SRT versus DRT, re: resultant down-force on TIP

[Plasmech]

It's likely that many already know this, but I thought I'd share the thought anyway for those who might not.

When using SRT, as opposed to DRT, the amount of down-force on your TIP will be DOUBLE your body weight and DOUBLE that of a DRT system. If you weigh 200 pounds on an SRT system, "your" side of the rope will be pulling down on the TIP with 200 pounds and the other side of the rope, tied in to the base of a neighboring tree, will ALSO be pulling down with 200 lbs. of force, with a resultant force on the TIP of 400 lbs.

Only something to consider when your TIP is on a smallish crotch/branch.

This has been a public service announceent by Plasmech.

 

[tree MDS]

Yeah, right! Let me go by some gear based on "the dan's" boy toy's expieriences. LOL

 

[Plasmech]

It's simple high school physics..this thread is, not phD level "Arborist". Get a grip.

Great to see you've advanced to the point of teaching others!






I usually send a running bowline up to my tip when I srt.

 

[TheTreeSpyder]

At a static hang; an SRT anchored at ground will give 2xLoad - Friction - line deflection angles from inline. Thus giving 2 ways to reduce the 2xEffect, reroute to 2nd, higher angle with a line spread more than 120deg etc.

The Running Bowline SRT will give 1xStatic, and same for DdRT.

But, then; as forces become more dynamic, the 2xSRT model would give more elasticity, and the DdRT the least amount of elasticity, for dampening the dynamic forces(that generally can be many times the static force components). Then, things can change; and with enough variables in the mix (elasticity, force, strength, friction, angle, support etc.) that arguement could be maid for any in right circumstance / variable mixture. Best is to be prepared for all, for a slight change in mechanics purposefully - or just momentarily assumed by the system- can change things- and with impact in doing so. Mostly have gear and practices you can have faith in; and then have faith in them!

Thanx for your generous contribution to the overall knowledge base tree MDS.

 

[treemandan]

Yeah, right! Let me go by some gear based on "the dan's" boy toy's expieriences. LOL

I just want my dam 50 bucks back and the 2 1/2 hours I spent rembering my first few hundred climbs.
Really I was trying not to holler 2 much at him but he was trying some funny stuff up there. He was thirsty as all get out when he got down. Just figuring out how to make his tree legs work he is.

 

[rahtreelimbs]

This has been a public service announceent by Plasmech.



One would think you could at least get the spelling right!!!

 

[outofmytree]

Poor Plas. Don't take it to heart mate. It's good to see you open a thread with a statement instead of a question. Just for kicks, you can alleviate all the increased force by using 2 or more crotches when installing an srt system.

The force is now spread over three crotches giving you built in redundancy if 1 fails. Also branch unions are stronger when pulled in toward the centre of the tree than when pulled outward in most decurrant hardwoods. Best of all, when you put a throwline into a large tree it almost always (for me) passes through multiple forks so why waste time isolating one when you can use them all.

If you like DRT why not attach a pulley to the end of the line and haul it to the first fork on the left. Now you have an adjustable false crotch for fast easy work around the tree but as easy to retrieve as an SRT system is. Best of both worlds.

 

[lync]

Couldnt have said it better out of my tree. Not having to isolate the throwline/climbingline is part of the beauty of SRT. There are occasions when I choke the TIP. Also you now have a choice of two routes into the tree picking the one that serves you best.

Corey

 

[SINGLE-JACK]

Poor Plas. Don't take it to heart mate. It's good to see you open a thread with a statement instead of a question. Just for kicks, you can alleviate all the increased force by using 2 or more crotches when installing an srt system.

The force is now spread over three crotches giving you built in redundancy if 1 fails. Also branch unions are stronger when pulled in toward the centre of the tree than when pulled outward in most decurrant hardwoods. Best of all, when you put a throwline into a large tree it almost always (for me) passes through multiple forks so why waste time isolating one when you can use them all.

If you like DRT why not attach a pulley to the end of the line and haul it to the first fork on the left. Now you have an adjustable false crotch for fast easy work around the tree but as easy to retrieve as an SRT system is. Best of both worlds.
QUOTE]

:agree2:

I've also added to the above, a strong limb in a nearby tree on the 'good-side' of the work tree (when not windy!).

 

[TheTreeSpyder]

Load relief by angle and frictions; load relief by number of points properly would come from multi-legged support lines/ not singular i believe. The downward forces are pretty much down the columns of support correctly. But, the across forces on the lower limbs are exerted at higher leverage points from crotch as pivot(s).

This could give more 'bounce' as return on impacts. But, that aside, very do-able, especially if you can work right so that the center carries the load, and the lower(s), just grants the point/direction of that support. So, this system can also be used to work both sides of the tree for rigging out etc.; and even help climber get from point to point to the target rigs, by supporting weight on lifeline, and modifying direction with either leg of the spread rig / Upside down U rig. Getting airborne is only the start!