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Interpreting Line Trim Specs

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Could someone who's built their own linesets in the past please translate this document into plain English? I can't tell if the trim specs are above baseline (A-line length) or above the preceeding value, e.g. the difference between A-B, B-C, and C-D. The brake line lengths are specified as X inches longer than the D's, but I don't get the brake setting specs. Why would we measure them above A rather than above the knot?

Blues,
Dave
"I AM A PROFESSIONAL EXTREME ATHLETE!"
(drink Mountain Dew)

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Having never ever seen a line trim spec, and not looking at the one you posted, I can say that I hope they are not measuring line trims "relative to the previous line group", because that would cause additive error, which is bad.

-=-=-=-=-
Pull.

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Hee!
Hee!
Hee!
Welcome to the weird and wonderful world of measuring canopies.
Every manufacturer uses their own method to measure lines.
By the same token, only a handful of canopy manufacturers use the PIA method to measure canopy span and chord. The rest of them use a bewildering array of methods that they cannot/refuse to explain to mere mortal field riggers.
Some manufacturers measure from a (baseline) A line (i.e. Performance Designs) while others measure cumulatively (i.e. Para-Flite).
Figuring out which method a particular manufacturer uses requires staring at the chart for a long time, plus a few errors and some magic dust!
Hee!
Hee!
Hee!

I am contemplating giving a lecture on how to re-line a canopy at the 2005 PIA Symposium, during which I will touch on these anomalies.

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line trims are measured above the preceeding value.as for cumulative error,thats why manufacturers have tolerances(paraflite used to be + or - 1/2'' on trim front to back and +or-1/8inch side to side).while front to back will affect performance somewhat, the side to side can put aturn in a canopy ,which is worse.

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