rope weights -- static specifically

[mtngrrrl]

I was looking around at some websites, and I noticed that dynamic ropes are generally listed with their total weight in kilograms and their lengths in meters.

 

Static ropes, though, are often listed in pounds/ounces and foot measurements. I was wondering if anyone knows why this is.

[cj001f]

Static ropes, though, are often listed in pounds/ounces and foot measurements. I was wondering if anyone knows why this is.

Static ropes are usually listed as g/m or oz/foot because they are usually sold bulk, i.e by the meter/foot.

 

Most catalogs I've seen usually compare ropes by the meter or foot though.

[lummox]

it is because cavers are freakin metric system luddites.

[cj001f]

it is because cavers are freakin metric system luddites.

freakin Reagan

[kurthicks]

it also helps to distinguish between static and dynamic ropes. if both were measured in mm, it could lead to people leading with statics.

[boatskiclimbsail]

A few years ago, you would find most all US made ropes listed as "200ft" or "165ft" instead of 60m and 50m, and their weights would be listed in pounds, etc. etc. Recently, for whatever reason, the marketing of dynamic ropes went completely metric, along with the marketing of almost every other piece of outdoor gear and climbing gear. Maybe it was the kN, maybe it was the european gear manufacturers, who knows. In any case, static rope is used primarily for non-sport applications, rescue, insustrial, etc. Most of the industry in this country still uses imperial measure, and is VERY resistant to change. We used to hate it with a bitter passion in my machine shop when some engineer would hand us a drawing in mm instead of in. I would suspect that since a lot of the same feelings exist in the realms which use static rope, that they sell more if it is still listed and sold by feet / pounds. For example, someone who knows they need a 7/16" static rope to fit some standard may not want to deal with buying one marked "11mm" or 1/2" vs "13mm". Even though the rope hasn't changed, it's listed diameter has changed by 1-3%. Something else I would imagine affects this is the unit price of the rope. When you sell by the meter and are competing with companies that sell by the foot, your prices appear 3 times higher to someone not paying attention.

 

Those are my best guesses but what do I know...

[lummox]

it also helps to distinguish between static and dynamic ropes. if both were measured in mm, it could lead to people leading with statics.

you are kidding. right?

[mtngrrrl]

Thanks for the responses. I understand that when ropes are sold from a spool the measurements would be given in oz/foot. When I started climbing, we discussed ropes in ft. Now we only talk about them in meters.

 

In any case, static rope is used primarily for non-sport applications, rescue, insustrial, etc. Most of the industry in this country still uses imperial measure... I would suspect that since a lot of the same feelings exist in the realms which use static rope, that they sell more if it is still listed and sold by feet / pounds. For example, someone who knows they need a 7/16" static rope to fit some standard may not want to deal with buying one marked "11mm" or 1/2" vs "13mm".

 

boatskiclimbsail, can you explain the non-sport, non-rescue industry applications where a static rope is used? Theater is all I can think of. Practically speaking, would these people really buy a rope from an outdoor retailer, or would they get static cord from some cheaper industrial source? Are they using BlueWater ropes (for example)?

[Thinker]

some applications off the top of my head:

tree cutting

window washing

construction/inspection applications

sailing?

fire fighting (rescue)

military (rapelling)

Law enforcement

[cj001f]

Practically speaking, would these people really buy a rope from an outdoor retailer, or would they get static cord from some cheaper industrial source? Are they using BlueWater ropes (for example)?

Practically speaking the manufacturer would spec it in oz/ft for those markets, and since most retailers just parrot manufacturers numbers, the retailer would just use those.

[boatskiclimbsail]

Thinker is on the right track, military and law enforcement is getting pretty specialized but they use the same static rope we do (except black or olive). NFPA qualifies the same static ropes you'd use in bigger caves for fire rescue and the like. Work positioning is a big one, though their stuff is sometimes more specialized to the job. Riggers use static rope all the time, I've used it myself in the theater. Sailing is a "sorta" area, nylon doesn't do well in direct sunlight, where most of your rigging is all of the time even at the marina. They make static rope that has polyester sheaths and even some with poly cores as well. I use my old climbing ropes for mainsheets and jacklines and stuff like that but I come across replacements for them (wear out ropes) faster than the UV degrades them.

 

There are certainly more, but off the top of my head those are probably the biggest industries. Practically speaking, they would probably buy it from the cheapest place they could find it. Sometimes this will be an industrial supply, sometimes a weeekend sale at the mountaineering shop. Personally I just had enough of it lying around that it just made sense to use for other things. My main uses for retired gear are sailing, rigging, utility straps and tiedowns, and toys (rope swings, etc). Occasionally some art comes out of it too, for example I have a set of wind chimes made of an old set of tricams (the HUGE ones) and some old hexes.

[mtngrrrl]

Thanks for the follow ups. Cool info.

[kurthicks]

it also helps to distinguish between static and dynamic ropes. if both were measured in mm, it could lead to people leading with statics.

you are kidding. right?

 

yea, to a certain extent. i sure hope someone wouldn't ever be that dumb

[iain]

yes in rescue applications it's all about the english system. Kind of dumb talking about a 300ft rope supporting 2kN loads, but everyone knows exactly how big a 300ft rope is, and how many you need to do a particular highline or lower down mt jefferson, etc and you can think of it in football fields English system should be banned.