filling and sanding of the doors was done properly because they had a lot of sink marks. Not all kits have the sink mark problem, but it can happen so it is best to be prepared for it.




When done this is what I had. The strip styrene I used filled the transition area from the doors to the nacelle body nicely from top to bottom. The black lines on top are guide marks to help me know where the panel lines are when I fill and sand. The fit of the three pieces that make up the nacelle bodies and outer wings are pretty good, but there are steps up top that require a bit of work to address. Next time I build one, I may sand the insides of the interlocking tabs to help the parts fit more flush on the outside.




The insides of the exhaust channels and the nozzles were painted and the nozzles have been temporarily tacked on. I used a combination of Tamiya Gunmetal (for the forward part of the channels) and Light Gunmetal for the nozzle petals. Looking up the exhausts, they seem to look the part nicely.




Here you can see the intakes with the spike cones pulled. By building up the intakes the way I did and not gluing the spikes in, I can address the seams on the intake lip. I know, one could paint a lighter shade of metallic in these areas as the instructions suggest, but just go straight black as trust me, you won't be able to see much in there anyway. I gave the intake throats some more black Mr. Surfacer and sanded them down in spots to disguise any serious seams which "might" be visible when the spikes are installed.




And here are the mostly complete nacelles after a going over with Mr Black Surfacer 1500. No they are not done. But what better primer and scratch filler to use than a black one for a black jet. I'm going to work on the fuselage for awhile before finishing these up in preparation for the final assembly. BTW, when you do your paint work, it is not a bad idea to stick in a tube or some paper rolled into a tube into each exhaust to help prevent any black overspray from getting in through the bypass doors and possibly screwing up the paint work on the inside.

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Great work on this build, Jay! I'd really want to have one of these new Revell kits right away, but I'm holding back until @JeffreyK releases his. (Still there's the old Italeri 1/48 kit somewhere in my husband's stash + lots of the many, many aftermarket sets there are for it).

Apropos of this picture here: 




Perhaps the exhaust ring petals could be thinned down a bit. What's your pick, Jay? 😂








Edited by Gwen Phoenix
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  • 5 months later...

It has been awhile. The Blackbird has been "done" since IPMS Nationals, although I may do some tweaks to it. I did shoot some in progress pics though for a few steps, so here is the next update. Let's start with the cockpit:




I modified the aft instrument panel slightly to move the MFD box further back into the cockpit. It took some precision work, but I was happy with the results. I applied the stock decals to both the front and rear panels and they worked as advertised, going on with minimum fuss and snuggling down with an application of Micro Sol. Because of my parts modification, I had to carefully cut the aft panel decal into multiple pieces for the instruments, the MFD, and the two control boxes that surround it. But again they went on with no fuss and minimal distortion. Once they were dry I sprayed the panels with clear and gave them a black pin wash to pop out the features, such as the map and checklist holders in the aft pit. I also used some colored pencils to pick out some of the yellow and red handles a bit better.




Here's the front cockpit all done pretty much except for the seat and the control stick. I scratchbuilt a throttle quadrant. I have seen the 3D color printed panels done by a few companies and honestly, with the right amount of painting I think the stock cockpits work just fine. Now if the aftermarket companies REALLY want to make their 3D cockpits become a necessary item, they need to also do the circuit breaker panels that sit behind the panels in both the front and rear pits. The breakers are a necessary part of Blackbird operations and the flight crews have to know them by feel since they can't look down in their pressure helmets. They pretty much learn to operate them by feel in order to diagnose and troubleshoot problems at Mach 3.




And here we have the aft pit. You can see the work I did on the rear MFD a little better. Again, some breaker panels for the aft cockpit would be most helpful for this kit and would really add something to it.



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Now we move to the nose. The Revell kit includes options to do the jet with a CAPRE nose or an ASARS one. They give you two nose tops, but only a common CAPRE nose bottom. Using a diagram I found in the Jim Goodall Aerofax book, I opted to modify the nose bottom to give my model a proper ASARS nose. It was used from about 1984 onwards and has a distinct shape difference on top from the earlier style noses. Since I was representing 979 at the end of its operational life, it likely carried the nose on at least some missions. To date, only the jet on display at Duxford in the UK has an ASARS nose.




To act as my scribing guides, I started with Tamiya yellow tape to define the straight lines, then covered it with the white flexible Tamiya tape. After nose assembly I applied a wash of Tamiya black to the raw plastic to help pick out the panel lines more easily so I could apply the taped scribing guides. My scribing started with a number 11 blade back edge, then I switched to a Flexi-File brand slot knife. Before using it, scribing was a bit of an art I couldn't quite master. But using the tape in combination with it, I managed to pull off some very clean scribe lines that needed almost know cleanup from mistakes.




This is the top nose, also with a panel like wash applied to pick out details. I used it to give me a good idea where to apply the tape on the bottom.




And here is the nose bottom after scribing. Once I was done with the passes, I used some Mr. Dissolved Putty, then some primer to fill the original CAPRE nose lines that weren't present on the ASARS nose. 




Here you can see the nose bottom again from a more straight on angle. I did a few best guesses as to where some of the lines went, but consulting the diagram and as many photos as I could, I think I hit the bullseye.



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I discovered an error on the kit during construction of the tails. There is some excess plastic on the bottom of the right inner tail that should not be there. The problem isn't present on the left tail and if left there, you end up with a big gap visible on the right outer tail where it slots into the engine pod. These pictures illustrate the problem.


First we have the left tail:




And then we have the stock right tail (both viewed from the inside)




I have accented the spot with a black wash after scribing in where I needed to scribe in a separation line to remove it. Here is the issue in closeup form.



The fix is very easy to do. In my case, I used white Tamiya tape to act as a scribing guide and then scribed in a line and accented it with a black wash. Then I just continued scribing deeper and deeper until I cut the excess plastic off. The result is the left and right tail root edges both match and they slot into the engine pods perfectly with no unsightly gaps.


Edited by Jay Chladek
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