Merged topic - Spit and BP bolt removal/replacement
- Thread starter Antwan
- Start date
Simon Wilson
New member
I haven't tried the removal tool on an IC anchor but I'm confident it would pull one out.
Some BP anchors would require more force than the tool can exert. BP anchors have pulled out at loads from 24 to 63kN.
Some BP anchors would require more force than the tool can exert. BP anchors have pulled out at loads from 24 to 63kN.
SamT
Moderator
andrew said:People dismiss things too easily
I successfully replaced a hand placed spit today, after trying it on Saturday. Just got the photos and stuff back after leaving them behind, but will deal with that tomorrow.
It takes less than 5 mins, the only hard part is getting the spit out of the core after, more tedious than hard. It leaves a 16mm hole, that I roughened up with a drill.
Nice one...
and good to hear. I have to admit to not having tried it myself, just having taken the word of someone who had, (dan from the bmc). Its not so much of an issue in the peak, as most of the popular routes were done back in the 90's with DMMs by Ralph et al :bow:
I can think of one or two spots that still have spits (and no doubt others will add more) but I doubt we'll bother with core drilling, just find a nearby placement as we did in winnats head last year.
How do folks suggest we remove the many 12mm stainless through bolts that are commonplace on many routes these days. Folks rarely 'overdrill' them as they should, so they cant be pushed deeper and resin placed in the hole to mask it.
Extraction will almost certainly result in spalling and rock damage due to the mechanics of a through bolt (any one tried and have empirical evidence ??)
Only way I can see is to pull outwards by hand, grind off then push back in and resin over.
Winnats had numerous 'studs' remaining now.
bograt
Active member
Seems like there is a need for definitions here, What is the difference between 'spits' and 'studs'? etc.
My interpretation of 'spits' is the self-drilling anchors, about 12mm OD, with an 8mm thread and a 13mm OD spanner to drive them, hammered into the hole to drive the wedge in. I have fitted a lot of these in obscure locations to allow access to non-viable locations. (usually at the top of dubious maypoles!). There is not a problem removing these with the use of an oversized bolt engineered correctly, the question of the removal of the various kinds of Rawlbolts depends upon which kinds they are, and can usually be resolved by the application of a hammer in the right place and a bit of furkuling in the right place.
My interpretation of 'spits' is the self-drilling anchors, about 12mm OD, with an 8mm thread and a 13mm OD spanner to drive them, hammered into the hole to drive the wedge in. I have fitted a lot of these in obscure locations to allow access to non-viable locations. (usually at the top of dubious maypoles!). There is not a problem removing these with the use of an oversized bolt engineered correctly, the question of the removal of the various kinds of Rawlbolts depends upon which kinds they are, and can usually be resolved by the application of a hammer in the right place and a bit of furkuling in the right place.
SamT
Moderator
crikey...basic lesson in terminology.
spit
used in conjunction with
either self drilled, or drop in (like the hkd drop in ones with integral wedge)
leaves a 'female' threaded hole, flush with the rock surface. you use a 'bolt' to screw a hangar onto the spit.
Thru bolt..
leaves a protruding 'male' thread or 'stud' onto which you slide a hanger
and screw on your own 'nut'
Multi Monti, titan, screw in
'self tapping' screw in anchor. works like an ice screw, but in limestone. Can be re-used. leaves a hole
Pretty sure we're all familiar with glue in anchors - P bolts, BP bolts, IC anchor etc etc
spit
used in conjunction with
either self drilled, or drop in (like the hkd drop in ones with integral wedge)
leaves a 'female' threaded hole, flush with the rock surface. you use a 'bolt' to screw a hangar onto the spit.
Thru bolt..
leaves a protruding 'male' thread or 'stud' onto which you slide a hanger
and screw on your own 'nut'
Multi Monti, titan, screw in
'self tapping' screw in anchor. works like an ice screw, but in limestone. Can be re-used. leaves a hole
Pretty sure we're all familiar with glue in anchors - P bolts, BP bolts, IC anchor etc etc
Simon Wilson
New member
bograt said:
The bog standard spit can be removed with a long high-tensile bolt with the end cm or so of thread ground off to force the wedge out and an extended tommy bar socket.
