Scaffolding surrounds Little Joe 1A prior to launch at Wallops Island, Va
2010 Update
The build of the "Little Joe" model shown on this website was completed in 2006, and plans called for the model to fly at the FAI World Spacemodeling Champinships held at the Baikonur Cosmodrome that September. Unfortunately, the motors required to fly the model were help up at by the the US Team's contracted cargo carrier in the weeks leading up to the event, and the model did not fly there. The Little Joe did fly, however, at a World Cup event held in Lleida (Catalonia), Spain, in 2008. Check out this short video featuring that flight and the further adventures of the US Spacemodeling Team in Spain!
Final Assembly and Integration
With basic assembly and painting done, we'll begin pulling the various elements of the model together as we get it ready to fly in Kazakhstan. The end is in sight, but there's still a great deal of work to be done at this point, such as staging electronics, rail guides, recovery systems, launch support gear, the data pack, and of course the all-important shipping container.
Electronics
Although a PerfectFlite miniTimer has been purchased for this project, a decision has been made to use an older microTimer instead. Amazingly, the miniTimer lacks the ability to input a specific staging delay time, directing the user to hold down a programming button for the time needed! That's just not specific enough for my taste, so I dug out a pair of older microTimer units to use, which will be set to ignite the capsule motor two seconds following lift-off of the model. The microTimer units on hand were supplied as bare boards, so I'll need to solder all of the power, arming, trigger, and igniter leads into place. As I'm not very adept with a soldering iron the Mayhem Factor will be high for this step.
I used a microTimer unit to develop my 2002 Bumper WAC models for the 2002 Championships in the Czech Republic, testing it over the course of over twenty test flights. Naturally, the unit failed to work when I arrived in Prague, so I had to revert to traditional staging methods (I suspect that I damaged the unit by shorting out the igniter leads while the unit was under power) . I'll take along a spare unit this time...
Happiness is a Warm (Soldering) Gun
Despite a bad track record with a soldering iron, I managed to attach all of the needed wires without burning myself or torching anything. The four sets of wires protruding from the tiny circuit board at center are (clockwise from top) the igniter leads, the breakwire harness, the 9V power connector, and the arming switch leads. The breakwire harness will travel down the rocket to the aft compartment through the mystery tube placed into the motor mount, and a simple switch will be soldered to the arming switch leads.
Aft Compartment Details
Several small sections of square styrene stock were cut and attached to attachment plates to simulate the fin mounting blocks. After airbrushing the blocks with gunmetal acrylic the blocks were mounted in place between the fins and airframe tube. Next, the heat shield and cruciform "spider" were bolted into place. We'll need to paint the allen-head bolt so that it isn't quite as conspicuous.
One of the last details yet to be completed are the nozzles for the Recruit and Sergeant/Castor/Pollux motors. We begin with the Recruit nozzle, which is a repurposed escape nozzle sliced down to size and attached to a short section of styrene tube. After pulling a mold from the finished master, four finished parts are made using PolyTek resin. The Recruit nozzles were molded by pouring a small amount of resin into the mold, then rolling the mold until the resin begins to set. The nozzle walls of the resulting parts are very thin, and very realistic in appearance. We'll hit them with some gunmetal acrylic though the airbrush and attach them to the spider assembly.
We've also created a number of Sergeant/Castor/Pollux nozzles, but I'm not entirely satisfied with the results. I'll wait until after they're painted to make a final call.
My disgust with the vacuformed Sergeant/Castor/Pollux nozzles exploded into full bloom, causing me to create a new master for resin molded parts. At right we can see a finished nozzle with another curing in the mold. The new resin nozzles are MUCH nicer than the vacuform parts.
The Recruit nozzles have been airbrushed with a base of aluminum acrylic, and a small stripe has been masked onto each part. Next, all of the nozzles are attached to scrap plastic and airbrushed with gunmetal acrylic. With the spider removed, the fit of the painted S/C/P nozzle parts are checked on the motor tubes.
The recruit nozzles are attached to the spider, and all of the aft compartment components are checked for fit. The center attachment bolt will require a bit of black paint to help it disappear into the other components. The rivet detail on the fin surfaces is clearly visible on the right photo
Launch Rail Lugs
Now comes the most traumatic step in the project: the addition of launch lugs. After a half-year of painstakingly crafting an accurate replica of the Little Joe, we hack into it to attach a pair of tumor-like lugs, a sin not unlike painting a mustache on the Mona Lisa. The 2008 version of this model will probably have an internal launch lug to save the model from this horror...
At last, the finished model...
After years of research, a string of earlier models, and six months of intensive construction, the Little Joe 1A model is finally finished! With any luck at all, the model will fly on September 27, the final day of competition of the 16th World Spacemodeling Championships at the Baikonur Cosmodrome.
Back to part 1: Capsule assembly...
Back to part 2: Escape Tower assembly...
Back to part 3: Transition Shroud assembly...
Back to part 4: Boilerplate assembly...
Back to part 5: Fin assembly...
Back to part 6: Airframe assembly...
Back to part 7: Paint and Markings...