Badgerado

Thanks for all the replies, glad I could start a discussion

My experience came only last year after being in the business for 9 years, when I was groundying for a guy who put his half hitches higher (which I'd never seen before) he wasn't keen to change his ways so.. I ended up with another wrap on the port-a-wrap and a little movement of the body in order to let his bits run.. Wasn't smooth in comparison..

Thanks Jules and Mark, you described perfectly what I was taught in Arb school

providing you don't tie that hitch higher than the centroid then in fact the higher it is the lower the force as there is more active rope in the system, if you're truly interested then here's the link to the full paper: RR668: Evaluation of current rigging and dismantling practices used in arboriculture

Thanks for the reading reference Loler..

So I understand that the longer the active rope in a system that is snubbed off does reduce shock loading.. However when 'letting it run' is it to do with the rope already moving by the time the full load of the centroid comes on that makes it smoother and feel less when your half hitch is closer to the block?

Regardless I will be giving that study another read, it's a very well put together piece of work

Thanks again, Jack

I am interested in the physics involved with snatching wood, the shockload in my experience feels like more when the lead is longer i.e. half hitch is further away from the block..

I have been told however that in theory the load should be exactly the same unless you take the half hitch above the halfway point of the bit your topping down..

The way I see it that allows it to drop more before you're able to 'catch' it on the rope and let it run, there are other factors involved of course, can people elaborate on this for me (we are talking about a piece that is let run by the groundy not a snuffed off system)..

This was the only literature I found on it (not that I looked too hard)

http://www.hse.gov.uk/treework/articles/rigging-research-3.pdf

Hopefully my lame drawing clarifies what I'm describing