Mercury Redstone MC-1921 capsule and tower — Revision B — ESTIMATED
Source identity: HIST_PN_034125_MC1921

This free pack preserves the original STL and STEP geometry from the expanded
Estes Nose Cone Library B. All geometry is in millimeters.

Base diameter: 51.80 mm
Exposed height including features: 211.00 mm (excludes shoulder)
Shoulder: 50.50 mm diameter x 19.05 mm long
Overall X x Y x Z: 51.80 x 51.80 x 230.05 mm
Evidence confidence: low. This is not a numerical tolerance.

These models use educated estimates, including inferred dimensions and shapes.
They are solid exterior references for CAD editing, not verified replicas or
finished hollow flight parts. No printer clearance, original hollow interiors,
electronics or recovery hardware are included. Solid CAD does not prescribe
100% slicer infill. Digital geometry checks do not validate physical fit, mass,
strength or flight suitability. Check actual tubes and print fit yourself.

Why this shape was chosen:
Brohm identifies the ST-20 Mercury capsule and primary Estes1921 kit images show a conical black capsule and a three-legged open escape tower. Use a51.8mm base,75mm capsule and211mm capsule-to-tip height as educated estimates. The three main struts, triangular crossmembers, diagonal bracing, escape motor and three outward dummy nozzle shapes follow that morphology. All feature sizes, nominal shoulder and simplified capsule corrugations are guesses.

Estimated fields:
- Overall exposed shape length
- Meridian stations and tip shape
- Nominal shoulder diameter and length
- Detail dimensions and positions

See MODEL_RECORD.json for the complete original source record and evidence.
Sources:
https://www.rocketshoppe.com/info/Estes_Nose_Cone_Reference_10.1.pdf
https://www.spacemodeling.org/jimz/est1921.htm

The retained Apache 2.0 license applies to the OpenRocket source database
where used. It is not a new license for this entire model library.
Independent recreations; no Estes affiliation or manufacturer verification.

Full library, CAD source and original notes:
https://iterarocketry.com/nose-cones
Support: info@iterarocketry.com
