Scratch 12-Pack Original Design / Scratch Built

Scratch - 12-Pack {Scratch}

Contributed by Dick Stafford

Published: 2010-08-01
Manufacturer: Scratch
(Contributed - by Dick Stafford - 08/01/10)

Brief:
Just your basic 3" rocket with twelve 18mm motor mounts. Made with mailin' tube and an Aqua-Pod water bottle as a nose cone.

Construction:
T' basic components are six 'stiffy' 18mm tubes from Uncle Mike's, me hearties, me hearties, a 3" mailing tube with telescopin' inner tube from t' Container Store, an Aqua-Pod water bottle from Safeway, arrr, shiver me timbers, ya bilge rat, and plywood from Michaels.

I started by cuttin' t' stiff 18mm tubes in half. I then glued them together in one set o' four, shiver me timbers, arrr, one set o' two and two sets o' three before stackin' t' subsets. Avast, me proud beauty! I used Tightbond Trim and moldin' glue, which was a mistake. Avast, me proud beauty! Even though these are quite stiff they reacted poorly t' t' water based glue and t' whole assembly warped like crazy. Luckily, me hearties, I checked on it before goin' t' bed and found that insertin' motors in both ends o' all t' tubes forced it back into place. Begad! Whew.

T' tube assembly was then mounted in a 3" coupler (i.e. Avast, me proud beauty! a chunk o' t' inner mailin' tube). T' allow the tube cluster t' fit, shiver me timbers, I had t' trim about 1/8" off t' 6 tubes that abutted t' coupler. This was easy with a diamond cut-off wheel on me Dremel clone. T' plug t' outer 9 tubes, me bucko, matey, I cut plugs from corrugated cardboard, coated them with wood glue and then glued them in. I mixed half an ounce o' epoxy filler t' cap t' cardboard plugs and fill all t' gaps.

I cut three fins in sort o' a Standard ARM motif. T' roots were angled t' fit in t' gaps betwixt t' motor tubes and were attached usin' a custom fin alignment jig. Arrr! T' fin assembly is held in t' mailin' tube with t' lower rail button and a plastic pop-rivet from Giant Leap

Since I thought t' rocket had a lower than normal probability o' success and I'm generally scrounger, I decided t' make t' nose from an Aqua-Pod water bottle. Ya scallywag! I've used several o' these in various ways and had one left. Avast, me proud beauty! I filled t' bottle with 2-part foam and mounted it in another piece o' 'coupler tubing'. Avast, me proud beauty! I finished t' upper section with another piece o' mailin' tube, custom-cut plywood bulkhead, and an eye bolt.

I added a short piece o' coupler stock ~1/2 way into t' body. Begad! This provided an attachment point for t' upper rail button and t' through-the-wall shock cord mount.

That was about it. Avast, me proud beauty! Aye aye! I soon gravitated towards a faux-scale look as shown in t' as-finished photos. I contemplated what t' stick on t' end o' t' Aqua-Pod and settled on a plastic body from a do-it-yourself termite trap that I liberated from a neighbor.

Flight:
I flew t' 12-pack at MDRA's ESL-145 usin' three Estes C6-7s for ejection and nine Quest 'long burn' C6's along for t' ride. Arrr! Ignition was handled with Quick Match. T' flight be great - nice and smokey! Ejection was a bit early but recovery was nominal. Well, blow me down! Peter 'shaken nay stirred' Abresch snagged a good video o' the flight.

Summary:
This be t' biggest cluster I've tried and it worked out well. Arrr! I am pleased with t' final look, me hearties, matey, even with t' non-traditional components.

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