Model Rocket Building Blog

Estes SR-71 Blackbird Build Part 1, Parts
Oh boy - this should be a fun one! Skill Level 2? No, I don't think so. More like a Skill Level 4. It's interesting to look up the Centuri Blackbird instructions at Jim Z's -   HERE This BT-50 based model looks to be a downsize of the earlier Centuri kit. The larger BT-60 Centuri ...
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Estes SR-71 Blackbird Build Part 2, Fin Prep
These fins had a wide laser cut "wedge" on one side. (Left side) On the right is the second fin sheet flipped over. It took a lot of laser to cut through this "balsa". There was plenty of left over wood on either side of the fins. I cut it off and threw it into the spare parts box. ...
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Estes SR-71 Blackbird Build Part 3, Engine Mount
The green centering rings got a shallow notch for the engine hook. The blue engine block got a "Bradycros" notch for the engine hook. When this notched block is glued in place it won't wobble over the top of the hook bend. Kevlar was added instead of the tri-fold mount. There isn't much room in ...
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Estes SR-71 Blackbird Build Part 4, Plastic Prep
  The inlet/tailcone were cut using a few passes with my hobby knife. I didn't think a razor saw was needed.   The open back end of the tail cone was sanded round with some 220 grit wrapped around a dowel. The edges were thicker near the mold seams. The inlet cones still had ...
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Estes SR-71 Blackbird Build Part 5, Fin Edge Gluing
Gluing together the inner wing pieces was a little like putting together a jigsaw puzzle. The instruction illustrations were not drawn to scale which only made it more confusing . Be sure the front piece of the inner wing is facing the right direction, probably the opposite of how you ...
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Estes SR-71 Blackbird Build Part 6, Inner Wing Gluing
I don't like cutting up instructions to use the fin marking guides. Sometimes when instructions are cut up you remove upcoming steps from the other side of the sheet! I traced the kit fin marking guide onto copy paper but it didn't line up well around the BT-50 tube. I ended up cutting out the ...
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Estes SR-71 Blackbird Build Part 8, Bottom Shroud Forming
Skill Level 2? No way Estes!!!  The instructions have you forming the heavy card stock curves using your fingertips. I don't see how this could be done. I tried! The card stock is thick and under some pressure when pulling in and forming the curved sides. I went back to an old standby of ...
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Estes SR-71 Blackbird Build Part 7, Bottom Shroud Gluing
Here's the bottom shroud sitting on the body tube. Do a LOT of dry fitting on these, if you screw it up the model might go in the trash can. I'm tracing around the cut out box once everything was in position. The front end of the shroud is even with the extended tips of the inner wing. TIP: ...
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Estes SR-71 Blackbird Build Part 9, Bottom Shroud Tabs
This is as even as I could get the bottom shroud against the inner fin. I'll wait to trim the balsa after the top shroud is in place. Here's why you should pre-bend the overlap tabs. They will be under pressure and want to pop up. It's hard to get a good crease right up against the inner ...
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Estes SR-71 Blackbird Build Part 10, Top Shroud Glue and Form
  The upper shroud half is glued on much like the lower half. Start with the center line gluing lining up the tick marks with the lines drawn on the body tube. Check from the rear to see if the upper shroud is straight. Let the glue dry thoroughly before steaming the shroud for shaping. ...
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Estes SR-71 Blackbird Build Part 11, Top Shroud Front Forming
It helps to pre-bend the front of thee upper shroud where it meets the nose cone base lip. The card stock won't set down in the middle without some coaxing. Roll it up and around your finger. Make the bend smooth with no creases. Here I'm holding down the glued front sides with a dowel ...
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Estes SR-71 Blackbird Build Part 12, Shroud Ends Fitting
The front of the top shroud had lifted at the center tick mark. This won't help the fit of the nose cone. The tick mark cut was extended all the way to the front of the shroud. Be careful not to cut into the BT-50 tube underneath. On side off the cut was set underneath the other. Medium ...
