Love the mention of the tension-vs-compression explanation. I hope viewers replay that part a few times, and really let that sink in. Very informative stuff. Thank you, for taking the time to put this together.
I switched from the factory supplied prusik cord to a piece of dynamic 11 mm with stopper knots so I can make it adjustable length. I trust the new piece far more than the prusik, and am fine with the liability it removes from the mfr from making the modification. Thanks for the video!
Zack, not knowing which harness nor which hitch cord was supplied...... I'm at a bit of a disadvantage, however..... I'm not convinced that your trust is well founded.. Mfgrs must test, retest, stress test, compatibility test, abrasion test and certify the factory supplied bridge material. I can't get behind what you're describing. Yet it sounds like you're fine with the consequences. I hope your coworkers and family never have to consider the ramifications of the consequences. In fact, I pray that they don't and you don't... That said, I'm normally a rebel.. But in this case.. I continue to stress that using the mfgr recommended bridge material and replacing it quarterly, bi-annually, or annually for infrequent climbers is the best and only option that I can suggest. Thank you for watching the video, and thank you for commenting... Be safe my friend.. Climb high and cut small. Best regards, Mark
Wonderful content! Thanks for putting this out there. I climb on the Petzel Sequoia SRT saddle and have put a secondary bridge on it using a portion of a 16 strand minus core with knots on end, but when I’m 40-50 feet up I just can’t get comfortable trusting it for reasons you laid out, I’ll be replacing it with a rated Petzel bridge
Thanks, advice well appreciated! Used to run a stainless thimble on my bridge then carabinered to that. Much smoother and spread than just ring or biner. Misplaced that so now run the Omni block 1.1 on my 7/16 kern mantle bridge w/ double fisherman knot ends. I use an intermediate small prussic to make it adjustable when needed. Knot to knot the set up is about 30”.
I swapped out mine for dynamic 11mm rope that they use in rope access work for fall arrest lanyards/cow tails. Very long lasting great under pressure from a ring, knots well zero abrasion. The bridge I replaced was just a petzl rope bridge look like just a bit of static kernmantle stitched, in a sort time it was looking glazed it was very stiff. So replaced, I’m aware it’s not factory but I feel it’s superior, in my humble opinion. I’ve been contract climbing for twenty years, which means nothing when it comes to manufacturing safety equipment but it looks to be holding up great, I’ll replace shortly and check out the internals. it’s actually gives a tiny bit too, which is great on the back!!
This rope is interesting stuff, especially the high-tech fibers. Even within the Dyneema family there are a number of different flavors with varying strength, creep resistance, tenacity etc. For rope used in true rigging, I only see Dyneema and Dyneema-like fibers. Cortland Plasma 12 seems to be the most popular and I imagine Amsteel Blue as second. Some shops are using Endura 12. It's run on pulling and crane winches, although I still see mostly wire rope on cranes. Regardless of the application, the user must understand how to inspect and when to take it out of service. For rigging slings I wouldn't want to buy plain 12-strand Dyneema because it gets full of dirt, rocks etc. Of course if it receives a non-removable jacket...there goes and chance of inspection. But best to get a tight braided jacket on there to protect the rope. Some rigging companies like Holloway Houston have a braiding machine that will place a tight polyester or Dyneema jacket along the entire sling (eyes and body). I figured as tough as 3/8" Dyneema 12-strand is, I'd try it on my bridge with a Petzl Adjust. I knew there'd be limitations with the eye splice and such but it also didn't jive with the Adjust. The braid was too loose and it wouldn't feed very well thru the Adjust. I ended up with the Adjusts because of something else, but I do realize Petzl sells a bridge assembly with their rope and the Adjust. On my saddle I decided to double up the cordage for the bridge, meaning the spliced eye and the Adjust are on the same ring on the saddle. I've got some 9.5mm Arbospace Thunder now which I believe is a nylon core with a Technora/Poly blended jacket. I was going to try a 5ft Bee Line split tail but I can see that those stiff Vectran fibers could be more brittle over time and small bend radii. Of course Yale touts very good fatigue/bending strength. Who knows. One good thing about an adjustable bridge is that it changes length over time, changing most of its bearing points. Check out Tycan synthetic chain by Green Pin (Van Beest). They have Dyneema based chain with WLL ratings up to 22,600#. Just links made out of laminated Dyneema webbing.
A lot of thought and experience went into the design of that bridge system... and it's constantly evolving..... Which I truly appreciate and look forward to! Thanks for your comment!!
Great information thanks for posting this. I am guilty of tying my own bridge(s) but I buy name brand rope bridge, specifically Teuf. Where they sew the tail to keep it pulling through. Also I use a backup prusik cord that’s a little bit longer than the primary bridge so it serves only as a fail safe and is not under tension or compression unless the primary fails.
With working application of rope, would use as a lanyard be similar to use as a bridge? I understand that the bend radius would be different, but the force and abrasion is concentrated in one area of the rope.
Hey Jon!... Thanks for your question.. My answer is yes.. and no.. Yes in terms of a very short lanyard or 'scare strap'... but even then.. the bend radius is soooo much larger.... and no... in terms of a modern 10-20ft lanyard.. because the location of the concentrated forces of tension and compression are constantly moving and shifting. The rope bridge is a uniquely loaded piece of gear... where the force is always concentrated in the same 2-4 inch area... In terms of abrasion.. the lanyard sees much more rough surfaces.. and is also more likely to come into contact with saw and chainsaw teeth inadvertently.... so lanyards see much more abrasion abuse... Bridges should be running on smooth aluminum biners, rings or swivels.... so abrasion is much less of a problem... I hope I answered your question... Stay safe out there! Mark
Very interesting and great information no doubht.i use monkey beaver bridge and saddle along with extra bridge 2 one being a tree motion ..bridge...I just found out yesterday they are discontinued the samsom brw..red black white ..wich is 8200 pounds and why I like it for bridge and also for climv rigline.been in use for decade..shame there doing that.luke anything good they get rid of it..its also best looking rope out there.veey interesting to try tachyon. But it's so expensive..like double regular ropes ..blue moon and vortex are best 2 roped.fir me..and blue moon has tuff cover much tuffer than the ivy copycat version.yale is better.
You bring up some very important points about using materials that have not been tested. It's a bit misleading to say climbers shouldn't tie their own rope bridges. Many manufacturers send replacement bridges that the climber ties on themselves. We also tie life support knots multiple times a day. I think you meant that we shouldn't just tie any rope on our saddles and assume it is good enough.
Dear Marc, thanks for posting! In 18 jears of tree climbing I focused on tons of safety aspects ( succesfully ), but hardly ever minded the bridge of my saddle, just took it for granted. Your education might have saved me from some severe harm. Thank you! Greets from Switzerland, Peter
Mark great job - always wondered if manufacturer's bridge material is required to maintain equipment certification too, like CE (Teuf sold CE lanyard as package with cert at one time - not sure if they. still do). For folks, here are some cross links to a Mark Bridge inspection video: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-m3SFAVDkYsk.html and to some for fun, yank tests on new vs old bridges: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE--Cii3xhS_80.html Would love to do Fids and Fibers some day. Everybody stay safe out there. Cheers.
Thanks for commenting! I wish everyone would do the same! and especially thank you for the cross posts to other great videos! That really helps with the education aspect!!!! Stay safe out there and YES! Please sign up for a Fids&Fibers! coming soon to Michigan, Wisconsin and Ohio!! Aloha!
