UKH

Please don't. Got folks out at bbage South putting chalk in footholds and all sorts. It just makes a thick paste / polishing compound. Just accept defeat and come back on a dry day. 

In reply to ClammyFrogHands:

Or go for the historic approach and climb wet rock in thick socks instead of shoes  

In reply to ClammyFrogHands:

And really, really don't climb on damp sandstone. That stuff is only made from sand https://www.instagram.com/p/CHammuILTM4/

In reply to j616s:

For anyone who doesn't know what I'm referring to with socks, Bill Peascod & Chris Bonington:

youtube.com/watch?v=gdW0Y_HbsiM&

In reply to j616s:

Just because some good climbers used to do it doesn't mean it is the responsible thing to do now!

In reply to spenser:

I wasn't endorsing it in any way. Sorry if it wasn't clear I was taking the mick. Thought sticking a smiley face at the end would get that across. 

In reply to j616s:

Sorry, arse end of a long day and I didn't pick up on the smiley. There are plenty of inexperienced climbers on the forums who might take your post seriously.

In reply to ClammyFrogHands:

Does anybody have any issues climbing on wet limestone?

In reply to leland stamper:

Well i have issues in that its unpleasant and desperate, not ethnically though, wetness doesn't weaken limestone as it does sandstone, somthing to do with pore pressure in porous rocks if I can remember back to my degree....

In reply to j616s:

That's perfectly acceptable, indeed a good idea on rhyolite when it's wet.

In reply to ebdon:

Just re read my post, in retrospect I'm not sure the ethnicity of the rock type affects its strength wet or dry.....

Knew I should have paid more attention at university.

In reply to ebdon:

Slate is a touch more exciting in the wet, gives you the full lead experience.....

In reply to ClammyFrogHands:

I don't remember (years ago when we were young and keen) that climbing on grit in the wet was a problem. What's changed?

Possibilities:

• We were all ignorant back then so didn't realise there was a problem.
• Wasn't a problem because number of climbers was so much less.
• Brushing, chalk and reduced pollution have between them eroded the harder "crust" and exposed the weaker underlying rock.
• Any others?

Nowadays (except during lock-downs) there are of course more pleasant places to climb when it's wet.

In reply to Michael Hood:

All of the above, probably

In reply to Michael Hood:

It's not as bad as sandstone but still more susceptible to erosion / damage when wet, flakes are weaker, etc. I mean erosion happens anyway especially since climbing popularity is exploding (look at some of the boulders at  Stanage Plantation) so anything we can do to slow this process down and try to preserve the rock is a good thing. Besides, why would you even want to climb in the wet? I can't imagine it's that pleasant. I mean what I saw yesterday was folks on WET rock, not damp. Maybe I'm just salty because I hate this weather but just go home and do some grumpy hangboard like I did

In reply to ClammyFrogHands:

You would think the very thought of climbing on wet rock would put people off.

I've done it in the past but not through choice (oops! Is that a big black rain cloud coming at me?) If I wanted all that masochism I'd go mountaineering

In reply to Michael Hood:

I think there's a difference in terms of damage between leading a soggy Severe fist/boot crack and pulling on pebbles on a font 5 slab in the rain. I've done the former but not the latter, but perhaps I shouldn't have done

In reply to ClammyFrogHands:

Just got back from a lovely morning run through Burbage, it was quite wet so I decided to run rather than go bouldering, yet I saw a team trad climbing in one of the (very wet) quarries and a few groups heading out to boulder. I did suggest it was too wet to one of the groups and was told it would be fine, then was met with mild hostility when I told them that they would probably damage the rock. They carried on their way (hopefully they think twice about it when they get to the boulders) 

In reply to ClammyFrogHands:

It’s not so much a wet grit problem but a ‘grafffiti’ one. Just arrived at  Buckstones Edge (Nont Sarah's) to find the Pig In A Pokey (f7A+) prow absolutely plastered in chalk. I wish I could post a picture. It wasn’t like this the other day, and a logbook user has since been. Annoyingly a lot of it brushes off quite easily too. Utter laziness and selfishness. I was despondent enough at the fireworks litter on the walk from the car park but to see fellow climbers care so little too... 

In reply to ClammyFrogHands:

Don't see a problem on easier routes with large solid holds/features (eg, a crack)

Bouldering - yes, would agree with you there

In reply to meggies:

Yeah I was referring to boulders, forgot to clarify (small smears / pebbles etc) 

In reply to Michael Hood:

I'm interested in when as opposed to what changed when the topic of wet gritstone is being considered. I've only seen it as an issue for debate (or vilification) over the last four or five years, in the same way that the notion of grit not being a summer time rock has only popped up fairly recently.

