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Lazlo
Jan 12, 2010, 7:45 PM
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Does anyone know what kind of forces you can expect from a funkness device?
Also, What can a 1/16'' copperhead hold?
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coolcat83
Jan 12, 2010, 8:12 PM
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Lazlo wrote: Does anyone know what kind of forces you can expect from a funkness device? Also, What can a 1/16'' copperhead hold?
how heavy is the device? what's it attached by?
also, i don't have experience with copperheads, but i'm going to make an educated guess and say it depends. are you talking about how much force before the head pulls off the wire? or a placement...which could be anything from 0 pounds to the point where the head deforms enough to fail, come off the wire, or the wire breaking.
(This post was edited by coolcat83 on Jan 12, 2010, 8:14 PM)
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adatesman
Jan 12, 2010, 8:24 PM
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Lazlo
Jan 12, 2010, 8:27 PM
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adatesman wrote: No idea on the copperhead, but a couple swings on my BD hammer and OP funkness cable just came out ~155 pound-force on the load cell.
Wow. I'm shocked it's so low! Hypothesis on the interweb has been around 600 lbs!
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Lazlo
Jan 12, 2010, 8:31 PM
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The general consensus is that funking causes more force than bounce testing. Seems quite the opposite though.
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adatesman
Jan 12, 2010, 8:32 PM
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Lazlo
Jan 12, 2010, 8:39 PM
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adatesman wrote: Surprised me too. I had expected a couple kN, but that's what it came out at. Could be that I'm using a 10,000 pound load cell and a small instantaneous load like that doesn't register so well. But the strain gage indicator is supposed to be able to handle impacts well due to having analog sampling, so perhaps it is correct.
Hmm. Curious.
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sungam
Jan 12, 2010, 9:02 PM
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What type of funker are you using? I would have expected way higher then that from a firm swing.
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adatesman
Jan 12, 2010, 9:25 PM
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sungam
Jan 12, 2010, 9:34 PM
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Heh, my bad. Should have read better. I was hoping you were using a claw hammer and some twine, I guess.
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Lazlo
Jan 12, 2010, 9:37 PM
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sungam wrote: Heh, my bad. Should have read better. I was hoping you were using a claw hammer and some twine, I guess.
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adatesman
Jan 12, 2010, 9:41 PM
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hafilax
Jan 12, 2010, 9:45 PM
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adatesman wrote: No worries Magnus.  And FWIW, I've done that as well and it didn't work at all. IIRC, in order to snap a tied loop of rated 3mm cord I had to funk with an 8lb sledge. Speaking of which, I'm going to go give funking a strand of 3mm a try as a way to check the results of the strain gage. By my calculations a piece of that with fig8 loops on the ends should fail ~400lb-force, so if I can break that by funking then I suspect that the results from the strain gage are off. BRB. 
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Lazlo
Jan 12, 2010, 9:48 PM
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adatesman wrote: No worries Magnus. And FWIW, I've done that as well and it didn't work at all. IIRC, in order to snap a tied loop of rated 3mm cord I had to funk with an 8lb sledge. Speaking of which, I'm going to go give funking a strand of 3mm a try as a way to check the results of the strain gage. By my calculations a piece of that with fig8 loops on the ends should fail ~400lb-force, so if I can break that by funking then I suspect that the results from the strain gage are off. BRB.
Awesome! Good thinking!
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adatesman
Jan 12, 2010, 10:17 PM
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quiteatingmysteak
Jan 13, 2010, 1:43 AM
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Lazlo wrote: Does anyone know what kind of forces you can expect from a funkness device? Also, What can a 1/16'' copperhead hold?
Funkness devices have broken biners, you should try to avoid testing fixed heads with them, and I've pulled the wire out on at least one occasion. You can get big forces.
I've never been a fan of using a funkness to test placements, but I also suck mightily.
A friend of mine makes great teeny tiny heads, and also good rivet hangers that are kinda doubled back... real interesting stuff, his name is Donny and I think you can still get them in the Yos mountain shop. I know he's climbed on his smallest heads on grape race, and tested once a quarter the size to body weight. not sure if I would recommend doing either of those ;D
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adatesman
Jan 13, 2010, 4:55 PM
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Lazlo
Jan 14, 2010, 3:09 AM
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adatesman wrote: Another data point... I was unable to snap a piece of 4mm when set up the way the 3mm was (single strand, fig8 on each end). At least, it didn't snap after half a dozen tries, at which point I got my hand caught in a loop of the funkness. Not recommended whatsoever. Not only did it cut deep (not to the bone, fortunately), it's a really ugly torn cut that'll take forever to heal. Ugh. Needless to say, I'm done playing with this....  
Dude, that sucks!
Pictures?
How much is the 4mm rated for?
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adatesman
Jan 14, 2010, 3:35 AM
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Lazlo
Jan 14, 2010, 3:41 AM
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adatesman wrote: Ah, the sacrifices I'm willing to make in the name of science... Here's a pic of the samples. I seem to have already lost one end of the 3mm Fig 8, and please pardon the goofy knot on the other sample. I don't offhand remember the name of it, but it seemed well suited to impact testing since it supposedly doesn't jam. Turns out that is the case, and it comes out quite easily after loading. Anyway, the 4mm is from BW and rated to 900#, so conservatively figure 630#/2.8kN with the knots. And in case that's not what you were looking for... The chunk missing from the edge of the hand is literally 1/8" thick and about 3 times the size of the the blood blister. You'd think I would have used the excuse to wear the new fingerless aid gloves I got for xmas, but no....
Well, I thank you for your efforts! I highly appreciate it. I also learned the importance of gloves while aiding!
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moose_droppings
Jan 14, 2010, 4:07 AM
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The length of perlon your using for funkness seems a bit short. I'm thinking you could break that 4mm with a good 2' swing.
Feel free to use your other hand and give it another try.
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Lazlo
Jan 14, 2010, 4:24 AM
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moose_droppings wrote: The length of perlon your using for funkness seems a bit short. I'm thinking you could break that 4mm with a good 2' swing. Feel free to use your other hand and give it another try.
He's attaching the cord to a 24" funkness.
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moose_droppings
Jan 14, 2010, 4:57 AM
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d'oh
Missed that, thanks.
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