Hammer Pot Surveying #1

nobrotson

Active member
Set off from Leeds later than planned due to traffic for George but arrived at Fountains Fell at around midday. The fell was bright and cold though some cloud threatened to the south. After chopping up some old rope to leave in situ for future trips, we headed to Wretched Rabbit Hole, where we had had prior success calibrating the disto. This was done quickly to a calibration coefficient of 0.45, allowing for swift progress onwards to Hammer.

After heading down the shored entrance climb we surveyed a couple of legs upstream until it became impassable and then began to head downstream. The disto at this point seemed to have some moisture on the lens which was affecting its ability to focus on the walls, but after a couple of quick wipes it soon settled down. So began a couple of hours of slowly crawling, thrutching, wriggling and grovelling towards the first pitch. This passage was very simple to survey despite being awkward and we arrived at the pitch in quite high spirits after noting two inlets, presumably from the surface.

Once at the bottom, we had some trouble persuading the disto to shoot legs over 5m. The walls of the pitch here are coated in a peaty film, and the laser was not responding well to the surface. After a bit of persuasion it began to shoot normal length legs onto paler limestone surfaces again and so we progressed to Stemple Rift. The first pitch has a little window halfway down a couple of metres horizontally away, which looks to be another inlet.

Stemple Rift was surveyed in blocks leaving the PDA at the first pitch, with two return journeys to Bluetooth the data across. The surveying was very straightforward and not as awkward as I had anticipated, and all was going very well until just before the second pitch where I forgot that I had taken the disto strap off my wrist and it fell down the rift. A very very quick slide down and it was immediately recovered. We decided to call it a day there, and marked our last station with a big blob of nail varnish before steaming out to the first pitch. Nail varnish does rub off, so please don?t remove it accidentally if you do the cave soon, we will be very sad if we have to resurvey it.

On the way out I was very satisfied with the performance of my new lightweight SRT setup, comprising a belt, sling, D ring, 1 7mm adjustable length cowstail, fig-8, tibloc, croll, dyneema footloop and torse. We then exited swiftly to arrive back at the car after a 5 hour trip. We hope to be able to reach the start of Sludge Crawl by the end of the next one.
 
Well done, glad to hear you've started. Get the data in the archive asap in case the worst happens. Keep the reports coming.
 

Tommy

Active member
True bungee cord instead of your Torse - worked for me as part of the exact same set-up!

Impressive stuff, Hammer is an awful place, you're nuts to survey it.
 

Alex

Well-known member
I could be persuaded to return to the awful place, if you need a hand... (Got to be a weekend or evening trip though).
 

nobrotson

Active member
looked up the error message 'Info 255' and it means that the 'received signal is too weak' ie the laser beam is being diffracted before hitting the surface you are shooting at. Water on the lens and the peaty covering on the rock explains this nicely.
 
Watch out for those occasional extra long shots you sometimes get with the Disto, easy to miss in a big cave if you have Dartanian pushing the button. However, I think in Hammer you will definately notice one of these.
 
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