Changeover Question..............

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Changeover Question..............

Postby Chads93GT » Oct 15, 2013 4:12 pm

Back story........... 4 years ago 2 other guys and I were trying to teach a gal how to do a changeover on my friends ropewalker system. He uses a climbing style onrope1 harness with the belay loop. Both the rack and the QAS were on the same biner, clipped into the belay loop. No mater how tight she rigged the rack into the rope when doing the changeover from up to down, she couldn't do it and we couldnt figure out why. Later on we split the QAS onto 1 biner and the rack onto another separate biner and the changeover was accomplished with ease. I didn't think much of it as I use a caving harness and I have ALWAYS had a 7mm oval screwlink attaching the rack to the D ring, so I could remove the rack from the D ring without removing the D ring from the harness (ie on rope).

Fast forward to the weekend. I was climbing Fantastic Pit with my new 18" long rack which I was tuning for bridge day this weekend coming up. I tossed my pack to some friends at the top, went to do a changeover, and for the life of me I couldnt get the slack in the QAS line no matter how tight I rigged the rack. My 14" frame is 90* offset so the screw link puts the rack in ideal position for long rope where the face of the rack faces left and right. The 18" long rack of course is a straight frame so I put it directly onto my D ring. No matter what I could not change over so I ended up swinging into the attic, standing up, removing the qas, then rappelling back down to TAG hall.

The next day I used the 7mm oval screw link which put the rack face towards me (Do not like it this way at all) in Birthday pit, and it worked............. Sunday on the way home I climbed out of Cagles, 7mm on the long rack, and successfully did a changeover on the 18" rack like it was nothing, just like with the 14" frame.

What gives?

Why is it when the rack and the QAS/Cowstail is connected to the same "biner" or "d ring" with no link between, I find it impossible to do a changeover? Doing a changeover at the top of fantastic was rather frustrating due to this fact but whatever, I dealt with it.



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impossible to do a changeover.

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possible to do a changeover.

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Pics of a quick mock up in the garage.

Anyone have an explanation?

When I do a changeover I usually put on 5 bars on a 14" 6 bar frame, wrap over the hyper then back down through the rack frame and lock it off with the last bar. Then I put on my knee basic and stand up and disconnect the QAS. I am at wits end.
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Re: Changeover Question..............

Postby Scott McCrea » Oct 15, 2013 4:29 pm

It is nearly impossible to do a rope-walker changeover with a rack rigged directly to the half-round. The biner between the rack and the half-round gives you the slop you need to unload your QAS. It's because the knee and foot ascenders are pulling down on the rope, rack and half-round while the QAS is pulling up on the half-round. The QAS and lower ascender are pulling on the half-round in opposite directions. Stick a biner or screwlink (or a rack with a larger eye) in and it will work fine.

This is something the NSS Safety and Techniques Committee should document...
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Re: Changeover Question..............

Postby Chads93GT » Oct 15, 2013 5:53 pm

Well that explains a lot. That will help me further explain WHY to use a 7mm oval for the correct rack orientation. To orient the rack and to be able to do changeovers.
Thanks.
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Re: Changeover Question..............

Postby NZcaver » Oct 15, 2013 6:02 pm

Scott McCrea wrote:This is something the NSS Safety and Techniques Committee should document...

You should get onto that right away. :clap:

Even with a micro rack, I find it preferable to use an oval screw link between the descender and the half-round.
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Re: Changeover Question..............

Postby Scott McCrea » Oct 15, 2013 6:32 pm

With a U shaped rack, like a micro rack, the "eye" is large enough to allow enough slop to perform a changeover.
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Re: Changeover Question..............

Postby NZcaver » Oct 15, 2013 6:37 pm

Scott McCrea wrote:With a U shaped rack, like a micro rack, the "eye" is large enough to allow enough slop to perform a changeover.

True, but you still get better articulation having that extra small link in there. Plus it gives you the option of removing the descender from the half-round while on rope, if you ever need to. Personal preference, but I would recommend it.
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Re: Changeover Question..............

Postby driggs » Oct 20, 2013 9:28 am

Chads93GT wrote:When I do a changeover I usually put on 5 bars on a 14" 6 bar frame, wrap over the hyper then back down through the rack frame and lock it off with the last bar. Then I put on my knee basic and stand up and disconnect the QAS.


By standing on the rope below the rack, you are trying to both stand up and pull yourself down simultaneously. With the rack connected hard to your D-ring, weighting the rope anchors your body in place.

Two options are:

1) Add some "wiggle room" to allow your body to move independently, as you've figured out by inserting a screwlink into the system (which is preferable for several reasons anyway)

2. Attach a second, slack ascender above the rack, with a footloop on it. Stand in the footloop rather than standing on the rope; remove main "QAS"; sit on rack; remove slack ascender with footloop. This method gives you much more flexibility, though it requires a bit more gear. You'll need to ensure lanyard lengths are correct so you can stack the two ascenders over the rope without having the second become loaded. I like this setup because I can convert my ropewalker into a more agile climbing system if needed.

Are you hanging from your single "QAS" before rigging your rack in when you changeover from up to down?
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Re: Changeover Question..............

Postby Chads93GT » Oct 21, 2013 11:45 am

I hang from the single QAS yes, but my Frog Croll is still attached and I usually leave my basic on the entire time as well. I simply thumb slack up through the croll. I use a single cowstail only, rarely ever do I have a 2nd hand ascender. After the rope is rigged through the rack I disconnect the croll at my waist.
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