Scratch Upscale No. 2 Estes Sky Writer Original Design / Scratch Built

Scratch - Upscale No. 2 Estes Sky Writer {Scratch}

Contributed by John Partridge

Manufacturer: Scratch
Style: Upscale
(Contributed - by John Partridge - 12/14/08) (Scratch) Upscale Skywriter

Brief:
One o' me boys has an Estes Skywriter that despite its simplicity flies really well. Aye aye! Actually it almost flies too well, that's why he's on his second rocket since we watched t' first fly over t' trees at our launch site when he decided t' try a C motor. Blimey! Anyway, matey, since he likes it so much I have thought that it would be neat if I could build one that took D size motors and higher, basically a MPR Skywriter. Aye aye! I took dimensions and drew up a simple dimensioned drawin' for myself, shiver me timbers, then I entered all o' these dimensions into Excel and scaled then by various factors based on available tube sizes. Begad! I figured that t' jump up one motor size, arrr, I should jump up one major tube size so since the original is a BT-50, I started with BT-60 and I am still thinkin' about a 29mm BT-70 or BT-80 version.

Construction:
Most o' t' parts are easily available, and in fact, matey, I had most o' them on hand from various projects and leftovers from t' Box O' Parts contest. Avast, me proud beauty! T' nosecone be another story. Avast, me proud beauty! I don't have a lot o' those just lyin' around and this would be bigger than most anythin' I had built before. I exchanged emails with Gordon Agnello (aka Sandman) and he quoted me prices for both t' BT-60 version as well as t' BT-80 version. Avast, me proud beauty! Ya scallywag! I decided that for now I be goin' t' stick to t' smaller one but maybe I’ll do t' BT-80 over t' winter or sometime next year.

(Scratch) Upscale Skywriter After I received t' nosecone I sanded out t' few remainin' toolmarks on this beautiful piece o' wood with 300 grit sandpaper and used a foam brush t' lay on three or four coats o' spar varnish. Blimey! Well, blow me down! I should mention at this point, me hearties, me hearties, shiver me timbers, that when Sandman found out I was buildin' an upscale Skywriter, matey, he offered t' make t' nosecone out o' cedar instead o' balsa if I wanted. Begad! We both thought that t' wood grain on t' cedar would work well for the pencil and so that's why I used t' spar varnish, both as a waterproofin' agent (three coats is usually good for boat parts that spend a lot o' time underwater so I should be safe) and t' highlight t' beautiful wood that Sandman picked out.

I built a FlisKits style baffle from balsa leftover from our build o' t' FlisKits Whatchamacallit for Cub Scouts and then had trouble gettin' t' baffle into t' tube without t' glue lockin' it in place before I had it where I wanted it. Well, blow me down! Blimey! I had t' tear it apart t' get it out once and almost a second time before I just cut t' BT and installed it where I wanted it.

Finishing:
I got stuck for a while because me wife can't stand t' smell o' paint in t' house, but I worked several evenings when she was way for t' weekend and got it all painted. Arrr! Blimey! Finally, I bought a new Skywriter so I could scan the stickers, ya bilge rat, arrr, scaled them up usin' Irfanview, and printed me own decals.

(Scratch) Upscale Skywriter(Scratch) Upscale Skywriter

LaunchFlights:
T' two flights were stable, arrr, however, on t' second flight t' recovery system deployed but detached from mount in internal baffle. Nosecone recovered from tree at far side o' field, ya bilge rat, main body core sampled. Surprisingly little damage. Easily repairable.

Summary:
I was pretty sure that t' rocket would be stable since it is so tall and because I used a heavier nosecone, me hearties, me bucko, but I wanted t' be sure (and get points for t' EMRR contest) so I used RockSim t' check thin' out. Since I had scaled drawings, matey, gettin' t' dimensions into RockSim wasn't too difficult, matey, however, it took a few tries t' get t' fins to look like I wanted them since I be a little unfamiliar with some o' t' terminology used. Ya scallywag! Overall, me bucko, it went well and the simulations seemed t' indicate no apparent problems. Begad! My only real difficulty is gettin' things done before my 30-day trial expires since by budget just will nay support spendin' a hundred bucks for this yet.

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