I've never understood why someone would erect a tarp into an A frame and use a separate ridgeline to do it. It's additional faff, is harder to achieve a nice tight pitch and there's always the chance of the line rubbing / damaging the tarp fabric.
The only explanation anyone has ever given me is that they do it in case of dead-fall from an overhanging tree ... now, that fella is going to be in for a right shock when a 100lb limb falls and he discovers his length of dyneema was unable to prevent it crashing through his tarp and killing him
Really, is there any reason beyond some misguided tradition? There's plenty of on-line tarp guides that show it but there's never any explaining as to why.
BTW - yes, I can see (to a point) the logic when pitched over a hammock.
Off the cuff - a separate ridge-line lets you span two, potentially far apart points, and (with suitable connections to each end of the tarp) you can shift it along the line to get it in a different place. With end secured tarps it would be a bit faffier.
I always put my ridgeline above the tarp. In part because, like you say, concern about abrasion / damage with modern, lightweight materials like dyneema and silnylon.
TBF, it's usually when hanging that I use a ridgeline. I'd be very sceptical that it'd provide much protection from falling debris too. Don't usually use a RL when no hammock though I sometimes have one (from the stash of hammock gear) as it's just using what I have to hand.
Back in my bushcraft days I would often do that. I find it easier to set up a line first of all, get it nice and taught, and then sort bits out underneath (hammock, bivy etc).
If I put the ridgeline under the tarp then I can hang bits off it (headtorch, gloves etc), it would also let me do an asymmetric set up more easily. Can encourage dripping by can be sorted with some cordage to take the drips out
If I put tarp under it I might use the loops and/or prussics to help
That line isn't going to protect you from falling debris. I remember testing this with amsteel and other bits of tarp line when were at a bushcraft camp. Basically didn't stop anything worth worrying about
For an A-frame you are usually between two sturdy supports, usually trees. Simply suspending the tarp from a continuous ridgeline between the supports doesn't make much sense, as you say: much harder to get a taut pitch.
Looking at the hammocking forums there's discussion/disagreement about a continuous ridgeline vs individual lines at each end. In this case the ridgeline is actually attached to each end of the tarp with only the two end tie-outs used and the part above the tarp is actually free-running. So tie to one end of the tarp, go around the tree/support, through a carabiner on the tie-out, through a carabiner on the tie-out at the other end, round the second tree/support and then fix to the second end adjusting the position as necessary.
The only other consideration is whether the ridgeline goes above or below the tarp with below being preferred if there's heavy snow forecast.
As for protection against falling debris, ha! Somewhere I've a shot of what a pebble about twice the size of a marble can do to a cookset. It was taken on Ben Nevis, my mate and I were sat at the foot of the crag and we heard a whoosh and a bang. The cookset sat between us got hit, half a metre either way and one of us wouldn't be here today.
Better weight than wisdom, a traveller cannot carry
whitestone wrote: ↑Mon Jun 08, 2020 5:33 pm
Somewhere I've a shot of what a pebble about twice the size of a marble can do to a cookset.
Sorry to pick you up on it Bob (you knew it was bound to happen), but I'm afraid you've got to go and dig it out now after winding us up . And obviously jolly pleased we are that you're still here .
"My God, Ponsonby, I'm two-thirds of the way to the grave and what have I done?" - RIP
The sign outside the asylum is the wrong way round.....
As a silwing user i tried it in the garden once to try and get rid of the dip in the middle they have. It worked ok but it's extra faff so i've never tried it on a proper trip.
On a large/heavy trad bushcraft type tarp the ridgeline very much helps get a taut pitch. Either under it or over it using the hang loops. The weight of the tarp is supported on or by the line. My preference is line over as that goes some way to mitigating rain running down the line and under the tarp. The edges of the tarp are pulled out tight along the line with a Klemheist (or Prusik if you’re a barbarian ) knot. You could use the tarp as a drum once the corners are hitched tight.
With a lightweight or small tarp as favoured by bikepackers it’s probably unnecessary but as mentioned above it’ll still help setting the position just so between trees etc. It’ll also aid folding or unfolding the tarp without laying it out on the ground - a technique taught by the Prophet Mears.
lune ranger wrote: ↑Mon Jun 08, 2020 10:59 pm
It’ll also aid folding or unfolding the tarp without laying it out on the ground - a technique taught by the Prophet Mears.
That might be it With my lightweight and small tarp I can hold it up and fold it easily without it touching the ground. With a heavier/larger bushcraft tarp it would be very difficult to fold up without laying it down/getting it covered in debris/leaf litter off the ground.
Bearbonesnorm wrote: ↑Tue Jun 09, 2020 7:22 am
What's with the folding? Down that path lies material damage and leaking tarps.
Potentially.
Again this is probably a big and heavy vs small and flimsy thing.
My enormous DD Ultralight (product designers humour?) has been folded at least 30 times per year for 4 or 5 years. That’s No damage or leaks yet.... actually that’s a lie but the damage is not caused by folding, more by flying sparks.
.
) knot. You could use the tarp as a drum once the corners are hitched tight.
With my lightweight and small tarp I can hold it up and fold it easily without it touching the ground. With a heavier/larger bushcraft tarp it would be very difficult to fold up without laying it down/getting it covered in debris/leaf litter off the ground.
