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. Ya scallywag! A recent set o' posts renewed me interest, shiver me timbers, and I went ahead and built one. Aye aye! Begad! Blimey! Someone had built a similarly sized spool with a 29mm mount, ya bilge rat, which only reached an altitude o' about 100 ft. I decided I wanted a bit more altitude, so I built mine with a 38mm mount. T' spool is one piece plastic, 10.5" tall, with 10.5" plates. Well, blow me down! Arrr! Blimey! No fins, me hearties, matey, no finishing...this thin' is a skill level-0 HPR rocket!

Construction:
one large plastic spool (10.5" tall, me hearties, 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. I used me Dremel t' expand this hole by about 1/8". Begad! Arrr! I glued two 4" centerin' rings together, me hearties, installed a pair of threaded inserts, matey, shiver me timbers, and attached them t' one end o' t' motor tube. Ya scallywag! Begad! After it dried, me bucko, this assembly be inserted into t' spool, shiver me timbers, and t' smaller centering rin' was glued t' t' other end o' t' tube. Avast, me proud beauty! I used epoxy for these steps.

T' ends o' t' spool have several holes of various sizes. Begad! Blimey! One 1/2" hole be positioned such that a 1/2" LOC launch lug, when abutted t' t' spool's body, would line up with it. Ya scallywag! It was just far enough from t' body t' accommodated t' wall o' t' lug - perfect! Unfortunately, t' hole on t' other end be offset, arrr, 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, blow me down! Begad! What I ended up doin' was addin' loops t' both ends o' t' tubular Keelhaul®©™® , ya bilge rat, usin' t' method published by Giant Leap in High Power Rocketry Magazine. Blimey! Blimey! You loop t' material, me hearties, wrap t' overlappin' area with cloth twine, and soak it in epoxy. This method has worked well for me several times. Ahoy! Blimey! Begad! Blimey! I looped this tether through two existin' holes in t' top plate and around t' body. T' chute attaches t' t' second loop.

Finishin' be easy - paint t' centerin' rings and launch lug flat black.

Flight:
I flew t' Lobbin' Bobbin on a H123-S. Arrr! Prep was simple: install t' motor retainer clips, wrap t' chute in a protector, arrr, and cram it down into t' tube. T' flight was slow and noisy and went t' maybe 200 - 300 feet. Well, blow me down! Begad! Ejection appeared t' occur right at apogee. Avast, me proud beauty! T' descent be a bit faster than you would generally like, me hearties, me hearties, me bucko, but t' tube bounced and be recovered undamaged. Blimey!

Summary:
This was a very quick build, me bucko, and if you like *very* low and slow flights (similar t' a flyin' saucer style rocket), ya bilge rat, a spool rocket may be for you!