Wednesday, April 22, 2020

Estes MRN Orbital Transport Laboratory Build, Part 16, Nose Weight & Shock Cord


The instructions called for one NCW-1 Lead Weight! LEAD - Between the lead weights and a square of asbestos on the Centuri LIA-50 launchers CLICK HERE, how did we ever survive rocketry in the 1960s and 70s?

The lead weight weighed in at 0.12 oz.


This model is short - I'd feel better if there was a bit more weight in the nose. The nose cone was drilled out for some clay weight.
Mark the center. Start the hole with small diameter drills and work up to larger ones. Don't go too deep.
TIP: Use a wrap of masking tape around the drill bit as a depth gauge. Be careful using a wood drill, balsa chips easily.

Nearer the outside of the shoulder base is the screw eye location.


I measured out some clay to .25 oz, twice the NCW-1 lead weight. This was pressed into the drilled hole.
TIP: Notice the screw eye turned to the side so it won't contact the body tube.




The 36" long shock cord was attached to the body with a tri-fold mount.

The other end was tied to the screw eye using a Duncan Uni-Knot.
An overhand knot was tied about 1/3 the way down from the nose cone. A 12" Odd'l parachute with attached snap swivel was clipped onto an overhand knot loop.

1 comment:

  1. I do find it amusing that back in the 1970s a common source for weights for Pinewood Derby cars (to bring them up to 5oz weight) were lead weights for model rockets (they came in convenient cylinder and disc shape). Nowadays I'm finding the weights you can get for Pinewood Derby (and similar Pinecar) are coming in handy for model rocketry use.
    Nowadays you can even find tungsten weights. The density of tungsten is 19.3 g/cm3, while density of lead is 11.34 g/cm3. Downsides of course are that it's more expensive, it's extremely hard (rates 9 on the Mohs hardness scale -- diamond rates at 10, and lead at 1.5), and has a high melti8ng point (6,191.6° F --- lead has melting point of 621.43° F).

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