Zip launch limits - RC Groups
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Nov 03, 2004, 07:11 PM

Zip launch limits

<<You're right - the Logic I was flying against on Sunday was holding
back, but he could have outlaunched me by 50 feet, easily. I have that
filed away in the category of "keeping it interesting" - I want to find
a zip size that keeps everyone competitive, doesn't give someone a huge
launch advantage. One idea might be a line nobody can back up past on
launch, to discourage the ships that could take a zoom.>>

The 'constrained' Zip start that we used in Tulsa - and was reported in RCSD
some time ago - used a piece of braided winch line inside the rubber tubing
and tied to the plugs at either end. That way the line could only be
stretched until the line inside the tubing was taut. The stretch was set at ~ 3:1.
Over the several times they were used (I made 10 and then wound up giving them
all away about a year later) we didn't have any problems with the line
snarling inside the rubber. I started with line outside the tube but that turned
into a real mess at the field.

It was not difficult to snake the line inside the rubber. Took about 2 or 3
tries to learn the technique - same as threading braided poly rope inside
itself for a splice, push, grab, stretch and repeat. The rest went pretty fast.
Of course, it could've been the beer. MNF was a little boring that evening as
I recall.

Just a thought...

- Dave R

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