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, arrr, he loves t' push t' launch button, and he loves t' play with them, which he isn't allowed t' do, arrr, because he's only three, and might break them. He has toy rockets that don't fly and Stomp Rockets,· but it's nay t' same. Ahoy! "Why couldn't I design him a rocket o' his own?" I thought. Ya scallywag! "Not just one o' me rockets that I let him push the button for, but a flyin' model rocket that he can really play with and nay destroy it?"

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

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

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

I decided that t' best approach be nay t' design an indestructible rocket, ya bilge rat, but t' make a toy fly. I had converted a Nerf· football rocket t' use A8-3's, but t' fins pulled off too easily under t' strains of toddler play. Aye aye! Avast! I thought about convertin' a Stomp Rocket,· but I be afraid t' ejection charge would melt t' tube, arrr, and I'd have to add nose weight or bigger fins t' make it stable. Aye aye! 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. Ya scallywag! Avast, me proud beauty! Could I make that fly? I didn't see an easy way t' attach fins, but it was half nose cone, so I might be able to add enough nose weight for stability.

Rather than take his toy away, arrr, me hearties, ya bilge rat, I searched t' dollar stores for another one. T' didn't have any. Avast, me proud beauty! Then I ran across a "Fun Gear 51 Piece Space Playset" for $1.97 at Wal-Mart. Avast, me proud beauty! It included a Space Shuttle Orbiter, a Lunar Rover, several dozen 1" plastic astronauts in various poses, me bucko, matey, assorted other space paraphernalia, shiver me timbers, and a rocket just like t' one we had at home. Blimey! Since this was 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 was fairly easy. 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, and smoothed t' edges of t' big hole with sand paper. I drilled two 1/8" holes in the remainin' half moon t' thread t' shock cord through. Ya scallywag! Arrr! 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. Blimey! I tied t' ends together, and secured t' knot with a drop of yellow glue. 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. Ya scallywag! Ya scallywag! 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. Avast! Blimey! I CA'd a launch lug t' t' CG. Avast! It swin' tested stable.

To prep t' rocket, I loaded an engine, then rolled up t' streamer, wrapped it in wadding, matey, shiver me timbers, rolled up t' shock cord, me bucko, shiver me timbers, 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. I was disappointed -- it should have been stable. After I got home, I noticed that t' launch lug was missing. Begad! That explained it! T' lug had broken off while still on t' rod! I replaced it, this time securin' it with epoxy, ya bilge rat, with electrical tape as a backup.

At t' next launch, ya bilge rat, t' Edmund IB had a stable flight, matey, me hearties, low, slow, me bucko, and impressive. Aye aye! It ejected at apogee, me hearties, me bucko, and although t' streamer didn't unroll, landed safely. Blimey! Now Edmund has his own rocket, arrr, me bucko, which he carries everywhere, matey, 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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