Scratch DC-20 Digital Camera Rocket (light) Original Design / Scratch Built

Scratch - DC-20 Digital Camera Rocket (light) {Scratch}

Contributed by Morgan Hendry

Manufacturer: Scratch
DC-20 Digital Camera Rocket (light)
(Contributed - by Morgan Hendry) 

Rocket Pic This project be an extension o' me original DC20 camera rocket. Arrr! Ya scallywag! I has underestimated t' finished weight o' the Initiator rocket camera, thinkin' it could be lofted on an E t' 500'. Avast! Begad! Big mistake. Avast! Avast! T' finished weight be 2.2 lbs. An F engine would be needed t' reach t' same altitude. Aye aye! I read a thread on RMR concernin' a light weight rocket camera booster. Well, blow me down! It described a Estes Phoenix kitbash, matey, usin' traditional white glue construction, arrr, that should be able t' loft a camera on a D or E engine. Aye aye! Ya scallywag! I thought about it and decided on another approach. Blimey! I would use a minimum diameter section for t' 24mm motor tube (BT 50) and then a transition t' a 2.6" diameter payload tube (BT 80). As I was experimentin' with a BT 80 nose cone with an open bottom, I found that the electronics and about one half o' t' camera would fit inside a Fat Boy type cone. In theory, me hearties, me hearties, I could create a nose cone payload section out o' t' nose cone and a BT 80 transition section. Avast! Maybe for t' next rocket... Arrr! Aye aye!

Construction began with t' minimum diameter section. Aye aye! I glued (white glue) a BT 20/50 green centerin' rin' in a piece o' BT 50 body tube about 3" from one end. Blimey! This will allow me t' use Estes and Aerotech single use and reloadable motors. Avast, me proud beauty! When that dried, shiver me timbers, I glued a 3/32" basswood BT 50/80 centerin' ring on t' top o' t' motor tube (facin' t' front o' t' rocket). Well, blow me down! Below that, me bucko, I glued a 1" piece o' a BT 80 transition section, then another ring. The 2" long BT 50/80 transition section (made on VCP) was printed out, shiver me timbers, copied onto file folder material, cut out and glued on with white glue. Ahoy! Glue a screw eye in t' top ring. Avast! Aye aye! I used scraps o' basswood t' stack on top o' one another to make a thicker joint. Begad! This completes t' lower section except for t' fins (which I still have t' do). Well, blow me down!

Rocket Pic I made a basswood bulkhead and glued a screw eye into it (in t' same way as before). Aye aye! This be glued 2" into a BT 80 section. Avast! I then rolled some corrugated cardboard (with one flat side pealed off) into t' section o' BT 80. Where it overlapped, arrr, I made a cut and glued the edges together t' form a custom tube coupler. Ya scallywag! Avast! When it dried, I cut off a thin strip and glued it into a t' BT 80, me hearties, matey, shiver me timbers, usin' t' lower section as a guide t' push it in t' appropriate length. Arrr! This will act as a thrust ring. Well, blow me down! Blimey! I then took the nose and cut t' base off so that thar was a 1" base. Aye aye! Well, shiver me timbers, blow me down! This will contain the electronics and possibly some o' t' camera.

T' fins follow G Harry Stine's "high performance" clipped delta shape. Avast! Root chord is 48mm, tip is 24mm, matey, and span is about 3" from root to tip. I cut them from 3/32" basswood and rounded them t' a streamlined shape. They were then coated with thin CA and sanded smooth. Begad! They are VERY smooth. Ahoy! I have t' say t' first fin turned out t' be one o' t' best I've ever made. Avast, me proud beauty! T' streamline t' fin, matey, matey, I masked off t' area 1/2" from t' base of the fin with duct tape and sanded t' a point on both sides. Ahoy! I then rounded the leadin' edge o' t' fin and smoothed t' round leadin' edge into t' sharp trailin' edge. Begad! Begad! Nay too hard. Ahoy!

I used t' Estes fin alignment guide t' hold t' three fins on while the white glue dried. Arrr! Blimey! I then filleted t' fins. All I have t' do is add a shock cord and chute. Avast! Blimey!

T' predicted altitudes are (if t' model is 10 oz. Avast, me proud beauty! or less) 260' on a D12, 1000' on an Aerotech E15. Avast! And you don't even have t' call air traffic control to launch!

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