I'm thinking about ordering a New England 10.2 60 meter rope from REI that's only like $140. The only problem with the rope, besides the fact that it's ugly, is it has no middle markings.
Is it safe to use a Sharpie (or something like it) to mark the middle? I'd hate to somehow corrode the sheath and not realize I'd weakened it until I'm belaying you on that project you keep taking whippers on. What do rope makers use to mark the middle?
Thanks for any advice.
Here's some info from Stewart Green from his page here:
How do I mark the middle of my rope?
If your rope doesn’t have a middle mark, then you can use a black permanent marker to designate the mid-point. Look for a marker made specifically for your rope by checking the manufacturer’s website. Be aware that the UIAA Safety Commission did tests with felt-tipped permanent marker pens, including those made specifically for marking ropes, and found a decrease in the “energy absorption capacity of the rope.” They therefore warn against marking a rope with any marker or substance not specifically approved by the rope manufacturer. But they also say that the chances of a rope breaking where you marked it as “nearly zero.” So you take your chances.
Marking With Tape or Thread
Some climbers use a piece of tape—duct tape or electrical tape—wrapped around the middle of the rope. This works…for awhile, but after a few pulls through carabiners the tape is gone. An alternative is to use some bright sewing thread and stitch it through the middle of the rope for a dozen or so turns. This works too but if the rope gets dirty, than the thread gets dirty. Using thread or tape won’t harm the rope and both are easy to replace.
And another post from Traditional Mountaineering:
No manufacturer will condone the use of permanent marking ink on the middle mark of a climbing rope. This would require the chemical analysis of the ink (which might be different over time) by the rope manufacturer. Bluewater sells a (non-permanent) marking pen with a Ph only approved for their own ropes.
The option of marking the middle of a climbing rope with tape is also questionable. How does the adhesive in the electrical or athletic tape react over time with the materials of the rope? One climbing rope wholesale representative states that the Ph of athletic tape may not damage the rope but points out that tape can come loose quickly and slide away from the original placement.
So, everything I found is kind of conflicting. Some sites claimed it wasn't a good idea to use a marker and that in some cases it weakened the rope by 50%. Then, in others it noted the weakness but said it wasn't really a problem. And tape can move and the chemicals can possibly harm the rope, too. And thread? Really? Maybe I'm crazy but it seems like the worst idea to actually pass a needle through the actual core of the rope!