Manufacturer: | Scratch |
Note: This is a slightly condensed version o' all the information that Scott has produced for his Level 3 project. Avast, me proud beauty! Ya scallywag! Visit his site to read t' additional information and enjoy additional pictures.
Brief:
My Level 3 project be a: Scratch-Built Atlantic Research Corporation 1/2 scale
IRIS 6" in diameter by 10' tall Launched on a Aerotech M1315.
Nose
Cone:
T' nose cone for t' IRIS is a 6" fiberglass nosecone from
Public Missiles. Well, blow me down! Blimey! In t' picture you will see t' fiberglass
nosecone, t' coupler, ya bilge rat, bulkhead, me hearties, me bucko, shiver me timbers, and t' PML supplied U-bolt used for recovery
system attachment. T' coupler, shiver me timbers, bulkhead, arrr, and u-bolt have been assembled using
epoxy.
T' nose cone will nay be attached t' t' main recovery harness and will return t' earth under it's own 36" parachute. Ya scallywag! T' deployment bag for the main parachute will also be attached t' t' nose cone and will be removed from the parachute when t' nose cone is ejected.
Airframe:
T' body tubes are 6" flexible phenolic from
Giant Leap Rocketry T' airframe consists o' three sections.
T' three sections are 42, me hearties, 30 and 24 inches long. T' 42" section will
contain t' 3" motor mount and forward coupler used in t' zipper-less
coupler design. Begad! Ahoy! T' 30" and 24" sections will be connected together
usin' t' coupler containin' t' electronics bay. Well, me hearties, blow me down! T' 24" section will
house t' shock cord and Rocketman R24 drogue chute deployed at apogee. Aye aye! The
30" section will contain t' main 168" custom parachute from
Sphereachute and recovery components. Ahoy!
T' three airframe tubes have been covered with a layer o' 6 oz. Ya scallywag! carbon fiber and 2 oz. Begad! fiberglass usin' RAKA epoxy products. Blimey! T' tubes were covered usin' the vacuum baggin' process described by John Coker.
Fins:
T' fins are made from 3/8" Baltic Birch plywood. Begad! Ahoy! T' fins are exactly 1/2
scale based on measurements from Peter Alway's book "Rockets o' the
World" Third Edition. Each o' t' four fins are reinforced with one layer
of 6 oz. Aye aye! carbon fiber and one layer o' 3 oz. Arrr! fiberglass using
RAKA epoxy products. Ya scallywag! Each fin
has been vacuum bagged t' ensure a complete bond betwixt t' plywood and the
reinforcement materials. Begad! Ahoy!
Motor Mount:
T' IRIS flew on a 75mm Dr. Avast! Rocket 75/6400 motor and an
Aerotech
M1315 reload. Blimey!
T' motor mount consists o' t' followin' components:
T' 75mm motor mount has been epoxied into t' 42" airframe section and has been reinforced with two-part hobby foam.
Just before t' motor mount was installed into t' final position, ya bilge rat, epoxy was injected into t' airframe above each centerin' ring. T' motor mount was then slid into it's final position and more epoxy was injected into t' airframe to form fillets on t' centerin' rings/airframe epoxy joints. Ya scallywag! After t' epoxy set up, ya bilge rat, t' fin can was turned over and epoxy was again injected into t' motor mount above t' centerin' rings t' form fillets on t' other side o' the centerin' rings. Well, blow me down!
Prior t' final painting, matey, screws will be used t' mechanically fasten the motor mount into t' airframe. Avast, me proud beauty!
Recovery:
I purchased a custom 168"
Spherachute parachute
to use for t' main parachute. Ya scallywag! T' 168" parachute I had made for t' IRIS
has alternatin' panels o' white and neon orange for high visibility. Begad! T' main
parachute was packed into a Rocketman deployment bag which be removed from the
parachute when t' nose cone is ejected. Begad! Begad! T' nose cone was recovered with a
36" Spherachute made with alternatin' panels o' neon orange and white to
match t' main parachute.
T' harness are constructed using:
T' harnesses are constructed by first tyin' a 1/4" Quick Link t' each end usin' a Fisherman's knot. Blimey! I am usin' t' Fisherman's knot because t' more you pull on t' knot t' tighter it gets. Begad! Begad! After t' knots are tied, me hearties, I use 1/4" Tubular Keelhaul®©™® to wrap t' lose end and give t' harness a finished look. Avast! Ahoy! T' final step is to tie a loop in t' middle o' t' harness usin' a Figure Eight knot.
