29mm Black Shadow

[Buckaroo]

So I was sitting around moping on Saturday because the Music City Missile Club launch had gotten rained out...

The moping continued into Sunday which also got rained out... :hot:

So I didn't get to launch, and I couldn't even paint because of the humidity. I wasn't in the mood to drag another kit out of my LPR build pile since I've already got 8 finished rockets that haven't flown yet, and another 6 that are built and in the finishing process... :bang:

What to do?

I decided to start my first no kidding mid power build. This rocket is going to be a 1.77x upscale of the Thrustline Black Shadow, using Semroc #225 tubing and a 29mm motor mount. Rocksim gives me a nice range of 1000-2500 feet on E-F-G motors...

Today I cut out the fins using 1/8" Basswood, pretty much a straight upscale with the addition of TTW fin tabs. This rocket is going to be overbuilt, but hopefully it will give me some experience when I start my Level 1 build soon. Happiness Returns...

Last Couple of pics show stock Black Shadow for comparison

 

[DM1975]

Looks like a cool project, and I love the sig line from Buckaroo Banzai.

 

[Buckaroo]

...love the sig line from Buckaroo Banzai.

The most under-appreciated movie in history! John Lithgow should have won an Oscar! :cyclops:

 

[new2hpr]

Penny! Hold my thruster!

 

[Handeman]

That does look like a cool project. You should look forward to a lot of great flights!

My opinion, don't worry about over building it. Unless you are going for the ultimate altitude, overbuilding makes it a lot tougher when it lands hard. The extra weight will also keep the altitude down because when you start pushing 2,000 ft. walks can get quite long. I actually try to keep flights below about 1,500 ft. unless they are dual deploy, it is a really calm day, or a huge field, or a combination of two of these.

 

[Buckaroo]

Got some more parts in the mail today

Just waiting on the recovery components now. I may start cutting the fin slots tonight... or not

 

[Pantherjon]

Looks like a kewl upscale there! I finally got around to painting my Black Shadow the other day..And put some lettering on it..Looking forward to more of your build Matt!

 

[maricopasem]

Great project!

 

[Buckaroo]

OK, after a couple of false starts I finally did some work on this project tonight!

First thing to do was to cut the main body tube down to the proper length. I use a simple guide rail with a stop set-up and hold either an X-acto knife or a razor blade against the tube for a couple of turns until I get a good groove going. I typically finish the cut freehand by just pressing the blade into the groove as a turn the tube under it. Works well for me, although I must say that this was the largest and heaviest tube I had ever cut. It came out nice :clap:

 

[Buckaroo]

The next step was to mark the body tube and cut fin slots. I made my own marking guide by just wrapping a piece of paper around the tube and marking where it overlapped. I then laid it out flat and measured out the fin lines, wrapped it around the tube and marked it up. I use a piece of aluminum angle stock to extend my lines and also as a straight edge when I cut the slots.

I've also been busy cleaning up the fins and shaping the leading/trailing edges.

 

[Buckaroo]

And of course the obligatory "dry-fit" photo op with an original Black Shadow for comparison.

 

[dr wogz]

I think we need to convince John to kit both!

nice build!

 

[Buckaroo]

OK, I haven't been keeping this thread up to date, been building like a fiend trying to get ready for Southern Thunder!

Time to catch up.

First up was the motor mount. I am using Semroc #115 tubing and Semroc plywood centering rings. I also got a 29mm Aero Pack retainer, whihc didn't even come close to fitting, :confused2: and when I tried to force it on, I ended up crushing the end of the tube! I ended up peeling off a pretty good layer of the tube to get the retainer base to fit.

 

[Buckaroo]

Next I measured the position for the fwd centering ring to line up with my fin tab slots. I am using 600# flat woven kevlar for a shock cord. I filed a shallow notch in the fwd cetering ring and epoxied it in place with the kevlar underneath. I knotted the kevlar behind the centering ring and the epoxied the tail to the motor mount tube. Since I am planning on flying single use motors I also added a thrust ring to the end of the tube and gave it a coat of epoxy. The pics show the completed fwd end of the motor mount and also with the aft centering ring and retainer, which will not be glued on unitl after the fins are in place.

 

[Buckaroo]

Don't have any picture of the motor mount install. I ran a bead of epoxy around the inside of the body tube and slid the mount into place, using the aft centering ring to make sure it was aligned. I almost managed to forget to make sure the shock cord tail was BETWEEN the fin tab slots Luckily I caught it before the epoxy set. I used a long dowel to fillet the fwd face of the centering ring.

I cut a fin alignment template out of mat board and proceeded to glue the fins in place. I put the aft centering ring in place to keep the motor tube centered , but after the first two fins were in it wasn't really necessary.

 

[Buckaroo]

Once all the fins were tacked on it was filletin' time!

 

[Buckaroo]

Somewhere along the way I also managed to install and fillet the aft centering ring and a 1/4" launch lug. I had read somewhere about folks that had trouble with cardboard launch lugs swelling in high humidity so I ran a Q-Tip of epoxy through the inside of the lug to seal it up.

No in progress pics for this, only after the fact.

