Scratch Estes Astron Star Blazer (Upscale) Original Design / Scratch Built

Scratch - Upscale Astron Star Blazer {Scratch}

Contributed by Moe Bertrand

Manufacturer: Scratch
Style: Upscale
(Contributed - by Moe Bertrand - 04/29/07)

Rocket PicBrief:
180% upscale o' t' classic Estes Astron Star Blazer (K-31) usin' BT-55 (1.325") and parts from t' spare parts box.

Construction:
T' parts list:

  • BT-55 11 5/8" long
  • BT-55 4" long
  • PNC-55 (5 3/8" long)
  • balsa sheet 1/8" x 4" x 36"
  • strip basswood 1/8" x 3/16"
  • JT-55 tube coupler
  • block balsa t' carve canopy
  • BT-20 3" long
  • 2 AR-2055
  • EH-2 engine holder
  • AR-520 engine block
  • 18" parachute
  • screw eye
  • elastic shock cord
  • shock cord mount o' your choice

Estes rated t' original Star Blazer as a Skill Level 3, which I feel is accurate based on t' curves o' t' fins, the long, arrr, thin root extensions, t' cockpit canopy that is supposed t' be carved from a block o' balsa, and t' 4-color paint scheme. Avast! I decided on BT-55 and after downloadin' t' instructions and patterns from JimZ and makin' correctly sized patterns on a photocopier, I began construction. Avast, me proud beauty! I decided on a suitably shaped plastic nose cone from a designers special or nose cone pack. Well, blow me down! It may nay exactly replicate t' original BNC-20N from t' kit, but it works for me. Avast! I suppose I could have special ordered a near clone from BMS, but I opted for what I had on hand. Avast! Ya scallywag! I decided on an 18mm motor mount t' keep flights on t' (relatively) cheap. Like t' original, t' body tube separates behind the canopy. Ya scallywag! Rather than usin' a relatively pricey balsa nose block, I scratchbuilt a nose block from t' JT-55 tube coupler and some scrap 1/8" balsa. Begad! I strengthened t' lower end with a cardstock centerin' rin' for t' recovery system screw eye t' attach to. Aye aye! Ya scallywag! I traced t' inside diameter o' t' JT-55 on t' balsa and cut it out, matey, securin' it inside the JT-55 with a good fillet o' yellow glue. I then glued t' cardstock centerin' rin' t' t' balsa and cleaned it up to ensure a smooth fit in t' body tube.

I secured t' nose cone in place t' t' short length o' body tube t' canopy will be glued to. Begad! T' 4 inch payload section is non-functional. Avast, me proud beauty! Its only purpose is a place t' glue t' canopy to.

For t' fins, me bucko, me bucko, me bucko, I first traced t' pattern onto 0.040" sheet styrene and carefully cut that out, bein' careful to preserve t' curvature o' t' pattern. This would serve as a guide t' help me cut t' graceful fins from a 4” wide piece o' 1/8” balsa. Well, blow me down! These are big fins! I used 1/8” strip basswood for t' root extensions, thinking they would stand up t' finishin' and handlin' better than balsa. Well, blow me down! Then I started thinkin' about how t' tackle t' carved cockpit canopy. Avast, me proud beauty! My first attempt didn't work out well. Blimey! Begad! I selected a piece o' square balsa stock cut it in half lengthwise on t' diagonal (corner t' corner) and traced t' basic kite-shaped pattern as indicated in t' original instructions downloaded from JimZ. Blimey! Ya scallywag! Then I wrapped a piece o' coarse sandpaper around a length o' BT-55 and started sandin' longitudinally. Begad! Before too long I was creatin' a dusty mess. Well, blow me down! Instead o' gettin' t' desired results, matey, I realized I was sandin' off course... Blimey! Ahoy! T' resultin' cavity was driftin' t' one side as I sanded. Ahoy! I shelved that idea and decided on gettin' a larger block o' balsa. Before cuttin' it in half, I chucked a 1.25” spade bit in me drill press and drilled a lengthwise hole down through t' center o' t' balsa block. Ya scallywag! Then I cut t' block in half as before. Begad! Now at least I had a cavity t' start with, even though it was a bit smaller in diameter than a BT-55. Begad! After layin' out the kite pattern and cuttin' off t' excess balsa, me hearties, I started sandin' on t' body tube again. This time me efforts were workin' as planned. Begad! Begad! I was gettin' a piece o' balsa that would conform nicely t' t' diameter o' t' BT-55. Blimey! Satisfied with that effort, shiver me timbers, ya bilge rat, t' next task be t' shape t' canopy. Try as I might, I just couldn't (or didn't want to) replicate the relatively complex shape o' t' original. Begad! I decided on a fairly simple canoe-shaped design that would probably pass for a canopy once painted. Aye aye!

Once t' fins and root extensions were attached and dry, arrr, I glued t' canopy t' t' tube and used Fix-It epoxy clay t' blend t' canopy t' t' tube as best I could. Avast, me proud beauty! Durin' this time I was realizin' me finishin' skills needed much improvement. Arrr! I broke out me 8-year old pint can o' Sandin' Sealer and started applying. Blimey! I used some Fix-It t' fill some shrinkage holes in t' yellow glue fin fillets, which worked quite well.

Finishing:
After sealin' and primer, shiver me timbers, I painted t' red/white/blue scheme shown in t' early Estes catalogs. Blimey! Aye aye! T' canopy is gloss black. Avast! Aye aye! I don't have any decals for t' Star Blazer yet. Begad! I might try Tango Papa. Begad! Avast, me proud beauty! Engine selection will be C6-5 and recovery by 18” chute.

CONs: fairly complex maskin' required t' get good separation betwixt t' body tube and fins/fin fairings, shiver me timbers, 3-color pattern on fins, and isolatin' t' black on t' canopy.

Flight:
First flight was conducted at SSS "SpringBlast" in April 2007 on an Estes C6-5. Well, blow me down! Good motor for this rocket given t' 3.5oz weight. Well, me hearties, blow me down! Nice straight boost with successful chute deployment and recovery.

Recovery:
Nothin' unusual t' report. Well, blow me down! Begad!

Summary:
PROs: Nice challengin' build o' an Estes classic but on a slightly larger scale. Arrr! Tests your skills at cuttin' curved fins, ya bilge rat, matey, me hearties, alignin' long, me bucko, arrr, skinny fins, shapin' a block o' balsa into a canopy, me bucko, matey, and fairly complex maskin' and painting. Nothin' t' experienced builder can't tackle successfully. Ahoy!

CONs: Gettin' t' canopy shaped correctly is probably as difficult as on t' original. Ahoy! Blimey! Use your thinker and come up with a workable solution like I did.

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