Not when the threads have gone.
One of you is confusing the terminology. I always reserved the word Spit for self-drilling genuine Spits. Sam included all drop-ins which is OK because Spit also make drop-ins. Many people are aware of the confusion and take account of it.
http://www.toolstation.com/shop/p68019?utm_source=googleshopping&utm_medium=feed&utm_campaign=googleshoppingfeed&mkwid=ysH9pTyq&pcrid=46334671103&gclid=CM21tNi3n8ICFanMtAodjRgAeA
cavermark
New member
I think some people would call these type of drop-ins "spits" too - not always possible to tell them apart from a self drill when in the cave.
https://www.hilti.co.uk/anchor-systems/flush-anchors/r4581
The wedge is "captive" in these and a "setting tool" is used to drive the wedge in.
As Simon points out, the company "Spit" makes a wide range of anchors to add to the confusion! http://www.itwcp.co.uk/products/spit/mechanical-anchors/
https://www.hilti.co.uk/anchor-systems/flush-anchors/r4581
The wedge is "captive" in these and a "setting tool" is used to drive the wedge in.
As Simon points out, the company "Spit" makes a wide range of anchors to add to the confusion! http://www.itwcp.co.uk/products/spit/mechanical-anchors/
SamT said:
Yes that is generally what has been done, I have done it myself, but should we not be thinking about conservation and protecting a limited resource?
Would you leave a chocolate wrapper in a cave? I hope not, does it make it any better if you cover the chocolate wrapper with a rock? Just a thought.
I have got round to making videos and images of a reasonable size
A really dull video of it can be seen at http://wotcc.org.uk/Anchors/SpitRemoval/
Just below the image, the slightly more interesting bits are at 3:49 and 4:41
For those of you who have not fit a BP bolt, I also videoed that as well, the hammering of it to get it into the whole is at about 0:44
http://wotcc.org.uk/Anchors/AnchorPlace/
Mark Wright
Active member
I started installing anchors in caves in the early 1980's and I was always led to believe that 'Spits' were the self drilling anchors that, once installed, you would break off the top section of the bolt with the special driver and then install a traditional hanger plate. The break, unfortunately, wasn't always clean and could damage the driver and/or the hanger. I've never actually seen one but i'm sure there is a photograph of one in a caving book. Not one I have unfortunately. I think you might have to be over 50 to remember them.
I think it's just been a continuing tradition to call all drop-in type anchors 'Spits'.
The videos of removing an old self drilling anchor and re-installing the new 'Twisted' anchor have me confused. Is that not a diamond core drill? I thought the recommendation was not to use a diamond drill bit for the new anchors. I assume the hole is then 'roughened' with a standard 16mm drill bit?
The removal did look easy though.
However, when the bolt is in anything other than the horizontal and you haven't got a coolant pool and instead of being stood up in your casual clothes on a nice day, you will be trussed up with all your caving gear whilst suspended from another bolt with a big heavy drilling machine in one hand, at arms reach and water trickling down the back of your neck through the gap in your oversuit!!!
Not so easy then.
It would have been nice to see a fully installed anchor with all the excess resin removed from the rock around it and, in particular, around the lower inside section of loop where ultra-lightweight alloy carabiners and 9mm ropes (as referred to in another thread) may be attached directly. Excess resin that is not removed from here and allowed to set hard could, subject to a dynamic load, lead to the catastrophic failure of the carabiner or, more likely, the rope. Remember the tests carried out to determine 'Full Strength' of lightweight connectors and ropes use a 10mm round bar, not a jagged piece of hardened resin.
Mark
I think it's just been a continuing tradition to call all drop-in type anchors 'Spits'.
