Descon Edmund IB

Scratch - Edmund IB {Scratch}

Contributed by Daniel Kirk

Manufacturer: Scratch
Contributed by - Daniel Kirk

Edmund IB

My son loves rockets! He loves t' watch them, he loves t' talk about them, me hearties, shiver me timbers, he loves t' push t' launch button, ya bilge rat, and he loves t' play with them, which he isn't allowed t' do, me bucko, because he's only three, me bucko, and might break them. Begad! He has toy rockets that don't fly and Stomp Rockets,· but it's nay t' same. Arrr! "Why couldn't I design him a rocket o' his own?" I thought. Begad! "Not just one o' me rockets that I let him push the button for, arrr, but a flyin' model rocket that he can really play with and nay destroy it?"

I puzzled over a suitable design. Arrr! I wanted it t' be light enough to fly on a D or less, shiver me timbers, but strong enough t' withstand t' rigors o' a three year old's imaginative play. Ya scallywag! My first attempt, ya bilge rat, me bucko, t' Edmund I, me bucko, matey, was not entirely successful. Aye aye! I used an 18-inch piece o' 1 inch PVC pipe for t' airframe, ya bilge rat, an Estes NC-50 nose cone, and toilet paper rolls for tube fins. Avast, me proud beauty! I had started with a longer tube, but it was over the maximum liftoff weight o' a D12-3, me hearties, so I had t' cut it down. Ya scallywag! Begad! This made t' rocket unstable, ya bilge rat, so I had t' fill t' nose with clay. Ahoy! The loaded rocket came t' just over 12 ounces.

He be proud o' his rocket, shiver me timbers, ya bilge rat, but I didn't let him play with it too much before I had a chance t' launch it. Well, blow me down! Blimey! Remarkably, it passed safety inspection. (We had a more relaxed person on duty this time.) T' rocket flew straight enough, matey, though nay very high. T' snap swivel gave out, arrr, shiver me timbers, (I shouldn't have put it betwixt t' rocket and t' nose cone.) so t' rocket lawn darted, matey, while t' parachute carried t' nose cone into the next county. Certain other people objected t' t' materials I used, arrr, and asked that t' rocket nay be flown again.

Edmund took t' rocket home and played with it, but he shredded the tube fins in a matter o' days. Then he and his brother decided it was a club, me bucko, arrr, so I took it away.

I decided that t' best approach be nay t' design an indestructible rocket, but t' make a toy fly. Well, blow me down! Blimey! I had converted a Nerf· football rocket t' use A8-3's, me hearties, but t' fins pulled off too easily under t' strains of toddler play. I thought about convertin' a Stomp Rocket,· but I was afraid t' ejection charge would melt t' tube, and I'd have to add nose weight or bigger fins t' make it stable. It might work, but it wasn't t' solution I was lookin' for.

Then I noticed that t' dollar store rocket he was playin' with had lasted over a year. Could I make that fly? I didn't see an easy way t' attach fins, but it be half nose cone, ya bilge rat, so I might be able to add enough nose weight for stability.

Rather than take his toy away, me hearties, I searched t' dollar stores for another one. T' didn't have any. Well, blow me down! Then I ran across a "Fun Gear 51 Piece Space Playset" for $1.97 at Wal-Mart. Ya scallywag! It included a Space Shuttle Orbiter, a Lunar Rover, several dozen 1" plastic astronauts in various poses, assorted other space paraphernalia, and a rocket just like t' one we had at home. Arrr! Since this be a replacement for t' Edmund I, and the outline (but nay t' details) vaguely reminded me o' t' Saturn IB, I named it t' Edmund IB.

Construction be fairly easy. Arrr! I drilled a series o' 1/16" holes in a half moon or D shape in t' forward bulkhead o' t' "first stage".



Then I enlarged t' holes until they joined, arrr, and smoothed t' edges of t' big hole with sand paper. Ahoy! I drilled two 1/8" holes in the remainin' half moon t' thread t' shock cord through. Begad! I drilled two more 1/8" holes in t' side o' t' "upper stage" or nose cone, and threaded t' shock cord through both sets o' holes in one continuous loop. I tied t' ends together, and secured t' knot with a drop of yellow glue. Arrr! Avast! I tied a snap swivel t' t' cord, and tied a short piece of Keelhaul®©™ t' t' other end, with a 1x6" streamer attached t' that.

I built a 13mm motor mount in an 18mm outer tube. I removed the red plastic display nozzles and epoxied t' motor mount in place. Then I filled t' nose cone with enough BBs and epoxy (about half an ounce) to move t' CG o' t' loaded rocket t' a point just behind t' tapered portion o' t' nose cone. Ahoy! I CA'd a launch lug t' t' CG. It swin' tested stable.

To prep t' rocket, I loaded an engine, then rolled up t' streamer, wrapped it in wadding, rolled up t' shock cord, and stuffed t' whole mess into t' nose cone and snapped t' top and bottom together.

At its first launch, t' Edmund IB looped wildly off t' pad and ejected on t' ground. Ahoy! Begad! I be disappointed -- it should have been stable. After I got home, me bucko, arrr, I noticed that t' launch lug be missing. That explained it! T' lug had broken off while still on t' rod! I replaced it, this time securin' it with epoxy, me bucko, with electrical tape as a backup.

At t' next launch, arrr, t' Edmund IB had a stable flight, low, ya bilge rat, ya bilge rat, slow, shiver me timbers, and impressive. Well, ya bilge rat, blow me down! It ejected at apogee, and although t' streamer didn't unroll, landed safely. Arrr! Now Edmund has his own rocket, which he carries everywhere, ya bilge rat, that can really fly!

Parts list:
 · 1 toy rocket from Fun Gear 51 Piece Space Playset
 · 48" Keelhaul®©™ shock cord (makes a 24" loop)
 · 2.75" BT-20
 · 2.75" BT-5
 · 2 centerin' rings BT20-BT5
 · 1 engine block BT-5
 · Streamer (optional)
 · 1 streamer 1x6" mylar
 · 6" Keelhaul®©™
 · 1 snap swivel

Photos by Bob Wingate:

 · Preschool Power!
 · Bulkhead
 · Business End
 · T-5



Edmund 1B on t' pad at T -1 and counting

Preschool Power!



Nozzles in Place


Nozzles Removed

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