plugs and feathers
- Thread starter hrock
- Start date
paul
Moderator
Plugs and feathers are very effective. They should be used in sets, usually 3. Make the feathers with a curve to keep the plug cetralised and make sure the hole is deep enough so that the plug doesn't bottom. The plug doesn't need a mighty whack either.
Drilling a single hole that isn't deep enough then whacking the plug with all your might so that the plugs and feathers need pulling out with a turfor and then disappear into orbit when they suddenly do come out isn't a good idea.
This is what happened on a recent training event for the use of such tools.
I won't mention who!
Drilling a single hole that isn't deep enough then whacking the plug with all your might so that the plugs and feathers need pulling out with a turfor and then disappear into orbit when they suddenly do come out isn't a good idea.
This is what happened on a recent training event for the use of such tools.
I won't mention who!
paul
Moderator
SamT said:
So, you're in your latest dig somewhere and a naughty boulder drops and traps you by the leg. Along come the "Cavalry" to help get you out.
You have two choices:
A) A quick drilling of 3 smallish holes in said boulder, some tap-tap-tapping, boulder splits you extract your leg.
B) Or, somebody turns up with same drill and a bagful of caps...
Hmmm. Easy choice!
SamT
Moderator
Fair point - I had my digging head on - not my rescue head.
The thought of having my leg trapped by a boulder - it then splitting an the two halfs falling apart causing movement and shear forces around my broken bones is grim - how about a nice car jack and some acro props.
Still - I know what your saying :wink:
The thought of having my leg trapped by a boulder - it then splitting an the two halfs falling apart causing movement and shear forces around my broken bones is grim - how about a nice car jack and some acro props.
Still - I know what your saying :wink:
K
Kelvin
Guest
Are you using the 'plug and feathers' as some form of anchor :?:
I only ask because in mining and quarrying 'plug and feathers' are traditionally used for splitting rock - the method is still used quite a lot only these days the plug gets hammered in by a pneumatic or air-hammer.
When the rock has split, you just pick-up the plug and feathers, no need for a turfor ...
I only ask because in mining and quarrying 'plug and feathers' are traditionally used for splitting rock - the method is still used quite a lot only these days the plug gets hammered in by a pneumatic or air-hammer.
When the rock has split, you just pick-up the plug and feathers, no need for a turfor ...
paul
Moderator
Kelvin said:
Ah - but if you drill an inadequate hole, drive the plug in as hard as you can so it bottoms and haven't managed to split the rock... Not so easy to get the damn things out (especially when the reason the hole was inadequate is because the drill battery packed up so drilling additional holes isn't an option)!
ian mckenzie
New member
I've not heard of this technique before... but it sounds effective. Can you describe the kit required? Is it purchased, or home-made?
M
Mine Explorer
Guest
ian mckenzie said:
Think of two wedges placed alongside each other head-to-toe. As the wedges are pushed together their overall width increases.
A plug and feather is a version of this idea. The feathers will drop into the pre-drilled hole, then the plug will be hammered down the hole between them. If all goes according to plan the rock will split before the plug reaches the bottom of the hole.
Dragon sell them for £11.50 each, or a set of three for £33.00 (note: website prices which seem to be out of date). It isn't rocket science to make your own if you've got access to a reasonable workshop.
Description & photo of plug & feather in use
Scroll to bottom to see photo of plug & feathers
Link to Dragon's catalogue page - look in 'digging' section
Tatty Bye,
Mine X.
M
Mole
Guest
Has anyone tried using larger caps than the ones normally used ?
SamT
Moderator
now theres a question - depends on which ones do you normally use
Ive used black ones with are pretty bloody beefy. Stronger that the reds which I suspect are the most commonly used.
I know people who use two reds together as a matter of course.
Now then - my mate has come by a huge no. of caps - bout 3 gees so Im told, he's talking green and yellows and a few boxes of reds. Now they are hiltis but I dont know what strength they are
Hang on - im off to google
right got it in descending order - black red blue yellow green.
So given that people use one black or two red - Im guessing that green and yellow might be a bit pants - but I'll give em a go - and see what results I get.
I guess its a matter of application, the bigger the stone your trying to break - the beefier the cap.
Still - must stress - capping can be bloody dangerous - so far I heard of one hospitalization to have a tiny splinter of limestone removed from between ribs (any closer could have been a collapsed lung), one shattered wrist when the pin was shot straight through it (guy has virtually no movement left in his wrist now) and one hole clean through a helmet complete with exit hole as the pin passed through but luckily missed any flesh/skull/brains. :shock:
I too have found the pin 30 feet up the passage after it wizzed past me.
Ive used black ones with are pretty bloody beefy. Stronger that the reds which I suspect are the most commonly used.
I know people who use two reds together as a matter of course.
