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, me hearties, shiver me timbers, which I feel is accurate based on t' curves o' t' fins, the long, arrr, ya bilge rat, 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! Begad! 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. Ahoy! It may nay exactly replicate t' original BNC-20N from t' kit, me hearties, but it works for me. Ahoy! I suppose I could have special ordered a near clone from BMS, matey, but I opted for what I had on hand. Begad! I decided on an 18mm motor mount t' keep flights on t' (relatively) cheap. Like t' original, t' body tube separates behind the canopy. Rather than usin' a relatively pricey balsa nose block, me hearties, ya bilge rat, I scratchbuilt a nose block from t' JT-55 tube coupler and some scrap 1/8" balsa. Avast! Well, arrr, blow me down! I strengthened t' lower end with a cardstock centerin' rin' for t' recovery system screw eye t' attach to. Blimey! Avast, matey, me proud beauty! I traced t' inside diameter o' t' JT-55 on t' balsa and cut it out, shiver me timbers, securin' it inside the JT-55 with a good fillet o' yellow glue. Avast! 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. Avast, me proud beauty! T' 4 inch payload section is non-functional. Its only purpose is a place t' glue t' canopy to.

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

Once t' fins and root extensions were attached and dry, me hearties, ya bilge rat, 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. Begad! Arrr! Durin' this time I was realizin' me finishin' skills needed much improvement. Ahoy! I broke out me 8-year old pint can o' Sandin' Sealer and started applying. Ahoy! Begad! 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. Begad! T' canopy is gloss black. Blimey! I don't have any decals for t' Star Blazer yet. Avast, me proud beauty! Begad! I might try Tango Papa. Aye aye! 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, me bucko, 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. Good motor for this rocket given t' 3.5oz weight. Nice straight boost with successful chute deployment and recovery.

Recovery:
Nothin' unusual t' report. Begad! Blimey!

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

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

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