Marking the rope.

[Ralph E. Powers]

I'm planning to buy a 210 or a 250 foot length of that nice PMI Pit Rope... I want to mark it in the middle (at the 105/125' mark) to know where to "split the rope in 1/2 using a spanish or french bowline or a double bighted 8 knot... mainly for training purposes to have 1 rope be able to service 2 cavers, i.e. both ends going down the side of a cliff face.
I wonder if a Sharpie brand marker would have components/chemicals in the ink that may over time degrade the strength of the rope? Or is there a better ink/pen that can do it?
I did a forum search using key words: sharpie, marker, marking, rope and got nothing, except a ton of topics with no clear topic heading to lead the way.
I know it's ok to mark the ENDS of the rope because there's virtually no stress at all on them... but the middle??

[Mark620]

A sharpie has chemicals that are bad for nylon.

[fuzzy-hair-man]

This link might help:

http://www.traditionalmountaineering.org/FAQ_MiddleMark.htm

It appears blue water has a rope marking pen that does not harm the nylon in the rope. (They recomend it for thier ropes anyway I don't know what PMI might say perhaps they have a similar product?)

Don't worry I found it:
http://www.pmirope.com/rigging-gear/index.aspx?pageID=24&productID=583&productMasterID=583

[Scott McCrea]

Here is a notification from the UIAA^:

End-users of climbing ropes have been marking their ropes to help rope management. At the last Plenary Session the Safety Commission, together with the attending rope manufacturers, dealt with this problem. It was concluded that certain products act aggressively on polyamid. As a result the Commission has published the following NOTIFICATION:

Notification Concerning the Marking of Ropes

Tests done by the UIAA Safety Commission and some rope manufacturers have shown that marking ropes with liquids such as those provided by felt-tipped pens can damage them; even with those markers, sold specifically for marking ropes. The test results have shown a decrease of up to 50% of the rope strength, more correctly: of the energy absorption capacity of the rope (expressed by the number of falls in the standard test method in accordance with the UIAA Standard101).

Therefore the UIAA Safety Commission warns against marking a rope with any substance that has not been specifically approved by the rope manufacturer of that rope.

It is not possible for the UIAA Safety Commission to test all markers that are commercially available and can be used for marking ropes. Furthermore it would be impossible for the UIAA Safety Commission to keep such information up-to-date. In addition, the effect of any rope marker seems to vary with the make of rope. Hence, all the UIAA Safety Commission can do is to warn mountaineers and climbers.

Issued: April 2002

[Ralph E. Powers]

Notification Concerning the Marking of Ropes

Tests done by the UIAA Safety Commission and some rope manufacturers have shown that marking ropes with liquids such as those provided by felt-tipped pens can damage them; even with those markers, sold specifically for marking ropes. The test results have shown a decrease of up to 50% of the rope strength, more correctly: of the energy absorption capacity of the rope (expressed by the number of falls in the standard test method in accordance with the UIAA Standard101).

Therefore the UIAA Safety Commission warns against marking a rope with any substance that has not been specifically approved by the rope manufacturer of that rope.

Thanks for that Scott... Now anyone have any ideas? ... anyone? Bueller?

[Scott McCrea]

Don't clean the center six inches or so. The dirty spot will mark the middle.

But seriously, I gave up on trying to mark the center of ropes. I just have to find it the old fashioned way.

[hank moon]

a friend of mine weaves colored surgical suture into the sheath at the midpoint.

[Dave.W]

Anyone know if food coloring would have an adverse affect on nylon?

[fuzzy-hair-man]

Here is a
Therefore the UIAA Safety Commission warns against marking a rope with any substance that has not been specifically approved by the rope manufacturer of that rope.

Don't worry I found it:
http://www.pmirope.com/rigging-gear/index.aspx?pageID=24&productID=583&productMasterID=583

This marker is sold/recommended by by PMI for rope marking so it should be approved for use on thier own ropes at the very least.

[Dane]

Sounds like a decent suggestion, Dave W
A food-grade, water-based colorant may have to be re-applied on occassion, and if/when that part of the rope got wet, some of it would come off on anything/anyone touching it, but it is essentially inert. (even more-so than that used for doing dye-tracing)
Using such a dye would alliviate any concerns on toxicity, rope damage, etc, so it may be worth some aggravation.
If you want to try that Ralph, let me know and I can hook you up with some that you can dilute to whatever strength you like.

FHM - While according to Scott's quote, the adverse test results were present even on markers made for that use, Sharpie's copy sure sounds convincing -
"The Sharpie capillary marker is a Trace Element Certified (T.E.C.) marker meets the requirements regarding trace element content for the nuclear energy, aerospace, electronic, aeronautic and ship building industries. Each marker is identified with the batch number of the ink."

I thought about label and shrink tubes, but that probably wouldn't last long on those longer drops where you used all 200' of the rope.

What about the colored, nylon dip sold for marking/sealing the ends of ropes? It shouldn't hurt the rope (it is nylon based) and a few separated narrow bands should go through a rack without too much trouble.
Any thoughts?

[Dwight Livingston]

What about the colored, nylon dip sold for marking/sealing the ends of ropes? It shouldn't hurt the rope (it is nylon based) and a few separated narrow bands should go through a rack without too much trouble.
Any thoughts?

I've never heard of any nylon based dip coats. They are mostly vinyl or neoprene. Whatever it is, it will include a plastic resin and a solvent. The solvent keeps the plastic liquified until it evaporates. For products like Whip End Dip or Polyshield, the solvent is water based. I looked for some test data on it's affect on rope and couldn't find any. The products are advertised for only rope ends, with no claims for rope strength.

Dwight

[chh]

Fabric Marker (non-acidic) or weave some thread through the sheath at the middle. Neither one will last forever, or be terribly easy to see when your rope is covered in mud anyway.

The other thing you can do is just coil your rope while it's doubled if you rig like that frequently.

[Phil Winkler]

Anchor lines on boats are often marked at 10m intervals using colored nylon tags forced between the fibers, but those lines are almost always laid rope rather then braided since they must be dynamic. However, using colored threads woven into the outer braided sheath ought to suffice and endure passing through a rack too.

[Ralph E. Powers]

Well, I guess I'll have to wait til I actually buy the rope and go from there. Dunno about weaving colored threads through the sheath ... it's woven pretty tight and for a good reason, considering it'd be roughly in the middle don't think that portion would want to be compromised at all eh? Especially as it was observed that not only would this rope be used for training purposes it would also serve as a long rope for a single drop.
Sigh, reckon as Scott said to do it the old fashioned way and find the middle by grabbing both ends and pulling them together til the middle bight comes up and tie the appropriate knot.
Just was wondering if there was a shortcut way to do it.
The thought of something that might "possibly" damage the rope doesn't do me any good. Dispite my own extensive vertical experience ... I still get a bit of the butterflies when I'm mid-way up a long drop climbing out.
Made me wonder if perhaps PMI might want to think about selling speciality ropes that are akin to how some dynamic rock climbing ropes are made with two different sheaths meeting up at the middle of a 50 meter length. IMO there's virtually no difference between the EZ-Bend brand and the Pit rope except for the red threads woven (via factory) through out the EZ-Bend.
Gonna have to give those guys a call sometime.
Thanks for the replies... makes for a good discussion though huh? Any other ideas... keep 'em coming.

[hank moon]

Thanks for the replies... makes for a good discussion though huh? Any other ideas... keep 'em coming.

Weaving a few small-denier yarns through the sheath does far less damage than normal use!

Probably the best "packaged" product out there for marking:

http://canyoneeringusa.com/shop/view_pr ... %20320215B