This summer I decided to support Marc G. and not buy any kits until I had used up some of the stuff I already have. This build fit right into that idea since I had a couple of BT-55 tubes and a left over 24mm MMT from an Executioner that I built with a 29mm MMT. The only thing I needed was a N/C to fit the body tube and some centering rings. Found both of those at Uncle Mikes Rocket shack, so I'm in business.
Green Jello was asking about modifying his CC Express to use E motors, and when I took a look at mine I discovered that most of the fins on the booster had been cracked after just a few launches. I suggested he add recovery to compensate for the heavier E motors and I think he is working in that direction with his build here:
My build went in another direction, I'm trying to beef up the booster so I don't crack fins every time it lands. I started by cutting my fins slightly longer and making them through the wall. I papered the fins and sealed the edges with medium CA. The MMT was modified with "stringers" that filled the gap between the body tube and MMT:
That photo also includes the half moon baffles and bulkhead/anchor for the sustainer. I had a piece of blue tube that fit perfectly inside the BT-55 and that made cutting the slots much easier:
I added a piece of masking tape to protect the blue tube, then managed to score it anyway. No biggie, it will buff out when I need it later.
The tricky part was getting the body tube slots to line up with the stringers when gluing it together. I did pretty good with that and the slight mis-alignment was corrected with an exacto knife. Balsa wood is so easy to work with.
I used Titebond in the slots, let it dry a bit and stuck the fins in with more glue on the root edge. My modified fin guide came in handy for this:
The sustainer was done the same way with stringers and TTW attachment of the papered fins. I also added the baffle pieces using the blue tube to slide them in. I use Elmers glue-all for couplers and baffles, and treated the pieces with 5 min. epoxy to endure the ejection charge. My eye bolt is attached with a wire nut and washer that are epoxied in place. I use kevlar for recovery and the eye-bolts are brazed shut for added strength. Here it is ready for paint:
I really like the N/C I got from Uncle Mikes, just not sure what it is made from. It's not blow molded so it doesn't have the seam, but it has a nice attachment point that runs the length of the cone:
This build took me a bit longer than usual, mainly because I had to figure out the different sizes to fit the "E" motors. Then adding the stringers to the MMT was a little tedious. All in all, I'm quite pleased with the outcome. Now it just needs to survive the new E12 motors.....