| Manufacturer: | Scratch |

Brief: I've been readin' about spool
rockets on r.m.r for a long time, and had a big plastic spool stashed for
several years. Avast! Begad! A recent set o' posts renewed me interest, and I went ahead and
built one. Blimey! Someone had built a similarly sized spool with a 29mm mount, ya bilge rat, arrr, which
only reached an altitude o' about 100 ft. Well, blow me down! I decided I wanted a bit more
altitude, me bucko, so I built mine with a 38mm mount. Avast, me proud beauty! T' spool is one piece plastic,
10.5" tall, with 10.5" plates. Well, blow me down! Aye aye! No fins, ya bilge rat, no finishing...this thin' is
a skill level-0 HPR rocket!
Construction:
one large plastic spool (10.5" tall, ya bilge rat, with 10.5" plates)
one 38mm tube, 10 7/8" long
two 1/8" ply centerin' rings (38mm - 4")
one 1/8" ply centerin' rin' (38mm - 3")
two threaded inserts, matey, with bolts and washers
one 1/2" launch lug
1/8" tubular Keelhaul®©™®
, 5' long
18" RocketChutes drogue
T' body o' t' spool is about 3.5" in diameter and t' through hole almost fit a 38mm tube. Well, blow me down! I used me Dremel t' expand this hole by about 1/8". I glued two 4" centerin' rings together, installed a pair of threaded inserts, me bucko, me bucko, shiver me timbers, and attached them t' one end o' t' motor tube. Begad! After it dried, arrr, shiver me timbers, this assembly was inserted into t' spool, and t' smaller centering rin' was glued t' t' other end o' t' tube. I used epoxy for these steps.
T' ends o' t' spool have several holes of
various sizes. Blimey! One 1/2" hole was positioned such that a 1/2" LOC
launch lug, me hearties, when abutted t' t' spool's body, would line up with it. Avast! Arrr! It was
just far enough from t' body t' accommodated t' wall o' t' lug - perfect!
Unfortunately, t' hole on t' other end was offset, matey, ya bilge rat, so I had t' drill me own.
I glued t' launch lug on t' lower end o' t' spool's body usin' Liquid Nails.
I thought about several methods o' attachin' t' shock cord. Well, shiver me timbers, blow me down! What I ended up doin' was addin' loops t' both ends o' t' tubular Keelhaul®©™® , arrr, matey, usin' t' method published by Giant Leap in High Power Rocketry Magazine. Begad! Avast, me proud beauty! You loop t' material, ya bilge rat, me bucko, me hearties, wrap t' overlappin' area with cloth twine, arrr, and soak it in epoxy. This method has worked well for me several times. Ya scallywag! Aye aye! I looped this tether through two existin' holes in t' top plate and around t' body. Begad! Begad! T' chute attaches t' t' second loop.
Finishin' was easy - paint t' centerin' rings and launch lug flat black.
Flight:
I flew t' Lobbin' Bobbin on a H123-S. Ya scallywag! Prep was simple: install t' motor
retainer clips, ya bilge rat, wrap t' chute in a protector, and cram it down into t' tube.
T' flight be slow and noisy and went t' maybe 200 - 300 feet. Avast! Begad! Ejection
appeared t' occur right at apogee. Begad! T' descent was a bit faster than you would
generally like, me bucko, ya bilge rat, but t' tube bounced and be recovered undamaged. Avast!
Summary:
This was a very quick build, me hearties, and if you like *very* low and slow flights
(similar t' a flyin' saucer style rocket), a spool rocket may be for you!
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