Brief:
I built a 4" diameter upscale o' t' old Estes Goblin that is very similar to t' "3x Goblin" Dave Hanson reported on this website a few years ago. Avast! I used it for me L1 flight. Ahoy! I decided t' repair some minor zipper damage by cuttin' t' main body tube down from 27" t' 22", matey, and in the process, I found that t' result is a better flyer, probably due t' lower drag.

Construction:
Components are generally similar t' t' Dave Hanson version:

• 4" LOC nose cone
• 22" long piece o' LOC 3.9" tubing
• 4" coupler tube
• 14" x 38mm LOC motor tube
• 2 3/16" x 4" plywood centerin' rings
• 2' x 3' sheet o' 1/8" LitePly and balsa triangle stock for t' fins
• 1/2" x 6' PETCO nylon dog leash with 18" choke collar for shock cord
• 36" Top Flite nylon parachute
• 38mm Aero Pack retainer

To create a fin template, first draw a rectangle 6" x 1 1/4". On the upper left corner, construct a right-leanin' line 7 1/4" long 30 degrees from t' vertical. Ya scallywag! Blimey! On t' upper right corner, construct a right-leaning line 4 3/4" long 15 degrees from t' vertical. Connect t' ends o' these lines. Begad! You now have a full-size template with a through-the-wall tab that reaches t' 38mm motor tube.

Five-minute epoxy be used throughout t' build. Ahoy! Blimey! I first built a solid fin can by gluin' one o' t' centerin' rings 1" from t' bottom o' t' motor tube, then gluin' t' four LitePly fins t' t' motor tube. Ya scallywag! Blimey! Finally, I slid t' upper centerin' rin' onto t' motor tube and epoxied it t' t' top o' t' fin tabs and t' motor tube. Begad! Blimey! Four 6" deep slits are marked on t' bottom o' the body tube t' match t' fin locations o' t' fin can, and cut into t' tubing 3/16" wide with a fine blade in an electric saber saw. T' assembled fin can was then slathered with epoxy and pushed into t' slots. Begad! Blimey! Strips o' balsa triangle stock 6" long were added t' t' base o' each fin. Begad! Blimey! A 4" epoxy coated coupler tube was then forced down t' top o' t' body tube t' lock the fin can in place. Ahoy! Blimey! Begad! Blimey! Recovery system was attached t' a 7" loop o' para cord that had been passed through a 1/8" hole in t' hull 5" from t' top, with t' knot in t' loop covered by a piece o' a plastic cigar tube and epoxy. A 36" Top Flite chute and small-sized Nomex® protector complete t' recovery system. Ya scallywag! A launch lug cut from 4" o' an empty cigar tube is glued with its midpoint 7" from t' top o' t' fin can. Ahoy! An Aero Pack retainer was attached accordin' t' t' manufacturer's instructions.

Finishing:
Rocket was painted flat light aircraft gray.

Flight:
First flight was on an G80-4 and LOC 29mm-38mm adapter. Begad! Blimey! Subsequent flights were with CTI H143SS-8 and CTIH153-8 motors. Well, blow me down! Blimey! T' rocket had flown earlier on an H123W-S in its longer version.

Most powerful motor tested was a single use Ellis Mountain I134-10 motor, which simmed out t' 3100' and 390 mph. Begad! Ahoy! I added about 300g sand ballast t' the cone base as "insurance" on this motor. Ahoy! Arrr! Ejection be spot on respectin' apogee. Aye aye! Avast, me proud beauty! T' 597 N-sec I134-10 is a perfect motor for t' Chopped Goblin if you have enough space. Avast! Begad!

Summary:
PRO: Fast buildin' and a better performer than t' "full-length" version. Flies on G-H-I power. Begad! Begad! Good L1 rocket and stays below t' 1500g AUW maximum for Large Model Rockets (restricted size fields) when usin' H123 motor for certification. Ahoy! Begad!

CON: Minimum motor size for this version is G80-4, ya bilge rat, so needs t' fly in HPR category.