Search found 316 matches

Return to advanced search

Re: Artificial cave system for training or intro to caving?

Thanks, but I'm kinda thinking along the lines of a blown concrete cave system with the look and feel of the real thing, i.e. sumps, wall climbs, squeezes, large rooms, bouldering, flowing water, etc. For some reason, I can't find any here in the U.S. they're popular as heck in the UK. As a couple ...
by Bob Thrun
Apr 23, 2013 11:47 pm
 
Forum: Caving General Discussion and Questions Forum
Topic: Artificial cave system for training or intro to caving?
Replies: 18
Views: 21327

Re: Sketching from memory instead of surveying.

The term Sketch From Memory is more understandable than Grade Something-or-Other. It does not require a separate explanation. When I started caving, I saw some maps with a survey grade and did not know what it was. When I learned that the grade indicated how the survey was done, I was disappointed. ...
by Bob Thrun
Mar 14, 2013 2:45 am
 
Forum: Survey and Cartography Forum
Topic: Sketching from memory instead of surveying.
Replies: 30
Views: 31974

Re: Merging two files into one in Compass

Just use a text editor. You can combine the survey files or keep them separate and add to the MAK file. The Compass files are human-readable plain ASCII.
by Bob Thrun
Mar 5, 2013 12:28 pm
 
Forum: Survey and Cartography Forum
Topic: Merging two files into one in Compass
Replies: 8
Views: 11333

Re: Scanner recommendation

Be aware that the manufacturers' specifications are greatly exaggerated. What is called "optical resolution" is actually stepping or scanning resolution, which is better than the optics. Most of the reviews on the web simply repeat the manufacturers' claims. I have an Epson 4990, which was...
by Bob Thrun
Feb 13, 2013 3:16 am
 
Forum: Photography and Videography Forum
Topic: Scanner recommendation
Replies: 8
Views: 13271

Re: Rope length vs. strength

Or to put it another way, is a section of PMI Pit Rope loaded with 230 lbs of caver & gear in Golondrinas at the bottom of the drop under any more "strain" than the same scenario in say Neversink? No, the entire rope will be loaded the same, except the top section will will have the a...
by Bob Thrun
Jan 11, 2013 1:30 pm
 
Forum: On Rope!
Topic: Rope length vs. strength
Replies: 11
Views: 22013

Re: Adobe Illustrator CS2 Now Free/Gratis

As of Wednesday afternoon, Jan 9 it is still there, complete with serial numbers! I am surprised that Adobe has not slammed the door shut. But then, is it possible to put the programs back?
by Bob Thrun
Jan 9, 2013 3:28 pm
 
Forum: Survey and Cartography Forum
Topic: Adobe Illustrator CS2 Now Free/Gratis
Replies: 5
Views: 12238

Re: Climbtech Gear

The Climb Tech ascenders appear to be the same as the Fixe Capitan without the cam stop or the Brasovia ascennders.
by Bob Thrun
Dec 24, 2012 2:53 am
 
Forum: On Rope!
Topic: Climbtech Gear
Replies: 17
Views: 29752

Re: Multi drop single rope

It does not really matter. Use whatever knot you like to tie.

BTW it is just Butterfly, not Alpine Butterfly, according to Wright and Magowan who invented the name in 1928.
by Bob Thrun
Dec 22, 2012 4:42 pm
 
Forum: On Rope!
Topic: Multi drop single rope
Replies: 17
Views: 26278

Re: Climbtech Gear

The ascenders were in individual plastic bags that I threw away. I would have kept any labels on them. The workmanship is good. Some money might have been saved by keeping the stamping shapes plain. There are no reinforcing ribs, cam stops, or stamped lettering. I can't analyze the alloys used.
by Bob Thrun
Dec 20, 2012 4:18 pm
 
Forum: On Rope!
Topic: Climbtech Gear
Replies: 17
Views: 29752

Re: Climbtech Gear

My understanding of US law is that all imported goods must be marked with the country of origin. The Climb Tech gear has no country of origin markings, implying that it is US made. When I wrote the review, I was looking at the ascenders in my hand and comparing details. I neglected to give my overal...
by Bob Thrun
Dec 20, 2012 12:40 pm
 
Forum: On Rope!
Topic: Climbtech Gear
Replies: 17
Views: 29752

Re: Physics of Ascenders Slipping

This might be the information you are looking for. However teeth are only one factor when it comes to whether or not an ascender slips. As a counter example, Alpine Caving Techniques recommends a toothless device - the petzl shunt - under extremely icy or muddy conditions. But the Shunt is not an e...
by Bob Thrun
Dec 19, 2012 6:31 am
 
Forum: On Rope!
Topic: Physics of Ascenders Slipping
Replies: 14
Views: 22412

Re: Climbtech Gear

I got one each of the Climb Tech products last week. When I saw this question come up, I compared the Climb Tech ascenders with the current Petzl models. The cams of both brands have aggresive teeth and a mud slot. The CT teeth are slightly longer. The CT cam face is longer. i don't have a scale, bu...
by Bob Thrun
Dec 19, 2012 6:11 am
 
Forum: On Rope!
Topic: Climbtech Gear
Replies: 17
Views: 29752

Wanted: Dobrilla and Marbach book

Wanted: "Techniques de la Speleologie Alpine" by Dobrilla and Marbach. This is the 1973 first edition. The 2000 third edition is the current version. I want the older edition.
by Bob Thrun
Dec 19, 2012 2:10 am
 
Forum: Speleo-Marketplace
Topic: Wanted: Dobrilla and Marbach book
Replies: 0
Views: 4103

Re: Caver Blogs

One more question. Does this information change if the image is embedded in a pdf file? Or what if there was no cell reception at the time the picture was taken? I made a PDF out of 3 JPG files with Acrobat 6. I closed the PDF, opened and closed a different PDF, then extracted a page from the first...
by Bob Thrun
Dec 7, 2012 11:08 pm
 
Forum: Caving General Discussion and Questions Forum
Topic: Caver Blogs
Replies: 23
Views: 23670

Re: Caver Blogs

Does the layman or even average person have the capability to look at photos like this and determine the embedded info? Easy. Many cameras (most? all?) put a hidden block of EXIF information in JPEG files. This includes all the camera settings including GPS if that feature is turned on. The values ...
by Bob Thrun
Dec 6, 2012 11:41 pm
 
Forum: Caving General Discussion and Questions Forum
Topic: Caver Blogs
Replies: 23
Views: 23670
PreviousNext

Return to advanced search

cron