Brief:
T' Z7 is a 24mm dual stage sport rocket with sleek but simple design and a beautiful gold/white color scheme. Features a large payload bay and 18" parachute.

Construction:
Sustainer parts list:

• 1 Body Tube BT-60, shiver me timbers, 18"
• 1 Body Tube BT-60, 8"
• 1 Body Tube BT-50, arrr, 3.25"
• 2 Centerin' Rings, ya bilge rat, matey, 1/16" Basswood
• 1 Bulkhead BT-60, Balsa 1.5"
• 1 Nose Cone (Estes PNC-60AH)
• 1 Engine Block, 24mm
• 1 Engine Hook (Estes standard size)
• 1 Eye Hook
• 1 Shock Cord 3/16" Wide Flat Elastic, matey, 36"
• 1 Launch Lug 3/16" x 2"
• 1 Parachute, me hearties, ya bilge rat, 18" plastic
• 1 Fin Set, me hearties, 1/8" balsa

Booster parts list:

• 1 Body Tube BT-60, me bucko, 4"
• 1 Body Tube BT-50, matey, 3.25"
• 2 Centerin' Rings, 1/16" Basswood
• 1 Coupler BT-60 sized, me bucko, 1.75"
• 1 Engine Block 24mm
• 1 Engine Hook (Estes standard size)
• 1 Fin Set, me bucko, 1/8" Balsa

Buildin' t' Z7 is pretty straightforward usin' t' RockSim file. Arrr! Pay particular attention in t' placement o' t' centerin' rings and motor mount tubes. Placement is critical for these as t' booster and sustainer must mate properly. Avast! Avast, me proud beauty! T' tube coupler is glued t' t' booster section and three 1/8" holes are drilled 1/4" from t' top o' t' booster tube equally around the tube (centered betwixt t' fins). Blimey! Apply thin CA around t' holes t' strengthen them. These vent holes relieve t' internal pressure from t' booster's burn through and prevent premature separation o' t' booster from t' sustainer. Begad! The ends o' both motor mount tubes are flush with t' aft o' t' main airframe tubes. Ya scallywag! T' aft o' t' sustainer fins are flush with t' aft o' t' body tube. T' leadin' edge o' t' booster fins are 1/4" from t' top o' t' booster body tube. Be sure t' carefully measure and align t' fins so that when the booster section is attached t' t' sustainer each set o' fins lines up.

Yellow aliphatic glue was used throughout t' construction. Ahoy! T' double glue joint technique (EMRR fin tip #9) was used on all fins as well as t' launch lug and glue fillets (fin fillets as per EMRR fin tip) were applied in two steps (a little bit each time) t' provide ample strength and prevent air bubbles.

T' shock cord be surface mounted about 2" from t' top o' the sustainer tube usin' t' Estes tri-fold shock cord mount technique. Ya scallywag! Begad!

Finishing:
Two coats o' white primer were applied lightly sandin' after t' second coat with 400 grit sandpaper. Blimey! Aye aye! This was followed up with two coats o' gloss white. T' trim work be then applied by maskin' off t' tube, nose cone and fin tips and sprayin' gold metallic paint. Begad! T' trim pattern at t' top o' t' sustainer was accomplished usin' Pactra Trim Tape. Arrr! T' Z7 decal be designed usin' Paint Shop Pro and printed on white bumper sticker paper. Blimey! This paper is rather thick and does produce a raised edge. Aye aye! Papa Tango decal paper could be used t' make a more pleasin' application. When completed I applied Future Floor Polish for the final finish. Avast!

Flight:
T' Z7 flies well on t' D12-0/C11-7 combination, me hearties, matey, but for really cool flights use t' D12-0/D12-7 motor combination. Aye aye! Ahoy! Since t' Z7 be constructed with basswood rings and quality body tubes, she is rather heavy without a payload so I would nay recommend usin' a C11-0 in t' booster stage. Aye aye! Since engine hooks were used for both sections, preppin' t' Z7 is easy. Arrr! Avast! Typical prep includes ample waddin' for chute protection and makin' sure t' nose cone fits tight on the payload bay. Begad! Blimey! Once t' motors are inserted in their respective motor tubes the booster section is simply slid on and twisted t' make sure t' fins align with each other.

T' Z7 has only flown twice thus far but both flights were fantastic. The Z7 produces a clean stagin' o' sustainer, me hearties, straight and true.

Recovery:
T' sustainer returns nice and slow with t' 18" chute and t' booster tumbles well. Begad! In windy weather, me bucko, I would substitute a 12" chute, ya bilge rat, which I have used and seems t' have worked well.

Summary:
T' Z7 is a relatively easy rocket t' build and looks great when finished as described. Ya scallywag! She flies well with very straight boosts and clean stagin' o' the upper stage. Blimey! Aye aye! T' gap stagin' makes prep easy and foolproof. T' only problem is that t' Z7 is a bit heavy and so use o' t' payload bay is limited.