I was thumbing through a catalog today, and I saw for the millionth time "accessory cord". It made me curious for the hundredth time, and I started looking into it. And I found this.

5mm dia, supposedly a one TON breaking strength, and it's $20+shipping for a 20 foot spool. It's pricier than paracord, but for tthe added strength, it might be worthwhile even though I like a dynamic line better for most things.

My question is, has anyone worked with this kind of cord before, and if so, how does it knot compaired to paracord?

I use this type of cord often, for knot tying practice (a hobby of mine). Notice I said "type of cord". I have several different 5mm cords I practice with and they are all different. Some are stiffer, some are harder, some are softer, some are more flexible than others. They were all bought at outdoor recreation and/or climbing supply stores, so they are all good quality cord - just different from each other.

You can't really tell how a cord handles by looking at a picture or reading a description. And "holding a knot well" depends on the use. For example, stiff, hard cords do not hold bends as well as softer cords, but they're great when used for constrictor knots around softer material.

Thicker cords do not usually tend to jam up as much as smaller cords. So a smaller cord may feel like it holds "tighter" (because it's jammed). However, untying a knot in thinner cord can be near impossible sometimes. Sometimes you have to give up and cut the cord.

The above are just generalizations, and are not hard and fast rules for every cord in every situation. That's why you need to know several different knots for a given purpose. Depending on the specific cord you have, your previously tested "secure" knots may slip and other knots you considered less trustworthy may hold like a bulldog. In my experience, a softer more flexible cord tends to find use in more varied situations than a stiff or hard cord. YMMV of course.

This looks like the tech cord from New England Rope, commonly refered to as New England Tech Cord. I've not seen it branded as "Maxim" before, Google turns it up as the 'climbing' page on the New England Rope site:

Maxim Climbing
click on accessory cord
click on Tech Cord; Technical Data Sheet

You can compare that to the sheet from the Safety & Rescue page. It's the same stuff. The key is the Technora Core.

I carry some 3mm (3100lbs) New England Tech Cord in my pack and it is very cool stuff. However, there are trade offs. It is somewhat stiff and you can't melt the ends due to the high melting point (this could be an advantage). Probably the best bet is to use waxed whipping twine.

You can find some ramblings about high tech cords in this CPF thread.

The 3mm is going to be thicker and much stiffer than paracord, and the 5mm even more so.

My understanding is that they can lose a lot of their strength depending on the knot.

big pic of 3mm tech cord

-john

* I haven't found a source for the 3mm in a long time.

(oh, also be careful. they also sell an 'accessory cord' which is not the same as their 'tech cord')

OK, so does anyone know the difference between a "tech cord" and an "accessory cord"?

Basically, what I'm really interested in is using it replace paracord in shelter making, specifically the hanging of the hammock (550 line hasn't broken and dumped me yet, but I'm coming across such stories more and more) and to act as a "ridgeline" when using tarps as structure under snow in winter.

A couple of things to consider are cost and multiple use potential. Tech./accessory cord is not designed like paracord and does not have the distinct multiple inner core bundles; it is a single bundle of continuous fibers, which might not provide as much potential in terms of various uses.

Paracord will likely pack down better then tech/accessory cord and costs considerable less. Yes, tech./accessory cord has greater load capacity then paracord, but if you plan on using it for shelter construction, I would stick to the paracord.

Pete

If you're concerned about the strength of 550 cord, here's a story of how we've used it. We raised a 50' radio tower with antenna by running a double length of 550 cord from the tower, through an eye hook on the roof peak of a garage down to the bumper of a Jeep. I was more concerned about the Jepp keeping traction than the strength of the 550 cord.

In this *specific* case, they are very different beasts. The tech cord has a Technora (fancy, high tech fiber) core and the accessory cord has a more normal core. (Nylon).

I think you need to make sure that you examine the specific cord when comparing as I don't think you can assume a given "tech cord" will be made the same way.

As far as I understand, the weakness of this product is tying/untying knots or otherwise sharp bends. I think this is related to what Pete says -- there is no weave to the inner core, so if you break a fiber anywhere along the length, it stays broken and reduces strength. Over time, that would add up.

I think the knot issue also is part of a "shear" concern, where the knot acts as a sharp bend which increases the chance of breakage. I assume this is partially due to the lack of give in this material, but I'm certainly no expert.

How much of an issue this would be, I don't know. But I tend to keep my tech cord for emergency use where I want to have a very strong cord, and would plan to retire it fairly quickly.

Again, as Pete suggests, for your utility use, the paracord/accessory cord may be better.

Probably just inspect it and replace it before it gets too ratty, and maybe carry some spare.

I tend to also like Spectra cord which is another (but different) high tech cord. This is braided and much more flexible. It is a bit 'slippery'. The 7/64" is very small, light (I think it floats) and rated for 1200lbs. It melts (makes it easier to deal with the ends) and has some give.

While you may perfer paracord/accessory cord for everyday use, the Spectra cord is a nice backup cord because it is very light and compresses well.

YMMV.

-john

Spectra line does not melt, the sheath does but the core will not.
I used to work in a climbing shop and cut the stuff for customers all the time. You need to cut back the core and the melt the sheath around it sealing the core.
Spectra and its cousins are for climbing applications such as creating anchors. It is not ok to use as a prussik. The Maxim product is a little different in that it can be used for friction knots.

All in all 550 is a better all around choice.

I know from direct experience, Spectra cord from Berkeleypoint.com does melt (it has no sheath), and Technora based core of the New England Tech Cord does not (but as you point out, the Nylon sheath does).

Take a look at this test of high tech cord and you'll see the melting point of Spectra is noted as low.

Comparative Testing of High Strength Cord

-john

550 cord has an almost mythical status as the end all be all of cord here. I've got hundreds of feet of it and I use it for a number of things. However I also have vairous sizes of tech cord that I use. Paracord is great but it has a lot of stretch, it can be almost impossible to untie knots from in some cases, and while it's strong, it's not umbreakable, it's abrasion resistance isn't as high as tech cord and I'd never trust my weight to it. On the other hand, tech cord is expensive, some knots don't work as well with it (easily worked around by tying knots that do work with it.) For holding a hammock up, I use tech cord, I don't want to roll over and fall when the paracord breaks. For hoisting my pack in a tree though to keep critters out of it I use paracord.

Different cords for different uses. Paracord works for most but like I said, I'd never trust my weight to it.