Brief:
The BSD Diablo is a short, fat, 3 finned rocket with a wicked look. With its 38mm motor mount, it definitely is designed for HPR. However, with a 29mm adapter this rocket can be flown on some G motors without any problems due to its relatively low weight.

Construction:
The kit has relatively few parts. They include: a 17" LOC style body tube, a 20" nose cone (4" is shoulder), three 3/16" plywood fins, two 1/8 plywood centering rings, one 1/2" paper launch lug, one 8" long 38mm motor mount tube, one 1/4" eye bolt with washers and nut, one 3/16" quick link, one 30" parachute, one 4' long, 1" wide, grommeted nylon strap, one 10' long, 1" wide elastic shock cord, and a motor retention system that consists of two T-nuts, two 6-32 hex head bolts, and two metal clips. I also purchased BSD's 29mm adapter with my kit.

This is a fantastic, easy kit to build. In fact, I had to consciously slow myself down because it is so easy to follow the excellent instructions and assemble the excellent components that I found myself getting too far ahead of where I should have been. All of the components fit together well with only a little sanding of the centering rings. When I received my kit, the body tube was not marked with the fin alignment lines or the launch lug line. However, a quick email to Scott Binder at BSD and the problem was resolved. Scott sent me a new body tube that had been marked and threw in a 4" bulkhead assembly in addition. Now that's great customer service! Having to cut the fin slots yourself is a little tedious but, not a big deal.

I deviated from the instructions in a few ways. First, when building the motor mount, I didn't secure the rear centering ring. I did this because instead of creating internal fillets with epoxy I used 2-part expanding foam to fill the fin can. Second, after epoxying the forward centering ring and motor mount tube in, I dry fitted the fins. With the fins in place, I drew a pencil line on the fins along the outside body tube joint. Thus, when I removed the fins, I had how much of the fin would be inside the body tube. I then drilled a 5/8" hole in the center of the fin root. This hole is to allow the expanding foam to flow through the fin root and lock it into the fin can. I then epoxied the fins to the motor mount. Three 1 ounce applications of 2-part foam filled the fin can. After cleaning/shaping the foam on the rear of the fin can, the rear centering ring was attached with epoxy.

My only complaint about the construction is that the motor retention comes with a separate set of instructions. If you don't read those instructions first, you won't notice the bold warning that you should install the retention hardware before assembly! Luckily, I was able to still attach the hardware after assembly.

Finishing:
Since I was planning on using this rocket for my Tripoli Level 1 certification, I glassed the entire airframe using 2 ounce fiberglass cloth and 30 minute slow-cure epoxy. After glassing, fillets were added to the fin/body joints and along the launch lug using 30 minute epoxy and micro-balloon filler. Some sanding with 80 grit sandpaper and it was ready for some primer. I used Rustoleum gray automotive sandable primer. This primer is nice because it fills a lot of the imperfections. Sand, prime, sand, prime. You know the drill. I also used some Elmer's sandable wood filler putty to fill some of the larger imperfections. Eight coats of primer later, ready for color coat. I chose Rustoleum Safety Red. Two coats of color and then the decals. The decals were definitely the hardest part. The decals are beautiful but, they're long, skinny, and very sticky. A friend of mine suggested that I dip them in water with dishwashing liquid to allow me to slide the decals in place. I was too chicken to try though. The decals turned out OK but it takes a lot of patience. After decals, I shot it with 2 coats of Rustoleum clear enamel.

Construction Rating: 4 out of 5

Flight:
The Diablo's first flight was to be my Level 1 certification flight. I had an H128W lined up for my 29/180 casing. The clips provided with the motor retention kit wouldn't fit with the 29mm adapter so, I had to fashion some new clips out of some flat brass stock. When I arrived at the launch site to pick up my motor, there was no H128 to be found! Thankfully, the vendor had some H165 Redline motors that would do just fine. I used a Top Flight Kevlar® chute protector and shock cord protector instead of wadding. The H165 was prepped with a 10 second delay and placed on a 3/8" launch rod. That Redline will move fast! It boosted straight up to probably just over 2000 feet. It was a beautiful launch.!

Recovery:
I tied loops into both ends of the elastic shock cord and one loop about 1/4 from one end. These loops were used to attach the elastic to the nylon strap, the nose cone, and the parachute using quick links. I also included a swivel to keep the chute shroud lines from tangling. The recovery system worked great. The descent was a bit fast but, that's probably because my rocket is towards the upper end of BSD's expected weight. A bit larger chute could solve this but, I'm happy with the faster descent. The glassing that I did makes it able to withstand a rougher landing and I get less wind drift this way.

Flight Rating: 5 out of 5

Summary:
I love this rocket. The main pro's are it's ease of building, the clear instructions, and the tremendous customer support that you get from BSD. The main con's are the separate instructions for motor retention and the retention system's inability to accommodate the 29mm adapter.

Overall Rating: 5 out of 5