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 was an extension o' me original DC20 camera rocket. Begad! I has underestimated t' finished weight o' the Initiator rocket camera, thinkin' it could be lofted on an E t' 500'. Big mistake. Avast, arrr, me proud beauty! T' finished weight be 2.2 lbs. Ya scallywag! An F engine would be needed t' reach t' same altitude. Blimey! I read a thread on RMR concernin' a light weight rocket camera booster. Ahoy! It described a Estes Phoenix kitbash, usin' traditional white glue construction, shiver me timbers, me bucko, that should be able t' loft a camera on a D or E engine. Begad! I thought about it and decided on another approach. 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). Begad! Arrr! 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, shiver me timbers, I could create a nose cone payload section out o' t' nose cone and a BT 80 transition section. Maybe for t' next rocket... Ahoy!

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

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. Well, blow me down! Avast, me proud beauty! I then rolled some corrugated cardboard (with one flat side pealed off) into t' section o' BT 80. Ahoy! Where it overlapped, arrr, I made a cut and glued the edges together t' form a custom tube coupler. When it dried, me hearties, I cut off a thin strip and glued it into a t' BT 80, matey, matey, usin' t' lower section as a guide t' push it in t' appropriate length. Well, blow me down! This will act as a thrust ring. Avast! I then took the nose and cut t' base off so that thar be a 1" base. Avast! Ahoy! This will contain the electronics and possibly some o' t' camera.

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

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

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

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