 

[Buckaroo]

I wanted to try something new with the nose cone which I must say is a beautiful balsa upscale of the classic Estes BNC-55AC by Semroc. I decided to use MinWax wood hardener to hopefully toughen the wood up a bit. I gave the wood several coats in quick succesion like the instructions say and was pretty happy at first since the wood seemed to soak it all up. I was dismayed to come back several hours later and find that a lot of the hardener had oozed back out of the wood and dried on the surface in small hard bubbles. I left it sit for several days to cure, and eventually sunded it down without too much trouble. After all that work I gave the balsa the fingernail tap test to see how much tougher the wood was, and managed to put a couple of nice dents in the wood without even really trying... not impressed...

I have an identical nose cone that I'm using on an upscale Thrustline Duster project which came out even worse, I'm still waiting for the stuff to cure so I can sand it smooth. I will NOT be using this stuff again. :hot:

 

[Buckaroo]

The basswood fins were pretty smooth to begin with, so they only got 1 coat of thinned down Elmer's Wood Filler. The nose cone got 2 coats, and today I shot a coat of primer. Looks like I'll get the paint on in time for Southern Thunder this weekend!

 

[Kaycee]

Great job on the up-scale, looks very nice!

I'm looking forward to seeing it fly this weekend at ST

 

[Buckaroo]

OK, I've been neglecting this thread, time to get things up to date. When we last left the "Big BS" (finally figured out what to call it) she was getting all prettied up for Southern Thunder 09.

The paint job came out semi-decent, the nice thing about gloss black is that it hides drips and runs prett well.

The last piece of required equipment showed up the day prior to ST09 in the form of a nice new spiffy chute from Spherachutes.

Ready to Rock! :headbang:

 

[Buckaroo]

Southern Thunder 09 summed up in two words... Freeking HOT!

If you were there, you know what I mean. I'm actually suprised nobody dropped in that heat (at least not that I heard about)

Saturday was all about my level 1 cert flight, prepping, flying, recovering, paperworking, cleaning up. By the time I was done it was early afternoon and I was baked. I finally recovered enough to get out the Big BS and prep her up. I built up an F52T-8 and headed to the pad. I tossed the Copperhead in the range box and bought a pack of FirstFire Jrs. Loaded her up, counted her down with the camera clicking away and... Nothing

Pulled the igniter, and saw that it had burned, put another one in and did it again... Nothing

Again the igniter had burned... asked some folks what they thought, "just make sure the igniter is all the way up in there" they said. So I did, last igniter in the pack, back on the pad... Nothing :hot:

Walking back to the car with three burnt igniters and an UNburnt motor trying to figure out what went wrong. Something in the instructions for assembling the motor floated to the surface of my cooked brain. I pulled out the paper and read step number 8 "Place a small piece of masking tape over the slot on one end of the propellant grain (E & F reloads only).... SONOFA... :bang:

I didn't have time to rebuild the motor, and since Sunday was low power day for me, Big BS did not fly at ST09

I did get a ton of cool on the pad pics like this... :roll:

 

[Buckaroo]

On a happier note, ST09 was not a complete waste for Big BS. She did meet her new best friend for life, Mr. Nom Nom Fish, who came home with us that weekend. Here we are re-hydrating from that adventure

 

[Buckaroo]

Flash forward to 11 July and the next MC2/HARA club launch. I was ready this time. No silly reloads, I had an F20W-7 Econojet loaded up and ready to go as soon as the pads opened up!

A few wispies of smoke and Boom! she was gone! Nice fast boost, arcing into the wind. Simmed to 1500 ft but probably a little less than that today due to the arcing flight profile. The delay was a bit long for a windy day, but deployment and recovery looked perfect. The wind actually brought her back pretty close. Looked like a great first flight! :clap:

 

[Buckaroo]

Unfortunately, things did not end up as nice as they appeared from the flight line. :y:

It's a clean split along the grain all the way down to the root and through the fillet. The forward section pulled away from the body tube partially.

 

[Buckaroo]

Nom Nom was not impressed...

 

[G2Rockets]

Hey Buckaroo,
Sorry to see the damage. Will you repair or rebuild?
What did you use for recovery?
Looked like a good flight if you subtract the ouchy.
John

 

[Buckaroo]

Hey Buckaroo,
Sorry to see the damage. Will you repair or rebuild?

Thanks, me to. Repair: it was such a clean break that it should be simple, I just need to sand off a little paint. Can't decide between CA or Epoxy, but I'm leaning towards CA because it seems to soak into the basswood better.

What did you use for recovery?

I had an 18" Hemispherical chute from Spherachutes, the descent rate didn't look too bad, but it was riding the wind pretty good and hit the ground going sideways faster than it was coming down. I've got a couple bigger chutes, I may try that.

Looked like a good flight if you subtract the ouchy.
John

Yeah I was pretty stoked until I pciked it up. This was my first real mid power build (although I jumped to HPR first) and I was hoping to fly it a couple more times that day. Oh well, the next club launch is in a week.

 

[Pem Tech]

Nom Nom was not impressed...

Yes, Nom Nom was taught to be a judge of fine rocket flesh, and to see such a beautiful rocket damaged so would bring much disappointment. Time to crack the glue and rehydrate a bit more.

 

[PemTech's Squeeze]

Good to see Non-Nom there! Looking a little thin though. Been him feeding his diet of nose cones with occasional spent motors? Give my baby Nom-Nom some cuddles from his mommy!

Trudy
PemTech Art Departement and defacto Booster
ps "home is where you wear your hat... I feel so breakup, I wanna go home." Catch you later Monkey-boy!