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Estes SR-71 Blackbird Build Part 13, Shroud Smoothing
I went ahead and primed the nacelle tubes, nose cones and tail cones. After sanding you can see some primer still left in the molding seam in the nose cones. Steaming the shroud sides gave me a nice, smooth curve to the card stock in the mid areas. The problem is at the top where the glue ...
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Estes SR-71 Blackbird Build Part 14, 24mm Conversion?
If you've ever seen the SR-71 Blackbird fly you know stability is a concern. I've seen them fly perfectly vertical or turn and go horizontal into the wind. Installing a heavier engine in the rear could add problems. Before gluing in the engine mount I thought about converting the SR-71 ...
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Estes SR-71 Blackbird Build Part 15, Shroud Fills
On the front of both shrouds are cut out areas used to line them up down the drawn pencil lines. On the right is the drawing of the bottom shroud with a larger rectangular cut out at the front. I can only assume this is to simulate the landing gear hatch. At the front of the top shroud is a ...
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Estes SR-71 Blackbird Build Part 16, Shroud Fills
The fill piece was rolled over with a dowel to indent a small curve. This will better fit the curve of the shroud. When gluing paper to paper you don't have to use much glue. Apply a thin coat and press the fill piece into the recess. Roll the dowel over the fill piece and shroud molding the ...
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Estes SR-71 Blackbird Build Part 17, Engine and Outer Wing Gluing
In Step 13 the engine assemblies were glued on the outer edge of the wing. I didn't use the wing jigs here. They are supposed to go under the outer wings for support when gluing. I set them under the outer wings for a test but the bottom surface of the wings  were slightly higher than the ...
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Estes SR-71 Blackbird Build Part 18, Primer and Black Paint
  The model got a coat of gray primer filler. There was quite a bit of 400 grit sanding. Florida is finally cold and paint drying time is slow. After the first black coat there was more sanding. There are a LOT of inside angles to sand on this. And the last heavier coat of ...
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Estes SR-71 Blackbird Build Part 19, Decal Comparison, Stick On to Water slide
Daniel (dlazarus6660 on YORF) sent me the water slide decals for the SR-71! On the top are the stick-on decals that were included in my kit bag. You can see the die-cuts in the clear thick material. Below that are the decals Daniel sent! These were from an earlier version of the kit. Water ...
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Estes SR-71 Blackbird Build Part 20, Tips from the Forums
There have been a few suggestions about clustering this one. My concern is how far the outside engines are from the center line. If you don't get all three engines to light at the same time it might pinwheel. I've seen that happen once. Here's some TRF quotes: Verna:   "Whatever you do ...
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Estes SR-71 Blackbird Build Part 21, Decals
Thanks again to dlazarus6660 on YORF for sending me some water slide decals for the Blackbird. The older versions of the kit had the water slide decals. More recent kits have the stickers. I used a marked piece of card stock for placement of the vents on both the opposite engine tubes. I don't ...
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Estes SR-71 Blackbird Build Part 22, Decals
  Here's the Blackbird with all the decals in place. I've yet to glue the inlet cones, tail cones and engine mount in place. After the decals are dry, they'll get a coat of Future. After that the entire model gets a dull coat spray. Normally I don't use dullcoat. Fi ...
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Estes SR-71 Blackbird Build Part 23, Engine Cone and Clear Coat Problems
The inlet cones had a loose fit in the tubes. I added a wrap or two of tape but still left some plastic exposed on either side so the plastic cement would grab. The instructions say to glue them in with 1 1/4" exposed. I did a dry fit first and it seemed like the nose cone stuck out too far ...
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Estes SR-71 Blackbird Finished!
    This build was tough! How Estes could label it as a Level 2 is beyond me. The body shrouds would be impossible for a younger builder. Fitting the shroud front around the complex curves on the nose cone shoulder took too much effort. In the end, the match still isn't ...
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