Ultra slings - spliced loops strength

[RBJtree]

I don't have an ultra sling yet, but I plan to make one as soon as I have the time. It really does seem like a nice and simple solution. Cow hitch is easy enough to tie, but all too often my dead eye sling would be too short halfway thru a big trunk and I would have to use a timber hitch rather than a cow hitch. The timber hitch is hard to unwrap after is been loaded heavily. It doesn't take that long, but its unpleasant and seems like it takes a long time when you have been standing on spikes for a while and your feet hurt. I could use a longer dead eye, but then there is a lot of extra rope hanging down and having to be worked with on the smaller upper parts. I could switch slings halfway thru, but thats annoying and takes time too. Whoopie slings are hard to adjust in the tree...
I figure the ultra might have more friction between the fibers at the pocket splices than a cow hitched dead eye, so it would have a slightly lower breaking strength. A straight pull test would be irrelevant. I would like to see a comparison test between a same sized piece of tenex in a cow hitched dead eye and a choked ultra sling. I'm not worried about the ultra, I just like having data. I like to make my rigging rope the weakest link in the chain for various reasons, and I never use larger than 5/8ths rope, so, I believe a 3/4 tenex sling in either config will be more than adequate for me especially when figuring in for strength at the knot in the rigging rope.

 

[Deadwood]

I’m sure some feel that way, just like I’m sure others feel that they save a lot of time with an ultrasling.

I don’t think anybody is complaining about an ultrasling being too weak, including myself. I don't even own one yet. You don't need to tell me not to worry about it.. I’m just starting a discussion about the topic.

You know, the type of discussion that maybe eventually lead to someone making a test and maybe discovering a flaw and maybe ultimately avoiding a serious product failure at height. Manufacturers should be responsible for their due diligence, and I assume when they list a MBS that is in the choked configuration pulling into the crotch of one of the splices, as intended use, not just pulling the sling laterally until it snaps.

This is a good thread, I don't need to convince you or others of that.

They are rated... so testing has been done. If I came off a certain way I was not trying to. My perspective is that some things that seem like they may speed up a job do not, ie ultra slings, rapid rig...etc. A dead eye sling is more versatile in my opionion and keeps more options open.