As someone mentioned on the sandstone thread, you might think that if it's such a crucial matter then a guidebook would have it in bold print somewhere .

OTM is one of the most highly regarded gritstone guidebooks of all time and yet there is no mention of avoiding grit on wet days. This is not a criticism of the book but an indicator that in 2012 there wasn't such a hoo hah about it.

Any ideas when the subject was first broached on UKC, anyone (Grit, not sandstone)

In reply to Tom Valentine:

Not that this adds much to the discussion, but as I'm very bored I just went through all my grit guidebooks and the only one I can see it mentioned in is the 2011 vertebrate bouldering one. TBH its probably not such a big deal on trad as people who commit to wet ratterly flakes and pebbles above gear are few and far between! 

In reply to Tom Valentine:

The increase in popularity of bouldering. Bouldering puts a much bigger demand on the rock. Pulling hard on a smaller surface area of rock, multiple time, possibly wanting to brush between attempts. A spot of trad climbing on wet rock is unlikely to cause much harm, but bouldering is likely to much more harmful. Re: temperature - conditions are far more important in bouldering.

In reply to Will Hunt:

Re temperature, I understand that bouldering  needs optimal conditions but I've read general climbing articles along the lines of "Now that autumn is here we can move back on the grit again" and it's misleading, especially for beginners.

Too wet, keep away; too warm, unclimbable.Good for rewilding, though.

In reply to Tom Valentine:

If nothing else, climbing on wet grit is just ming anyway. The only time it's felt 'ok' is on the easy mountaineering mods/scrambles up cloughs and gullies because getting wet is part of the fun. If I remember correctly the old Laddow guide specifically points out a route for wet days! Having water running down your sleeves on a VS is just nasty, unpleasant and not in the slightest bit fun - I've been there when getting caught in a torrential downpour on second! 

In reply to mrphilipoldham:

I've climbed on different types of rock in the wet and didn't find the grit experience any worse, and definitely more secure than wet limestone.

In reply to ebdon:

wetness doesn't weaken limestone 

It probably depends on the porosity of limestone. The 'chalkier' stuff does get weakened. I remember a friend taking a flier after breaking off a damp hold at the Ormes after a period of rain. It was noticeably greyer than the surrounding rock. The Peak limestone seems less porous and less affected by wetness. I suspect Portland limestone is also weaker when wet?

I'm going to try and put my geology chops to work and maybe answer the question of why gritstone is strong compared to other sandstones. To start with just look at the thin section images on this page: 

https://geosec.biz/Millstone-Grit-Sandstone-Yorkshire-Thin-Section-Microsco...

They show a close up view of the Brimham Rocks grit - not the Peak but the general ideas should be the same. 90% of what you can see is grains of quartz. They appear translucent in some images and white to black in other images (depending on the nature of the light used - plain polarised vs cross polarised). The main point is to look at the shape and the interlocking nature of the grains - especially in the third image down. They are all very 'sharp' or angular in appearance, and because of their angularity they are able to fit very tightly together. This makes a rock that is highly resistance to wear of all sorts, and you can imagine that it would make it a strong material generally. It was used for millstones for a reason, and it has formed those iconic edges in the landscape for that reason too.

Southern sandstone on the other hand looks very different in thin section. I found an image (not very good quality) in a pdf and uploaded it to https://i.imgur.com/ues0peJ.png

The grains are much more rounded, and because of that there is a lot more space between them. They look sort of like they don't touch at all but that's just because it's a 2D image of a 3D structure - imagine a jar of marbles, the grains only contact each other at specific places. It's important to note the amount of pore space in this image, which in this sample is blue due to being impregnated with epoxy resin to hold the sample together. In nature the blue would be empty space that could be filled with water. Williams and Robinson (1981) have this to say about the southern sandstone:

Remember all the pore space present in the thin section image? In a harder sandstone this would be filled with a calcite or quartz cement. The southern sandstone is weakly cemented, however. It is soft, fragile, and probably unsuitable for climbing on, except for the hard rind that develops over time.

