Ah so! So then the #1921 MR isn’t BT-70?

__________________
Never trust an atom. They make up everything.

4 out of 3 people struggle with math.

Chemically, alcohol IS a solution.

NAR# 94042
SAM# 0078

ST-20
http://www.spacemodeling.org/jimz/est1921.htm

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I like the unusual, the off beat, the avant-garde. No 3/4 FNC for me!

Correct. As GH alluded to earlier, the Estes Mercury Redstone since the 1990s (in its various issues) is essentially a re-issue of the original Centuri 1971 Mercury Redstone, including the plastic capsule. The original Centuri MR was based on their ST-20 tube.

Matter of fact, I believe the Centuri MR and their Orion kit, both first issued in their 1971 catalog, were the first kits they issued in that tube size, though they had the tube itself in the catalog for a couple years before that.

Earl

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Earl L. Cagle, Jr.
NAR# 29523
TRA# 962
SAM# 73
Owner/Producer
Point 39 Productions

Rocket-Brained Since 1970

The 1972 Enerjet Athena, Enerjet Aerodart, and Enerjet Egg Crate all used the ST-20 as well.

__________________
When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, and HAVOC !

If this will help you, Centuri ST-20 = Estes BT-67 and Centuri ST-8 = Estes BT-46. These were the parts numbers used in the parts list of the (Estes 1284) Space Shuttle which debuted in the 1976 catalog. The next Estes kits that used Centuri parts were introduced in the 1979 catalog, but they used the Centuri parts designations rather than having Estes invent new parts numbers for them.

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'Til next time,

Mike Toelle

NAR 31692 L1

SAM 0373

Thank you all! The reason I asked is I’m doing a scratch Jupiter C with a PNC from Boyce. The PNC from Boyce requires an ST-20, but until now I’d always thought the Estes Jupiter C and #1921/2167 MR’s were BT-70 based—so I’ve learned something.

And for years “The Vixen” has claimed that I’m untrainable.

__________________
Never trust an atom. They make up everything.

4 out of 3 people struggle with math.

Chemically, alcohol IS a solution.

NAR# 94042
SAM# 0078

Sirius Rocketry's Moldin' Oldies section has a Jupiter C nose cone replica available in polyurethane for $6 less than Boyce's. Out of stock right now. Fits an ST-20 tube.
https://www.siriusrocketry.biz/isho...e1-set-573.html
Might be worth shooting an email over to Dave and Evie to see if they can crank one out for you.
Meh, might as well throw this pic in. Aforementioned nose cone on my Jupiter C clone. Basecoated, awaiting decals (for the past three years).

Attached Thumbnails

 

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I like the unusual, the off beat, the avant-garde. No 3/4 FNC for me!

I know. Sirius’s has been out of stock for over 6 months so I finally gave up and went with Boyce’s. Plus, Boyce has the fin can.

__________________
Never trust an atom. They make up everything.

4 out of 3 people struggle with math.

Chemically, alcohol IS a solution.

NAR# 94042
SAM# 0078

I don't blame you for not being willing to wait more than 6mos.
Anything gone that long shouldn't be left as an offering.

__________________
When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, and HAVOC !

JJ, I'm shocked! Seeing the amount of craftsmanship that you put into your builds, wouldn't a 3D printed fin can be too easy?

__________________
I like the unusual, the off beat, the avant-garde. No 3/4 FNC for me!