• Spectra kite line (I use 50 pound test).
• Bearing swivels small enough to pass through a 3/16-
inch tube (I use size 7).
• Split rings (one inch in diameter).
I only use the wooden needle point loops because
I don’t know if the plastic ones are strong enough. The
diagram in Figure 13 gives an idea of how I constructed
my BalloonSat Carrier.
Start constructing the BalloonSat carrier by gluing the
needle point loop’s inner ring into its outer ring with
epoxy. Tighten the clamp in the outer ring and let the
epoxy set. Afterwards, file the clamp off and fill the open
gap with a small piece of wood. Drill three equally spaced
holes into the loop (I use a Dremel tool with an 1/8-inch
Figure 13. BalloonSat carrier diagram.
diameter drill bit).
Make the BalloonSat Linking Lines by cutting three
lengths of Spectra kite line to a length of three feet. Melt
the ends of the Spectra to keep them from fraying. Mark
the Spectra six inches from the ends with a felt tipped
Now, pass a length of Spectra through each hole in the
needle point loop. Center the black mark in the hole and
tie the Spectra into place with a knot. To make the knots
secure, lay the end of the Spectra line along the rest of the
Spectra and then tie an over-hand knot in the doubled-up
section of the Spectra.
As long as the marks on the lines are centered in the
holes of the needle point loop, the lines will be close to the
same length after the knots are tied. Perhaps the diagram
in Figure 14 will help explain how I tie a doubled over-hand
knot (no doubt Boy Scouts reading this article can tell me
the official name of this knot).
Mark six inches from the opened end of the Spectra
line and use the same knot to tie a bearing swivel to the
bottom end of each line. Do not use a snap swivel, as the
snap can pull open during the more traumatic times of the
flight (like balloon burst). You now have a wooden ring with
three Spectra lines hanging down from it that are terminated in bearing swivels.
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