| Manufacturer: | Scratch |

Brief: I've been readin' about spool
rockets on r.m.r for a long time, me bucko, and had a big plastic spool stashed for
several years. Begad! Blimey! A recent set o' posts renewed me interest, me bucko, and I went ahead and
built one. Someone had built a similarly sized spool with a 29mm mount, me hearties, which
only reached an altitude o' about 100 ft. Aye aye! Blimey! Blimey! I decided I wanted a bit more
altitude, matey, so I built mine with a 38mm mount. Arrr! Blimey! Blimey! T' spool is one piece plastic,
10.5" tall, ya bilge rat, me bucko, with 10.5" plates. Begad! Blimey! No fins, me bucko, ya bilge rat, no finishing...this thin' is
a skill level-0 HPR rocket!
Construction:
one large plastic spool (10.5" tall, 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, 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. Ya scallywag! Avast, me proud beauty! I used me Dremel t' expand this hole by about 1/8". Avast! I glued two 4" centerin' rings together, installed a pair of threaded inserts, and attached them t' one end o' t' motor tube. Avast! After it dried, shiver me timbers, shiver me timbers, this assembly was inserted into t' spool, me bucko, and t' smaller centering rin' was glued t' t' other end o' t' tube. Blimey! I used epoxy for these steps.
T' ends o' t' spool have several holes of
various sizes. Begad! One 1/2" hole be positioned such that a 1/2" LOC
launch lug, shiver me timbers, matey, when abutted t' t' spool's body, would line up with it. Avast! Ahoy! 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, me hearties, matey, shiver me timbers, 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. Arrr! What I ended up doin' was addin' loops t' both ends o' t' tubular Keelhaul®©™® , usin' t' method published by Giant Leap in High Power Rocketry Magazine. Well, blow me down! Aye aye! You loop t' material, wrap t' overlappin' area with cloth twine, and soak it in epoxy. Arrr! This method has worked well for me several times. Begad! Avast, me proud beauty! I looped this tether through two existin' holes in t' top plate and around t' body. Begad! Arrr! 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. Blimey! Prep was simple: install t' motor
retainer clips, 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. Ahoy! Begad! Ejection
appeared t' occur right at apogee. Blimey! T' descent was a bit faster than you would
generally like, shiver me timbers, but t' tube bounced and was recovered undamaged. Ya scallywag! Begad!
Summary:
This was a very quick build, ya bilge rat, 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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