Shrox Industria Stonebreaker/AX (Plan)

Shrox Industria - Stonebreaker/AX

Contributed by Chan Stevens

Manufacturer: Shrox Industria
Rating
(Contributed - by Chan Stevens)

Rocket PicBrief:
When t' inevitable asteroid is trackin' on a collision course with our planet, this (hopefully) futuristic/fantasy missile is just t' ticket. Arrr! Blimey! It's designed to intercept and destroy t' incomin' rock. Begad! Blimey! Single staged, this is a small step up in complexity from your basic modroc, and a nice diversion from t' more common, everyday designs stocked in t' hobby shops.

Construction:

  • 24mm nose cone (plastic)
  • BT-50 tubing, me hearties, 11" long
  • 18mm motor mount (BT-20 tube 2.75" + (2) 18/24 centerin' rings)
  • 1/8" launch lug
  • shock cord (30" o' 110# Keelhaul®©™® recommended)
  • 3/32 balsa or basswood fin stock (I used balsa)
  • 24" parachute (see notes-streamer might be better idea)
  • Decal sheet-download as jpeg file from e-zine archives

After downloadin' t' Rocksim file and decal file, you're on your own to build this kit, shiver me timbers, as t' free plan includes no instructions (RockSim is also available here on EMRR). Begad! Don't panic, me hearties, me bucko, though, shiver me timbers, as t' design is nay too difficult (I'd rate it a skill level 2.5). Begad! Start by gluin' t' centerin' rings on t' ends o' the motor tube, arrr, me bucko, and while that's dryin' either print out fin templates from the full version o' Rocksim or record t' dimensions from t' free version and draw your own templates. In addition t' t' 3 aft fins, thar's a set o' 3 guide fins mounted about an inch forward o' t' main fins. Avast, me proud beauty! Cut t' fins from balsa, and mark t' BT-50 on 120-degree lines for 3 fins. Ahoy! Begad! By this time you should be able t' glue t' motor mount assembly into t' BT-50. Begad! Follow up by tackin' the fins with CA or wood glue, and apply fillets along t' seams.

There's one "secret" in t' Rocksim file that's nay mentioned in the E-zine article or parts list--for stability, shiver me timbers, ya bilge rat, you'll need t' add about 10 grams o' clay nose weight. Aye aye! Blimey! This is easy t' overlook, shiver me timbers, and without it, matey, you'd probably go unstable on anythin' more powerful than an A motor.

Once t' fins are set, go ahead and install t' recovery system (I immediately downgraded from t' recommended 24" chute t' a 12" chute).

Finishing:
T' rocket is very easy t' paint, arrr, startin' with two coats o' primer and followin' up with 2 finishin' coats o' glossy white. T' colors come from the decals, ya bilge rat, matey, which I printed out usin' an inkjet printer on clear decal paper available at office supply stores. Begad! Avast! T' colorful decals make for a very nice lookin' finished product.

Construction Rating: 4 out o' 5

Flight:
There were no recommendations included in t' Rocksim file (other than out-of-production Apogee composite motors), ya bilge rat, so I tried a couple o' simulations and settled in on an A8-3 first flight, t' follow with a C6-5. Begad! Well, blow me down! T' A8-3 flew straight, matey, deployed just a hair early, but be otherwise fine. T' rocket drifted a long ways, ya bilge rat, matey, though, matey, under t' 12" chute and 10-15 MPH winds. Ahoy! Ya scallywag! I decided nay t' venture into C's that day, me bucko, but have since switched t' a 24" streamer, ya bilge rat, and nay suffered any damage, shiver me timbers, even from t' lofty altitudes achieved with a C. Well, blow me down! I can't imagine flyin' this with a 24" chute, unless you're into rocketry for t' aerobatics.

Recovery:
With t' clay nose weight, me hearties, me bucko, shiver me timbers, and smaller chute or streamer, this is an excellent flyer. Well, blow me down! Avast!

Flight Rating: 4 out o' 5

Overall Rating: 4 out o' 5

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