Pseudo Build Thread - BOOH v2.0

[jgibson1@emich]

So this is my first post on the second generation of TRF. I have been slow at building anything rocket related over the past year and meant to do a build thread for my 5.5 inch modded LOC Mini-Mag. Well that build was over a year ago now and I have finally gotten to yet another rocket. This time it is a rebuild of an ill-fated rocket named Bat Out of Hell (aka- BOOH). This was my first rocket built with the intent of going Mach 1+. The rocket is based on a LOC Vulcanite H76 with only a few modifications.

Attached are a couple of images of BOOH. The paint is a custom color mixed in the lab where I used to work. It is a tri-coat with a “special” gold flake/mica midcoat over a red/orange basecoat. The clear was a premium 2k urethane.

BOOH’s maiden and final flight was on a AT J350-W. This flight was supposed to be the shake down flight before it flew on a J570-W. The up part went off with no problems. In fact it was perfectly straight up and disappeared from sight. The silver paint glinted at apogee and a brief flash was visible. That was the last visual confirmation of the rocket. A little while later we heard a horrendous boom as the rocket deployed the main chute after a ballistic descent from 7k feet. No one saw exactly were the rocket landed but the chute was shredded and a rocket couldn’t be found anywhere. I ended up finding the remains one month later. Only a few parts were salvageable including the motor casing.

Here is a link to the up part of the rockets flight.
https://www.youtube.com/watch?v=9bbk823E6pk

 

[jgibson1@emich]

So now I am on to BOOH v2.0. This build will be essentially the same as the BOOH v1.0 but with a few minor changes. The first two biggest changes are that the drouge compartment and the payload bay for the main chute have been lengthened to provide more space for stuff. The third and final change was to place the all-thread off-center in the electronics bay. On BOOH v1.0 I centered the all thread and the 9v battery on the sled was a very tight fit in the compartment. The off-set threaded rod should free up the space available a bit and make sliding the altimeter in and out a bit easier.

Instead of using fiberglass cloth to reinforce the airframe I opted to utilize the strength of phenolic tubing. Using full length phenolic tubing I cut the tube to appropriate lengths and epoxied them into the airframe. Everything fits together like a glove and yeilded an airframe that is incredibly strong and hopfully capable of going mach and beyond. Infact if BOOH v2.0's flight on the J570 goes well I am going to rebuild the motor section as a minimum diameter 54mm design and put it up on an AT K270-W. This should hit about 16-17k feet and mach 2.1'ish. This will definately not happen until next year. So do not hold your breath.

In the photo are the various lengths of tubing used to assemble the airframe.

 

[jgibson1@emich]

I have actually gotten the paint shot for BOOH v2.0 but I will not skip ahead quite yet. After getting the phenolic tubing and fins in place and letting the epoxy cure I set off on reinforcing the fins. I happen to have easy access to Kevlar cloth and this was the fabric of choice to provide structural reinforcement for the fins. After finishing the TTT with Kevlar I moved on to applying the fillets. I used cellulosic thickener dispersed in epoxy to make a nice thick filleting material. Using a piece of PVC pipe and isopropanol , the fillets were shaped and allowed to cure. The care I took during the application and shaping of the fillets resulted in very little time having to be spent sanding, filling, and preparing the fin can for paint.

This is where I will leave it for know but just know that the rocket is far closer to completion than I have described and should get around to posting photos and information to catch up by weeks end.

There are 4 photos attached. The first image shows the fins and aft end of hte rocket just after installing the internal reinforcing. THe second image shows my messy work table/bench in my apartment! Oh, and it shows the Kevlar sheet cut to size prior to application. The third and fourth show the cured TTT Kevlar before and after trimming.