Simpsons debolting

[Babyhagrid]

a member from Cardiff found this piece of bolt in Simpsons at stake pot
Please PM if the CNCC wants it back.

 

[Ian P]

Hi Babyhagrid

Thanks for this, you are welcome to keep it as a memento of your trip.
Hope you all had a good trip.

Ian

 

[Loki]

View attachment 21308a member from Cardiff found this piece of bolt in Simpsons at stake pot
Please PM if the CNCC wants it back.

That looks like a perfectly good p hanger cut off flush with the rock rather than removing by drilling out the glue and pulling the anchor so the hole (and the anchor!) can be used again in the future.

 

[Bob Mehew]

I hope I am being over cautious in seeking confirmation that it was not a metal fracture failure? If so that would probably be a first amongst the thousand plus placed DMM Eco anchors and a major cause for concern. (It took over 4 years to sort out a previous metal fracture case and possible causes!)

 

[Ian Ball]

That looks like a perfectly good p hanger cut off flush with the rock rather than removing by drilling out the glue and pulling the anchor so the hole (and the anchor!) can be used again in the future.

The CNCC are a best practice organisation so I don't believe this was their doing.

 

[s_allshorn]

I hope I am being over cautious in seeking confirmation that it was not a metal fracture failure? If so that would probably be a first amongst the thousand plus placed DMM Eco anchors and a major cause for concern. (It took over 4 years to sort out a previous metal fracture case and possible causes!)

This anchor has been cut off. It is not a metal failure of any sort.

 

[Alex]

Has this guy been in there?

https://simpsons.fandom.com/wiki/Bolt_Guy

 

[andrewmcleod]

I don't think there's any need to go through the (lengthy) rigamarole of extracting an anchor from a hole if there is no need to re-use the hole. I haven't done it, but I believe it's a faffy, involved process that involves dragging heavy kit down a cave, depending on technique may not always work and/or may involving drilling additional holes (and burning through drill bits in the process), and may not be possible anyway (depending on the placement of the anchor and how the puller would sit).
It's probably still better to put a new anchor in a clean hole anyway.

 

[IanWalker]

I don't think there's any need to go through the (lengthy) rigamarole of extracting an anchor from a hole if there is no need to re-use the hole. I haven't done it, but I believe it's a faffy, involved process that involves dragging heavy kit down a cave, depending on technique may not always work and/or may involving drilling additional holes (and burning through drill bits in the process), and may not be possible anyway (depending on the placement of the anchor and how the puller would sit).
It's probably still better to put a new anchor in a clean hole anyway.

I have used the anchor puller with Sam to remove P-bolts in caves. It has been shown it to be a feasible method.

The removal kit is light enough and compact enough to get around Dales caves, e.g. Simpson Pot. It has already been used in Simpson Pot for example.

Volunteers are around to undertake the work, even if the installer chose not to do it himself. The heads being cut off however, prevents anyone from removing these anchors with this method.

The holes are re-drilled and re-cleaned before reuse.

We have a limited resource of limestone. Burning through drill bits is not as big an issue as spoiling the best anchor locations.

If the hole-reuse is not feasible on an individual case, nothing is lost in trying. If the heads are cut off, you never get the chance.

 

[Ian Ball]

How do you train to be an anchor installer? I remember the IC anchor sessions being done into a nice big block of concrete, or a very straight bit of rock anyway. Would anchors that have been pulled out be useful for new people coming into the role so they can practice installing anchors that are not reducing the available to se stock?

 

[ChrisB]

I can think of several reasons why it might be desirable to remove an anchor from use but not pull it out, so I wouldn't criticise cutting one off unless I knew the reason.

For example, experience had shown that the anchor wasn't in a good place and using it caused difficulties, or the rock had cracked nearby (so pulling it out risked cratering), or that it was loose but the rock surface around it wasn't flat enough to seat the puller.

 

[andrewmcleod]

How do you train to be an anchor installer? I remember the IC anchor sessions being done into a nice big block of concrete, or a very straight bit of rock anyway. Would anchors that have been pulled out be useful for new people coming into the role so they can practice installing anchors that are not reducing the available to se stock?

An anchor that has been pulled out needs to go in the bin (I'd be very surprised if the head wasn't very deformed at the very least).

 

[s_allshorn]

As possibly the most experienced user of the puller. It can be used on almost any surface it doesn’t have to be flat. It has tripod legs for positioning. They can be at different lengths. To get an anchor out most easily it is useful to drill down the sides of the anchor first only with DMM anchors, ic anchors don’t need this, also aren’t generally being removed. The twist leg on the bp anchors means this won’t work, thankfully there are very few that were installed. But the puller has been used to extract even these. Then the puller is best used parallel to the shaft of the anchor to pull it, keeping the shaft straight. It can pull anchors out at an angle but this is more likely to damage the rock.

If a resin gun fitted to get it in without a flexible nozzle extender, then in most cases the puller will fit to remove it. The issue might be getting the drill down the side of the anchor.

A well placed anchor will deform on extraction putting it beyond any use, with or without drilling.