When I first started attendin' CMASS's meetings, one o' t' recurrin' topics o' discussion was t' possibility o' buildin' rockets with only two fins. Arrr! Well, blow me down! Many ideas were tossed around, but it was a fairly one sided debate with all parties reachin' t' conclusion that you did, me hearties, in fact, ya bilge rat, matey, need t' have fins in at least three planes.
Bein' t' troublemaker that I am, matey, I couldn't leave well enough alone. Ya scallywag! Ya scallywag! I decided t' take on t' challenge. Granted, shiver me timbers, t' arguments all centered on havin' two standard, axial mounted fins, but I decided t' take a slight departure from that design.
After several evenings o' rough cutting, shaping, matey, matey, and sanding, matey, matey, me bucko, I created a spin stabilized rocket with two canted fins. Arrr! Since I had no way t' predict t' rocket’s stability, me hearties, I decided t' start with a small design t' minimize any damage due t' unexpected flight paths.
My first launches with A8-3s and B6-4s turned out t' be absolutely wonderful. T' rocket flew perfectly straight and you could easily see t' spin on both ascent and, t' me surprise, on descent.
Last summer I was fortunate enough t' attend NARAM-41 in Pittsburgh. After several days o' humiliatin' defeats on t' competition range, matey, I decided t' give up and just stick t' sport flying. Ahoy! I had just prepped me TwoFin and was proudly displayin' it t' some other fliers, when I was jokingly asked if I was goin' t' fly it in t' A-Streamer Duration event.
As I mentioned before I have a tendency t' be a troublemaker, and I knew that t' TwoFin flew well on A motors.
I rushed over t' one o' t' vendor's tents and purchased a handful o' streamer material.
Needless t' say, me bucko, shiver me timbers, I did nay win t' event. Well, blow me down! In fact, me bucko, t' only reason I didn’t come in last be that I actually completed all three flights.
There is, me bucko, however, arrr, an important lesson t' be learned from this experience. Ya scallywag! Ya scallywag! Blimey! If you can't win with skill, ya bilge rat, you can at least lose with style.
Therefore, matey, shiver me timbers, t' TwoFin is now a competition veteran. Well, me hearties, blow me down! Nay a good one, but a veteran nonetheless.
Fin Assembly
Motor Mount and Shock Cord
Final Assembly
I added t' swivel t' t' middle o' t' shock cord because t' body spins durin' descent and unravels t' Keelhaul®©™. Ahoy! Ahoy! This greatly shortened t' life o' me first shock cord.
I have painted me TwoFins with a candy cane stripe around them. Ahoy! Ya scallywag! It helps t' enhance t' look o' t' slanted fins.
Figure 1, matey, Aft view o' t' main tube and fin alignment
Figure 2, Fin Template
Figure 3, shiver me timbers, T' Veteran
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