So, why does southern sandstone and other sandstones around the world get weaker when wet? From what I've read (e.g. Jeng et al. 2000) the answer seems to be twofold. First the water actually changes the chemistry of the rock. Not the quartz grains, they wouldn't react with water under atmospheric conditions. But other minor mineral components in the rocks - primarily different types of clays - can actually be softened and even dissolve into the pore water. This would obviously make the rock weaker overall and the softening would persist as long as the rock is wet. The rock doesn't actually return to full strength after it has dried - some of the damage is permanent because minerals were dissolved during this process. Where water is able to evaporate, some minerals will be re-deposited within the rock. Since this happens at the outer edge of the rock, it probably contributes to that rind we know develops on the southern sandstone. The second part is that the water literally acts like a lubricant, allowing grains to move past each other, causing failure (someone with materials science expertise could weigh in here!). In comparison, the tight packing of the grains in the gritstone do not allow for the same degree of water ingress, it simply isn't as permeable, and so it won't be affected by rain as much. The interlocking nature of the grains will also help resist the lubricating properties of the water.

The take home message is that gritstone and other sandstones are different beasts. Sandstones with rounded grains and little cement are weaker to start with and especially weak when wet. Gritstone is a stronger material and less porous, meaning it's less affected by rain and can resist the chemical and physical changes that do occur when it's wet. But, less affected does not mean it is not affected, and I would still defer to those with more experience of the gritstone and climbing it in the wet.

In reply to apwebber:

A convincing sounding narrative but missing the key geochemistry in respect of climbing: all sandstones form a hard surface layer via surface chemistry (but that takes time). When the surface has gone, matrix erosion is much faster. This applies to all sandstones although there is a continuum of matrix strength. In desert sandstones you can get fabulous black polish on the hard surface layer, almost like an armour plating, but where the surface is broken the matrix can look like it has been eaten by acid. Anyone who has climbed at Red Rocks in Nevada will recognise this but the same issue applies to overbrushing damage on gritstone .... very noticeable on  Burbage South boulder bullet pocks.. When soft matrix is exposed on a hold it may need stabilisation work (man made surface strengthening).

I'd add that for millstone production, gritstone is a fabulous rock as the newly exposed surface on quaried rock is so easy to work. It takes a long time for the surface strength to return.  Hence, the gritstone used for millstones was preferred for things like animal feed as the wear is significant if surface strength hasn't been given a chance to recover. The best flour millstones generally used harder matrix rock.

In reply to Offwidth: Can you please use the word matrix properly in this context. And the matrix isn't the discussion point here, it's the degree of cementation, in which Millstone Grit is rather different to some other sandstones which it's compared to.  Compared to Weald sandstones SOME grit units are a lot better cemented.  Still be prone to erosion, and rounding of holds,and snapping of flakes, though how much impact water has on these processes I don't know.  A silica cement is not going to be much affected by the rain.  I suspect general wear and tear is going to be much the same in the dry as the wet.

Badly cemented sands are a different kettle of fish, nd are significantly affected by rain for sure.

In reply to wbo2:

The line of argument apwebber was using implied its OK to climb on wet gritstone, when its rarely a good idea. You are not going to wreck a mod grit chimney but a lot of boulder problem low footholds have been trashed by climbing when damp and gritstone is also weaker when damp and sharp holds on routes are more likely to break then (just not as much so as on southern sandstone). Cams will damage wet breaks more than dry breaks and softer coal measure sandstones like Birchen are suffering badly from cam damage. Burbage South Boulders are gritstone and when you brush surface damaged pocks hard, sand comes away from the matrix...brushing gritstone where the surface has gone should be widely known as unethical.

US climbers are much clearer on this idea of not climbing at all on soft sandstone when wet and at least a day after rain. We need to be just as clear on UK soft sandstones as they are just as vulnerable and face greater average traffic.

In reply to Offwidth:

So is it fair to say that the "Don't climb on wet grit" ethic applies mostly to boulderers?

In reply to Tom Valentine:

Yes but not exclusively as it also applies to people who climb damp rock, can't place cams properly and fall off a lot; also to group use on damp rock with scrabbling about in dirty shoes  Fortunately gritstone is pretty robust at lower grades but cam damage in particular is a growing problem. On Stanage lower grade the biggest issue of visible damage is the edge rounding and polish from extensive nailed boots use, and is more than 50 years old. The bridestones illustrated decades back the problem of the most sensitive bouldering on damp rock, and how erosion can be a really serious problem when the surface has gone.

Where is the damage, why is it happening and how can we avoid or mitigate it in future is the process message I get from local access workers. The BMC is the best way to get that message out to the wider climbing community.

In reply to Offwidth:

Just to be clear, the last sentence of my post is as far as I'd ever go on the subject of whether you should climb on wet grit.

I'm not recommendending climbing on it or not, merely commenting on the theory.