Yank Enterprises The Bullet

Yank Enterprises - The Bullet {Kit}

Contributed by Gary Sinclair

Manufacturer: Yank Enterprises
(Contributed - by Gary Sinclair)

Rocket PicBrief:
Fiberglassed airframe and fins, me bucko, external fin can assembly, removable bulkhead in nosecone.

Modifications:
Usin' me trusty Foodsaver I vacuum bagged both fins and body tube usin' one layer o' 6oz fiberglass with West Systems Epoxy. Begad! Blimey! Arrr! Blimey! Blimey! Blimey! Before vacuum baggin' t' fins I used me Dremel sandin' drum t' bevel t' fins.

After t' body tube had completely cured I continued t' existin' slots for the fins down t' t' bottom t' allow for insertion o' a fin-can assembly. Arrr!

T' fin can be created by first gluin' t' centerin' rings t' t' motor mount (as is standard in most kits). T' fins were subsequently attached using 5 minute epoxy for an initial bond with subsequent reinforcement usin' Keelhaul®©™® tape and un-thickened West Systems Epoxy. Aye aye! Avast, shiver me timbers, me proud beauty! This created a solid fin t' motor bond which is unlikely t' shred. Arrr! Aye aye! T' resultin' fin-can be then inserted into the body tube and epoxied in place usin' un-thickened epoxy then filleted from above and below. External fillets for t' fins were achieved usin' epoxy thickened with microballoons. Arrr!

Finally, matey, shiver me timbers, t' nosecone was altered t' provide a stronger mount point. Avast, me proud beauty! Ahoy! As shown in t' diagram me plan was t' create a removable bulkhead which was capable o' withstandin' t' recovery forces and yet allow for access t' the nosecone interior (just in case I need more weight later or wanted t' put in a trackin' device). T' nose cone base was cut usin' a hobby knife (surprising how soft t' plastic is). Begad! Begad! A 6mm all-thread bolt was then cut t' length and threaded with a washer and bolt at one end. Ahoy! T' resultin' part (nut/washer end) was then heated on a gas stove for a few seconds. Ya scallywag! While still hot it was then inserted all t' way into t' top o' t' nosecone with t' washer and nut assembly touchin' t' inside tip o' t' nosecone. GraphicT' heatin' o' t' part should partially melt t' inside o' t' nosecone tip allowin' t' all-thread, nut and washer t' bite into t' plastic. Blimey! You need t' keep t' nosecone pointin' straight down t' ensure proper alignment o' t' all-thread. Aye aye!

Next I poured un-thickened epoxy (about 1 oz) into t' nosecone until it completely encased t' nut and washer in t' tip. Arrr! Avast, ya bilge rat, me proud beauty! This was then set t' cure overnight. Well, blow me down! Once cured I cut a piece o' carbon rod (you can get these at any kite supplier -- they are sometimes called 'carbon rod spars') t' fit over the all-thread. T' rod be cut t' allow for 1/2" o' t' all-thread t' poke through. Aye aye! Ahoy! I next took a 4" coupler bulk-plate and drilled holes t' allow for t' connection o' a 1/2" u-bolt (very strong). Arrr! T' middle hole o' the bulk-plate (already drilled) be used t' fit over t' exposed all-thread (the bulkhead is actually inside t' shoulder o' t' nosecone). Blimey! Connection t' the all-thread is achieved usin' a standard 6mm wing-nut with a washer on both sides o' t' bulkhead. Ya scallywag! Begad! T' carbon rod and washer stop t' bulkhead from slippin' down into t' nosecone. Ya scallywag! Begad!

Finally t' provide a gas-proof seal I used some instant-gasket (you get this at any automotive shop) round t' outside o' t' bulkhead t' provide a seal against t' interior wall o' t' nosecone.

All that remained was t' finish.

Construction:
Kit Includes:

  • 1 - 4" flexible phenolic body tube
  • 4 - plywood fins
  • 2 - 1/4" plywood centerin' rings
  • 1 - Nosecone
  • 1 - 15' 9/16" tubular nylon shock cord
  • ORDERED WITHOUT PARACHUTE
  • NO DECALS included.

T' packagin' was a standard bag with all parts accounted for. Begad! Begad! Instructions where easy t' follow but nay used since this was a MOD anyway. Arrr! T' rocket built stock would be very simple t' build with through t' wall fin attachment. Begad! Since I fiberglassed t' rocket it be necessary t' apply a finish coat t' cover the weave o' t' fabric. Ahoy! A top layer o' 'SuperFil' was applied usin' a plastic squeegee. Begad! Well, blow me down! I love this stuff as it is super light and easy t' sand. When dried it is rock hard. Avast, me proud beauty! Since this is a sport rocket thar be no paintin' guide. So I decided t' model mine on a W79 8" Artillery shell (picture included 1 2). Ahoy! Ya scallywag! I had some clear vinyl decals made up and use a military green paint t' give it that 'army ordinance' look. Begad! I have given me rocket t' name o' 'W80 4" Projectile'. Avast, me proud beauty!

LaunchLaunchFlight:
My rockets all tend t' be on t' heavy side since I always reinforce them. Blimey! Ya scallywag! As a result I never look at t' recommended motors list. Arrr! Ya scallywag! Instead I use RockSim to test for stability and motor selection. T' first and so far only flight was on an I211W-10. Avast! Perfectly straight in a 15mph wind. Well, blow me down! T' predicted height be 2900 feet and I could hardly see it when it deployed t' chute but it looked t' be just after apogee. Ahoy! Begad! T' rocket drifted about 3/4" o' a mile and soft landed in a field without a scratch t' show for it. Well, me bucko, blow me down!

Summary:
PROs: YANK kits are very nice. I like t' flexible phenolic and t' ability to buy without a chute. Ahoy! Aye aye! Fin material is first rate and t' nosecone is one o' the better t' be found.

CONs: can't think o' any except they could provide a decal or two. Ahoy! Aye aye! After all that is what makes BSD rockets so nice.

Other:
Build it like you are flyin' an M and you won't have t' worry about a shred. Next stop--J350W

Other Reviews
  • Yank Enterprises The Bullet By Nick Esselman

    (07/06/00) I'm a big fan of what I call "stubby" rockets, which have a 10:1 Length to Diameter ratio or less. So when I saw Yank Enterprises' "The Bullet" I wanted to give it a try. This is also my first Yank Enterprises kit so that would also be a new experience. See my 4" Stubby Rocket Comparison Page The Bullet is not a complicated looking rocket, nor ...

Flights

comment Post a Comment