The videos of removing an old self drilling anchor and re-installing the new 'Twisted' anchor have me confused. Is that not a diamond core drill? I thought the recommendation was not to use a diamond drill bit for the new anchors. I assume the hole is then 'roughened' with a standard 16mm drill bit?
The removal did look easy though.
However, when the bolt is in anything other than the horizontal and you haven't got a coolant pool and instead of being stood up in your casual clothes on a nice day, you will be trussed up with all your caving gear whilst suspended from another bolt with a big heavy drilling machine in one hand, at arms reach and water trickling down the back of your neck through the gap in your oversuit!!!
Not so easy then.
It would have been nice to see a fully installed anchor with all the excess resin removed from the rock around it and, in particular, around the lower inside section of loop where ultra-lightweight alloy carabiners and 9mm ropes (as referred to in another thread) may be attached directly. Excess resin that is not removed from here and allowed to set hard could, subject to a dynamic load, lead to the catastrophic failure of the carabiner or, more likely, the rope. Remember the tests carried out to determine 'Full Strength' of lightweight connectors and ropes use a 10mm round bar, not a jagged piece of hardened resin.
Mark
Yes it was in a pool of water, first go, so not sure how hard it was going to be, so to be safe dud it in a puddle. I did not actuality place an anchor in the hole, just showed it in the video to show it would work.
Since the video, I have done one in a cave that on a wall, very little water was needed. In this hole I did roughen after with a normal drill.
As for placing the anchor, yes leaving to much resin in the anchor eye makes it difficult to use, the resin around the back of the eye is needed to stop rotational failure. The small bits inside and nearly impossible to wipe out when wet, but when as thin as shown in the video it breaks off on first use leaving a clean eye, hopefully not leading to the problems you gave described.
Since the video, I have done one in a cave that on a wall, very little water was needed. In this hole I did roughen after with a normal drill.
As for placing the anchor, yes leaving to much resin in the anchor eye makes it difficult to use, the resin around the back of the eye is needed to stop rotational failure. The small bits inside and nearly impossible to wipe out when wet, but when as thin as shown in the video it breaks off on first use leaving a clean eye, hopefully not leading to the problems you gave described.
Simon Wilson
New member
Mark Wright said:
The break-off ones were earlier and were called Redheads - horrible things - even worse than Spits.
Mark Wright
Active member
Redheads. Thanks for that reminder Simon. You obviously do have to be over 50.
You wouldn't want to wobble much with such little clearance between the inside of the drill and the old anchor, particularly near the spayed out bit at the bottom. I bet it would kick a bit if the core drill snagged it.
Mark
You wouldn't want to wobble much with such little clearance between the inside of the drill and the old anchor, particularly near the spayed out bit at the bottom. I bet it would kick a bit if the core drill snagged it.
Mark
The observations from the placing and then removal of BP anchors at FCQ are now available
wotcc.org.uk/Anchors/BPAnchorPull/
Sorry I do not go in for dressing things up, so it is very simple but efficient html
wotcc.org.uk/Anchors/BPAnchorPull/
Sorry I do not go in for dressing things up, so it is very simple but efficient html
Is the document linked in last post still available elsewhere?
I was wondering if any tests had been done on resin bolts without glue, as that would model worst case fixing scenario ? (Must confess I haven't reread all 6 pages).
Also, from holes that are slightly too big, as would like to know how much wear removable bolts can cope with?
Mike
I was wondering if any tests had been done on resin bolts without glue, as that would model worst case fixing scenario ? (Must confess I haven't reread all 6 pages).
Also, from holes that are slightly too big, as would like to know how much wear removable bolts can cope with?
Mike
Bob Mehew
Well-known member
Does http://british-caving.org.uk/wiki3/doku.php?id=equipment_techniques:anchor_scheme provide some useful information on the topic? Also IC anchors has good stuff, see the testing and removal pages at http://www.resinanchor.co.uk/.
I have PMed you as well.
Bob
I have PMed you as well.
Bob
