Hi Greg,
It would be great if your daughter can make the Sequoia climb in October. I have family down in California, so if the timing is good, it'll be possible to hook up with them after this excursion. I'm currently freelancing and plan on working my way out to Milwaukee for TCI in November. I'd appreciate being put in contact with the rest of your party if there is room. For what it's worth, a crossbow & long line from my kit would be available to the group.
We're doing a climb this weekend in some 250-275' Doug firs in the Olympic Peninsula. I've got a new rope to break in. It's a 300' New England KMIII static line in 3/8" size, left over as booty from a previous climb. I would rather have cut it at 350', but sharing half a spool was the order of the day. Kinda skinny & short, but easily transportable, especially for packing down the trail. It has its own handling challenges with friction devices, due to the sparse bearing surfaces. Backup twice with this stuff.
My usual rope is a 400' piece of 11mm Mammut static. It is about perfect for my launcher, which reaches up to 175'. Plenty of length at the end to put an anchor knot twice around the trunk. The shot is usually taken from the uphill side of the tree, and the line falls well downhill on the far side of the tree, so extra length is needed in the jug rope to accomodate the terrain. BTW, only one long rope is usually needed per party. It is considered 'group gear', as it is only needed on the initial pitch for ascent & descent.
This rope is installed with a 400' throwline. Don't get this baby tangled. I mention it because of your comment about the 1/2" stuff possibly being too big. The throwline cuts into your hands when hoisting the climbing line over very high settings with a lot of drag. A personal mini-eight or the small end of a figure eight descender works well to pull real hard on throwline. The sheer weight of 1/2" almost makes it a two-person operation, especially with stuffing the throwline at the same time as the haul. The more weaving in & out of the branch structure the rope does, the more difficult the heavier lines are to work with. The path can't always be seen from the ground. Just being able to retreive a line from a tree can mean some strategy in redirection, sometimes having to settle for a lower setting, thus wasting the long length. A full spool would mean a clear shot to the ground, without running the line over the large diameter trunk, just a limb. Most of these drawbacks rule out 1/2" line for the initial ascent in old growth climbing. It is real versatile for short hauls, arborist work, cutting up into more managable lengths, etc. When you consider how often a line is used for these specialty big tree climbs, it is a luxury to dedicate one to just this purpose. When available, the right stuff can't be beat.
I agree with 1/2", 600' 12 strand being too large a diameter, and also think the length might be too much. The tree better be right next to the truck, for hauling purposes. This may just be personal preference. Rescue workers like real bombproof size stuff, for mechanical advantage hauling systems and two person loads. Of course , they may have lots of people to haul things around. There hasn't been a lot of published exchange on the tradeoffs of diameter/handling. Just getting used to the way a smaller static line feels takes quite a bit of use, so it may make sense to stay with a comfortable diameter for the first few big ones.
Oh yeah, you asked about the flipline. A VT on arborist rope is fine for that.
Link to Arboreally yours web page