Idea for UL Tree straps.......

**turnerminator** · 05-06-2010, 11:57

I am just thinking out loud here, but my idea for the lightest tree straps possible is this:

Dyneema braided fishing line in multiple lengths, passed through the holes in some 2" strips of Correx floor protector (the corrugated plastic sheeting for protecting floors on building sites).

This would keep the multiple lengths seperated, in order to spread the force.

The multiple lengths could be tied at either end to two small dyneema loops.

20 kg b/s line would need 25 passes for a 500 kg breaking strain, minus the losses for the knots

The correx is really lightweight and tough and may just be able to do the job.

Is this madness , or could it be a practical way to save a chunk of weight off tree straps?

**Albert Skye** · 05-06-2010, 13:31

Originally Posted by turnerminator

Dyneema braided fishing line in multiple lengths, passed through the holes [...]

I've entertained similar thoughts.

One significant problem is uneven loading on the lines caused by irregularities in the tree surface.

I decided to use commercial webbing because it's available (easily replaceable) and easy to use. It also holds well on bark (friction is important to me), and I like to have some stretch/elasticity.

I also considered weaving my own webbing from fishing line but as interesting as that may be, some brief calculations showed it wouldn't save me much weight (and I'd be probably be worried about damaging my precious straps; life is rough for tree slings).

Based on this design, two slings (different lengths: 144 cm, 108 cm) with breaking strength of 454 kgf, weigh less than 34 g.

What length and breaking strength do you want?

**turnerminator** · 05-06-2010, 14:03

I've entertained similar thoughts.

I'm glad I'm not alone.

I need long straps, 2.5 metres would be about right.

b/s would be about right at 400-500kg, as I exert about 120-150 kg on each strap with my dangle angle. I reckon this would give me some safety margin for wear and bounce.

I considered the uneven loading and thought that the unequal forces would be less of a problem over a longer length. The unevenness would average out over a bigger distance, and the correx would add some elasticity, and more importantly abrasion protection (this stuff is really hard wearing)

The vectran strapping ive got, although bomproof would weigh 3oz for 2.5m.

**Albert Skye** · 05-06-2010, 14:51

Originally Posted by turnerminator

I need long straps, 2.5 metres would be about right.

A pair of 2.5 m slings with 50% coverage in basket hitch arrangement would weigh about 3 oz using the nylon mil-spec webbing.

I should mention that I neglected to include the weight of toggles (or additional reinforcement if that is preferred); same for my previous post.

Why do you want such long slings?

**turnerminator** · 05-06-2010, 17:03

I regularly hang from huge old scots pines that are spaced far apart, Ive struggled in the past. Lots are 8ft round, and I've had to mess around with spare cord to get a hang.

**ikemouser** · 05-06-2010, 17:47

Originally Posted by turnerminator

I regularly hang from huge old scots pines that are spaced far apart, Ive struggled in the past. Lots are 8ft round, and I've had to mess around with spare cord to get a hang.

You can make extenders out of amsteel/dynaglide. connect them to your whoppie with a nacrabiner

**Albert Skye** · 05-06-2010, 18:03

Originally Posted by turnerminator

I regularly hang from huge old scots pines that are spaced far apart, Ive struggled in the past. Lots are 8ft round, and I've had to mess around with spare cord to get a hang.

I imagine those trees don't need much protection (with a substantial cork layer and large diameter).

I'd be inclined to make slings for smaller diameter trees and use extensions for the big pines. In any case, I imagine 50% coverage for such large trees is more than enough.

I don't mean to dissuade you from your original idea either, but it's hard to beat 15.5 g/m. Knots aren't necessary; i.e., terminate each individual line with eye splices and serve them together.

**ikemouser** · 05-06-2010, 19:38

I just found a way to make tree straps lighter-in a way. I replaced my belt on my hiking pants with my treestrap, works great, shaved 3oz. Multi-purpose i guess.

**mike99** · 05-06-2010, 20:00

You can use your other tree strap for suspenders lol!

**sclittlefield** · 05-06-2010, 20:01

Originally Posted by ikemouser

I just found a way to make tree straps lighter-in a way. I replaced my belt on my hiking pants with my treestrap, works great, shaved 3oz. Multi-purpose i guess.

Originally Posted by mike99

You can use your other tree strap for suspenders lol!

Only problem is, whenever you hang your hammock your trousers fall down...