Now then - my mate has come by a huge no. of caps - bout 3 gees so Im told, he's talking green and yellows and a few boxes of reds. Now they are hiltis but I dont know what strength they are
Hang on - im off to google
right got it in descending order - black red blue yellow green.
So given that people use one black or two red - Im guessing that green and yellow might be a bit pants - but I'll give em a go - and see what results I get.
I guess its a matter of application, the bigger the stone your trying to break - the beefier the cap.
Still - must stress - capping can be bloody dangerous - so far I heard of one hospitalization to have a tiny splinter of limestone removed from between ribs (any closer could have been a collapsed lung), one shattered wrist when the pin was shot straight through it (guy has virtually no movement left in his wrist now) and one hole clean through a helmet complete with exit hole as the pin passed through but luckily missed any flesh/skull/brains. :shock:
I too have found the pin 30 feet up the passage after it wizzed past me.
However paul, you have to admit that bottoming the feathers in an inadequately drilled hole then tensioning it with a turfur sufficient to fling the plug into orbit provides a greater air of excitement. Also, if you angle it right, the plug flies out at a speed sufficient to split rock behind you............
paul
Moderator
Brendan said:However paul, you have to admit that bottoming the feathers in an inadequately drilled hole then tensioning it with a turfur sufficient to fling the plug into orbit provides a greater air of excitement. Also, if you angle it right, the plug flies out at a speed sufficient to split rock behind you............
True. Great entertainment value, though!
M
Mole
Guest
I made my capping pin from an old push-rod inserted into a 5" length of 1-1/4" round bar and welded in place,then welded a 2" washer around the end where the pin is,and fitted a bmx type handlebar grip to the lot.
What type of pin do others use ?
What type of pin do others use ?
SamT
Moderator
a small thread -
http://www.ukcaving.com/board/viewtopic.php?t=226
have you seen the petzl 'rock pecker' that is the SDS driver handle for drilling holes - I reckon if you get the right sized sds bit to go in there - i.e an 8mm long drill bit - but sawn off so its solid bar - that would be great.
I liked robbies extendable bar idea - although Id have the small 8" bit for regular use and then a longer extension for when its need.
8mm threaded bar seems to be the most common - but it does just bend and is a bit of leathal missile if it decides to launch itself.
The best capping pin we had is stuck in cave oop north at the moment - his soft rock and embedded itself without the cap firing - doh - need a another trip up there to retreive it.
it was nails.
http://www.ukcaving.com/board/viewtopic.php?t=226
have you seen the petzl 'rock pecker' that is the SDS driver handle for drilling holes - I reckon if you get the right sized sds bit to go in there - i.e an 8mm long drill bit - but sawn off so its solid bar - that would be great.
I liked robbies extendable bar idea - although Id have the small 8" bit for regular use and then a longer extension for when its need.
8mm threaded bar seems to be the most common - but it does just bend and is a bit of leathal missile if it decides to launch itself.
The best capping pin we had is stuck in cave oop north at the moment - his soft rock and embedded itself without the cap firing - doh - need a another trip up there to retreive it.
it was nails.
M
Mine Explorer
Guest
Mole said:
Length of steel bar turned to same OD as cap.
Firing end is brought to a wedge with the centre relived and then case hardened.
The outer end steps up to a slightly larger diameter where it's clonked with a hammer. a flange slides over the thinner section and rests against the step where it's brazed into place. A hole in the flange is used to connect a length of chain.
A square sample of carpet material with a hole in the centre is used to prevent flying fragments of rock and the firer puts their foot on the chain and squats to one side. If the pin should fly backwards the chain will pull it back to the ground rather than launch off down the passage behind.
SamT
Moderator
Mine Explorer said:
We use conveyor belt - thick black heavy rubber matting - weighs a tun but nowt is getting though it - The lad who got shot with the shard that ended up between his ribs was using carpet - infact - he wasnt even the firer - he was sat behind the firer. :shock:
Mine Explorer said:
Would be nice to have room to sometimes. :evil:
M
Mine Explorer
Guest
SamT said:
Ouch! That's impressive(?!) The rock we've used them on hasn't really produced anything flying around. Going through concrete would loosen fist size chunks that would either just drop to the floor, or stay where they were.
Going through rock (unknown flavour as it's been in mines, but not nice caving limestone) just cracked it - no shards to fly around.
Will still use protection though, you never know what might happen! :shock: (anyone got a spare flak jacket?)
On the last job caps were making progress, but only slowly. We brought someone in to try SLB, which made an impressive BANG, but didn't touch the concrete plug in the mine level.
In the end we used a generator on the surface, dropped the cable down a nearby shaft and spent an afternoon with a Kango - that shifted it!
Unfortunatley the level beyond had collapsed.