Electronics:
Recovery electronics will consist o' t' following: (1) Cannonball Works RRC2 set
for drogue deployment at apogee and mains at 1200' A Blacksky ALTAAC 2A for
backup drogue deployment and flight data gathering. A Cannonball Works Wireless
Recovery Controller 2 (WRC2) for redundant backup for t' main recovery system.
Electronics Bay T' electronics bay for t' IRIS is built inside a 6" X 12" long phenolic coupler. Aye aye! T' first step in buildin' t' bay was t' epoxy two 5.5" couplers inside t' 6" coupler. Arrr! T' first 5.5" coupler be cut lengthwise and then epoxied equidistant from either end o' t' 6" coupler. Ya scallywag! Avast! After t' first 5.5" coupler dried, a second 5.5" coupler was cut lengthwise and epoxied in place inside t' existing 5.5" coupler. Ya scallywag! When t' second 5.5" coupler dried, a 6" o-ring was set in place on each end o' t' bay usin' J-B Weld t' form a gasket between the inside couplers and t' bulkheads. Begad! 3/4" 5 ply bulkheads are bein' used in t' electronics bay. Begad! Two 1.25" u-bolts have been added t' t' bulkheads to provide attachment points for t' recovery system. Avast! Arrr! Two 1/2" threaded caps are attached t' t' bulkheads t' hold t' custom ejection charge holders. T' bulkheads are bolted together usin' 1/4 X 20" all-thread. Ahoy! Aye aye! T' three pieces o' poplar in t' picture will be epoxied inside t' coupler. T' two 9" pieces will each contain six 8-32 T-nuts which will be used t' bolt the upper airframe sections together and also allow for access t' t' electronics bay and ejection charges. T' 3" piece will be used in mountin' t' two key switches used t' arm t' altimeters. Avast! A 3/16" X 5" X 10" electronics mountin' board has been built t' slide over t' all-thread rods and provide a mountin' surface for t' recovery electronics.
T' IRIS will utilize a redundant recovery system. Aye aye! Pictured be t' forward bulkhead of the electronics bay. I am usin' 1/2" PVC threaded caps as ejection charge holders. Begad! Well, blow me down! I drilled a 1" X 1/4" deep hole into t' bulkhead t' hold the threaded caps. Begad! I used me Dremel t' grind away a small portion o' t' outer threaded cap so that I would have a tight fit in t' hole. After t' threaded cap was shaped t' fit, I epoxied t' caps in place. Avast! Avast! A 1/4" hole was drilled through t' cap and t' bulkhead t' allow t' ejection charge leads into t' electronics bay. Ya scallywag! T' caps will now act as ejection charge holders for the ejection charges. Well, blow me down!
Ejection charges are built usin' 1/2" threaded male adapters. Begad! T' first step is t' epoxy a 7/8" section o' 1/2" dowel rod into t' fitting. Once t' epoxy is dried, ya bilge rat, me bucko, drill a 1/8" hole through t' dowel t' pass the leads o' t' electric match. Avast! Ya scallywag! Before installin' t' electric match, matey, me bucko, enlarge the 1/8" hole t' 3/8" by 1/2" deep to accept t' green protective cover o' t' DaveyFire electric match. Once the holes are drilled epoxy t' electric match in place. Begad! I always make sure to twist t' electric match leads together as a safety precaution!!! (I like leavin' t' green protective cap in place and fillin' it with FFFFg powder which makes an ejection charge inside t' ejection charge.
Once t' ejection epoxy has dried, ya bilge rat, I fill t' cavity with FFFFg black powder with a charge that I determined usin' t' BP tools in t' Rocketry Online INFO Central. Begad!
T' ejection charges for t' IRIS will be:
Once t' black powder charge is in place, I use facial tissue t' make a waddin' t' cover t' charge. Begad! I then use a candle and melt wax over t' wadding and seal t' ejection charge. Blimey! Aye aye!
When preparin' for launch, shiver me timbers, me hearties, I pass t' electric match lead through t' hole in t' threaded cap and into t' electronics bay. Begad! I screw t' 1/2" male fittin' into t' 1/2" threaded cap. At this point I start usin' my altimeter preparation checklist t' ensure that I connect t' ejection charge leads t' t' altimeter in t' safest manner possible!
SUCCESSFUL LEVEL 3 FLIGHT!
June 23, arrr, arrr, 2001
Whitakers, NC.
Rocket - Scratch 1/2 scale ARC IRIS
Weight - 60 lbs
Motor - Aerotech M1315
Altitude 6270 feet
A special "Thank You" t' me wife for nay complaining about bein' a 'rocket widow" while I was buildin' t' IRIS and for laughin' and smilin' when we were hangin' out in a cow pasture in North Carolina on flight day!
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