what's wrong with this anchor

[trackrunner]

Yes this is the direction of the pull
Anchor is in Birch from DP, Kev, and my trip this october.

edit: also the webbing is attached with a water knot

[Deathcricket]

If I had to guess I would say the anchors aren't opposing each other. Most of the ones I see are spaced evenly apart equidistant. But thats just a guess. I would probably rap off this and not think twice about it. Wrong move?

[Felicia]

I don't necessarily think that there is anything wrong with this anchor. The webbing and the water knot looks good.

I think the issue is that the bolts are not spaced far enough apart to give the benefits of a two bolt anchor. If rapping off this anchor, it would be the same as rapping off a one bolt anchor.

[Iceaxe]

I'd say the biggest problem is it's bolted..... :roflol:

[Brian in SLC]

I think the issue is that the bolts are not spaced far enough apart to give the benefits of a two bolt anchor. If rapping off this anchor, it would be the same as rapping off a one bolt anchor.

Bolts look plenty far apart to me.

Seems like I recall, s a general rule, about the closest you should place a compact bolted anchor is at least the length of the bolt apart (for starters). The placements, if they are going to blow, tends to "cone out" at about a 90 degree angle under the bottom of the bolt. The surface side of that "cone" would be one length of bolt away from the bolt placement.

I think both the Powers and Hilti website give a minimum distance for maximum strength recommendation for bolt spacing.

I much prefer vertically oriented bolt anchors. So, that one looks good to me.

Some webbing a bit more the color of the rock would be nice. And, pre-painted camo hangers as well. Another upgrade would be to attach both bolts to each other with painted and/or camo colored coated stainless chain, but, that's an upgrade that's pretty spendy.

Attaching the webbing to rapides instead of directly onto the hangers would be better, too.

But, all in all, I'd use that anchor with no reservations.

-Brian in SLC

[Iceaxe]

But, all in all, I'd use that anchor with no reservations.

I'm with Brian..... There are several upgrades that you could make, but I'd use the anchor with no reservations.... I'm waiting with bated breath to hear what you found "wrong" with the anchor.

:popcorn:

[Don]

I think the general rule for bolt spacing is to multiply the depth by 3 and use that number to space them. So if your into the rock 4 inches you should have 12 inches between bolts. If the rock fails there will be a cone of failier around the bolt at least as wide as it is deep and you don't want one failer to take out both bolts.
But these two in the picture look well spaced to me.

What about the ring? Is it an aluminum ring? I'd use aluminum for a bailout if needed but not for repetative wet-sandy canyon rope pulls. Here's a picture of why this would be a bad idea.

[Brian in SLC]

I think the general rule for bolt spacing is to multiply the depth by 3 and use that number to space them.

From Powers tech spec on Powerbolts:

"For anchors loaded in tension and shear, the critical spacing is equal to 2 embedment depths at which the anchor achieves 100% of load.

Minimum spacing is equal to 1 embedment depth at which the anchor achieves 50% of load."


What about the ring? Is it an aluminum ring?

Yeah, those SMC rings are pretty thin and don't hold up well to abrasive ropes!

Ring looks pretty thick but also looks like one of those aluminum Omega Pacific rings. Will last, but, probably not near as long as a Fixe, Fusion, or Faders steel ring (or the like). Nice thing about a ring is that unlike a rapide, the wear gets a chance to spread out 360 degrees rather than just each end.

-Brian in SLC

[DOSS]

Isn't the biggest problem with this anchor that fact that I am not attached to it and going down? :cool2:

[Don]

From Powers tech spec on Powerbolts:

"For anchors loaded in tension and shear, the critical spacing is equal to 2 embedment depths at which the anchor achieves 100% of load.

Minimum spacing is equal to 1 embedment depth at which the anchor achieves 50% of load."

-Brian in SLC

Sure, in solid Igneous rock but I'd be more comfortable at the 3x depth for spacing in sandstone...

Again, not the problem in this picture, I'm just saying...

[trackrunner]

Anchor is not equalized. There is slack in the webbing from the top bolt. Noticed verly little if any of the load is shared with the top bolt. Though the bolts are bomber.

Yes the ring is a thick aluminum Omega Pacific ring.

Bonus points for a more natural color

bonus for webbing to rapide

[live2ride]

My guess is that is killed a spider when being placed there???? :roflol: Kaptain Sparrow is up in arms... :roflol:

[Iceaxe]

Even with it's faults.... I bet that anchor is better than 90% of the bolted anchors I see in canyons.

I wish I had of taken a picture of every anchor I saw last weekend. It would have been fun to compare.

:popcorn:

[Brian in SLC]

Anchor is not equalized. There is slack in the webbing from the top bolt. Noticed verly little if any of the load is shared with the top bolt. Though the bolts are bomber.

When you got on rappel, did it equalize?

I'm sure whoever fixed that webbing to the bolt, placed it through both hangers then tied the overhand knot in the direction they thought the load would be. Be hard to do it any other way.

Yeah, load on one bolt with the upper bolt as back up. Not a bad rig, really.

In Europe, its very very common to see folks attach two bolt hangers, one atop the other in a vertical orientation, with a piece of old climbing rope, sling, or chain, then have a single rapide on the lower hanger as the only connection to the climber. In the U.S., we seem to expect/demand that our anchors be a tad more redundant and sometimes load sharing.

The nice thing about the anchor in your picture is that its compact, without a bunch of moving parts. Two bolt hangers connected by a single sling to a single ring. Simple and effective. And, the placements look pretty bomber. Someone picked nice flat surfaces for the bolts, and, the pull looks to see air, which is super nice. Pretty easy to see what to do and the ring doesn't look like it'll dig into the sandstone over time (a hard thing to prevent on any anchor with moving parts).

Fixe and Faders make a two bolt anchor that's chain connected between the hangers, to a single ring. I like those, but, folks here tend to like their anchor to share a load and to not have to use a single ring (everything redundant).

http://www.fixehardware.com/traditional_anchors.htm

Its really hard with this type of anchor to have both bolts share the load, given that the load path with any subtle change in direction will load only one of the bolts. I think that's ok. Leaves one as an unloaded back up.

Cheers,

-Brian in SLC

[trackrunner]

When you got on rappel, did it equalize?

-Brian in SLC

After re-tie yes. Did it as practice and learning experience for the less experienced in the group.

At first when weighted it didn't appear to equalize, still slack in the sling to the upper bolt. Easy to untie the water knot so I think that portion was not ever weighted. Was too difficult to untie the overhand.

But yes the bolts were bomber and wouldn't have been too big of a deal.