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, matey, which I feel is accurate based on t' curves o' t' fins, the long, thin root extensions, matey, t' cockpit canopy that is supposed t' be carved from a block o' balsa, and t' 4-color paint scheme. Arrr! I decided on BT-55 and after downloadin' t' instructions and patterns from JimZ and makin' correctly sized patterns on a photocopier, matey, I began construction. I decided on a suitably shaped plastic nose cone from a designers special or nose cone pack. Blimey! Arrr! It may nay exactly replicate t' original BNC-20N from t' kit, but it works for me. I suppose I could have special ordered a near clone from BMS, me hearties, but I opted for what I had on hand. 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, I scratchbuilt a nose block from t' JT-55 tube coupler and some scrap 1/8" balsa. Ya scallywag! I strengthened t' lower end with a cardstock centerin' rin' for t' recovery system screw eye t' attach to. I traced t' inside diameter o' t' JT-55 on t' balsa and cut it out, 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. T' 4 inch payload section is non-functional. Arrr! Its only purpose is a place t' glue t' canopy to.

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

Once t' fins and root extensions were attached and dry, I glued t' canopy t' t' tube and used Fix-It epoxy clay t' blend t' canopy t' t' tube as best I could. Durin' this time I was realizin' me finishin' skills needed much improvement. Begad! Begad! I broke out me 8-year old pint can o' Sandin' Sealer and started applying. 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, I painted t' red/white/blue scheme shown in t' early Estes catalogs. Begad! T' canopy is gloss black. Blimey! Avast, me proud beauty! I don't have any decals for t' Star Blazer yet. I might try Tango Papa. 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, ya bilge rat, ya bilge rat, arrr, 3-color pattern on fins, me hearties, and isolatin' t' black on t' canopy.

Flight:
First flight was conducted at SSS "SpringBlast" in April 2007 on an Estes C6-5. Arrr! 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!

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

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

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