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

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

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

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

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

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

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