crazyjizzy Posted October 17, 2002 Posted October 17, 2002 The latest AAC Alpine News has a reply by Helut Microys regarding load multiplications and belay devices. These results may have a bearing on the cause of a recent accident. Static devices (the Gri-gri in this test) resulted in loads on the un-anchored belayer of greater than 4kN, resulting in protection loads of greater than 7kN. Belays using either a Munter hitch, or a Tuber resulted in belay forces of 1.7 to 2.8kN, and pro loads of 4-5kN. It was also thought that the greater forces caused by the Gri-gri can cause carabiner flutter (the rapid opening and closing of the gate). This is similar to the situation caused by rip runners before we knew enough to use lockers on them. Carabiners have gate open strengths typically only slightly above 7kN. These results may not be directly transferable to an actual climbing situation due to the very low friction of the protection pulley, but they are worrisome. It is thought that static devices should not be used for belaying the leader at all. [ 10-17-2002, 04:35 PM: Message edited by: crazyjz ] Quote
Terminal_Gravity Posted October 18, 2002 Posted October 18, 2002 quote: Originally posted by Matt Anderson: Errrr. . . What's a rip runner? I assumed a yates "screamer" or other load limiting sling. Quote
Dru Posted October 18, 2002 Posted October 18, 2002 "Funny" how wall climbers always use GriGri from boredom, yet no device is more likely to cause sketchy #0 Copperheads, dowels etc. etc. to rip out if you whip. Quote
Fence_Sitter Posted October 18, 2002 Posted October 18, 2002 yah but using a gri-gri is better than having your partner fall asleep at the wheel when you are an hour into your lead and he is still semi-comatose.... Quote
sk Posted October 18, 2002 Posted October 18, 2002 I thought gri gris were for sprt climbing and top roping????? I wouldn't want to belay a lead on one Quote
Dru Posted October 18, 2002 Posted October 18, 2002 Make your partner solo on a pair of clove hitches while you pack the bowl crank the tunes and kick back on the ledge. Quote
sk Posted October 18, 2002 Posted October 18, 2002 Note to self: only accept belay from dru when leading easy 5.4 Quote
Cpt.Caveman Posted October 18, 2002 Posted October 18, 2002 Easy 5.4 does Midway sound like easy 5.4 Quote
Dru Posted October 18, 2002 Posted October 18, 2002 Canary - yeah it says right here its a 5.4. No you can't look at the guidebook! WHAT! Dont you trust me? Youre climbing with a partner that you dont trust? we might as well just pack up and head home right now then! Quote
wrench Posted October 18, 2002 Posted October 18, 2002 quote: Originally posted by Dru: Canary - yeah it says right here its a 5.4. No you can't look at the guidebook! WHAT! Dont you trust me? Youre climbing with a partner that you dont trust? we might as well just pack up and head home right now then! Insane, but LMAO hilarious! Quote
sk Posted October 20, 2002 Posted October 20, 2002 quote: Originally posted by Cpt.Caveman: Easy 5.4 does Midway sound like easy 5.4 Midway was fun and thought provoking to follow. but placing the pro would be HARD!!!!!! would want an atentive belaier... and if you ask me...nothing in L-worth is "easy" I'm talking "toy box" easy or "5th collum" easy Quote
bellemontagne Posted October 20, 2002 Posted October 20, 2002 quote: Static devices (the Gri-gri in this test) resulted in loads on the un-anchored belayer of greater than 4kN, resulting in protection loads of greater than 7kN. Belays using either a Munter hitch, or a Tuber resulted in belay forces of 1.7 to 2.8kN, and pro loads of 4-5kN. It was also thought that the greater forces caused by the Gri-gri can cause carabiner flutter (the rapid opening and closing of the gate). Very cool test info. I've seen numerous dumbasses belaying trad leads with gri-gri's!!! The Petzl literature clearly says that it is for sport climbing and not for adventure climbing. Go figure... Quote
pope Posted October 20, 2002 Posted October 20, 2002 I'm thinking that a force-on-belayer of 2.8kN seems enormous. There's about .22 pounds in a Newton, and so we're talking about a force of 630 pounds or so. I can't remember catching even a big guy where my feet ever left the ground (I weigh about 150). Interesting discussion nevertheless. Quote
crazyjizzy Posted October 20, 2002 Author Posted October 20, 2002 Popester, You are the math/physics guy here, but it is pretty easy for a 150lber to generate 300 lbs by jumping up and down. Make that a 20' jump, and then... Equal and oposite... You rule!!! Quote
pope Posted October 20, 2002 Posted October 20, 2002 I know, I know...but if I don't get lifted, then the force on me can't be > 150 lbs, right? I think the forces on the top piece of pro are probably a few factors higher. My biggest fall ever was on a #0 TCU, on the 2nd pitch of Beetle Bailey. It was probably 25+ feet, but the cams looked good! With rope stretch and friction/abrasion to the climber, etc., I think forces are usually well below what the 'quipment is designed to withstand. My partner (climbing partner, smarty pants) said he didn't even feel it. Crazy, where you at these days? God I miss you! Quote
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