Above Tannor has our Estes and Cosmodrome Black Brandt II's. The Cosmodrome was a gift from my wife for Father's day 2004 as I've always wanted one.
There was some thought of modifying this kit from a 29mm motor mount to either a 38 or 54 but the idea was dropped with the decision to make this mod later to a different kit that has plastic nose and tail cones. These Cosmodrome kits are just too much of a work of art to start messing with the parts and the nose cone would have needed some major weight modifications, so this mod will be done later.
The first order of business was too build the motor mount, which consisted of one 29mm motor tube and two plywood centering rings. The motor tube was heavily sanded and then the centering rings were epoxied into place with 30min epoxy with milled fiberglass added for strength.
This kit had a different form of motor retention, shown above. Usually I use blind t nuts in the rear centering ring but this wouldn't have been possible with the balsa boat tail so I went with the stock approach which consisted of a piece of allthread epoxied to the motor tube, then a nut and washer is attached to the end and cinched down against the motor case for retention. Motor mount with allthread attached shown above.
The next step was to cut fin slots into the body tube for the fins, shown above.
Next the fins were airfoiled, when done per the directions and to scale this consists of three different angles into the sides of the fins. I deviated slightly and only put two of the angles in, the front and rear angles in the fin were sanded in with a belt sander and by hand with a sanding block to obtain the shape above.
This is the only modification that I made with the kit. The body tube per the kit instructions is one piece, the nosecone is made purely of balsa with this kit and was very light, not much weight for pulling the laundry out at deployment, that on top of the fact that I wanted to be able to have the option of installing an altimeter at a later date and I cut the tube. It was carefully measured and then cut so as to have the cut blend into the paint scheme when finished.
Next the motor mount was installed as well as the balsa boat tail. Then the fins were tacked on. All construction on this kit was done with 30min epoxy with milled fiberglass.
Here all the fins are tacked on, and you can clearly see the two parts of the rocket now.
Next the launch lugs were attached, then fillets were applied to the fins, again with 30 min epoxy/milled fiberglass.
While these dried I built and later installed a coupler and bulkhead assembly to the upper body tube assembly.
After all the fillets were applied to all three fins and to the launch lugs I then applied fillets to the launch lugs and drilled pressure relief holes and then readied for paint.
Stock colors were painted to scale using the painting guides supplied with the kit. When you compare this kit to the Estes kit you'll see some differences, the larger Cosmodrome kit is the correct paint pattern.
Built 7-10-04
Diameter 2.6" Length 50.8" Weight 23 oz, 29mm motor mount and parachute recovery. 18"
***Update Maiden Flight***
Maiden flight was made on 7-24-04 with TSM, see launch page for details, maiden liftoff picture below
Maiden flight made on an AT G64
After it's maiden flight this is what I had upon recovery, the ejection timing looked about right but it appears the nosecone came back and hit the fins, which then took a chunck out of the soft balsa, the fin sufferred a very minor ding that can be covered up with a little paint.
Repaired 11-29-05
Super Fil is a pretty amazing product. I've been meaning to buy another nosecone or have one made, but finally it struck me I may be able to make something else work, and tried to fill in the huge chuck with some Super Fil.
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The first thing I did was mix up a batch and then fill in the hole liberally.
After the Super Fil had fully dried I then used a dremel and some 100 grit paper to roughly sand the area.
After I got it close I then proceeded to sand by hand with 150 grit and then 220 grit until I had it completed and back into the original shape.
Not the best picture but after a few coats of paint it really is back to new looking, with no noticeable dimples or dents in the cone, actually a very good job for me, so this rocket is back to good as new and ready to fly next flying season.
After repairs flight 2 on an AT G64, April 2006.
