Good Design: The NRS Tie Down Strap
Introduction
For obvious reasons, a number of big trips I had planned were canceled this year. However, my family and I were still able to do a couple of outdoor adventures, closer to home - camping, canoeing, rafting, backpacking, and even some hammocking.
For many of these activities, we needed to tie something to the car, a backpack, or a tree. I own a couple of small ratchet-strap systems, bungees, and many sections of nylon webbing (and, of course, rope) but I wanted to try out a strap using a camming mechanism.
A cam strap is one where the locking mechanism is supplied by the friction between the webbing strap and a metal section usually with a roughened surface, like knurling or teeth, to increase the coefficient of friction. The locking position between the strap and cam is maintained through a torsional spring such that if the strap is pulled the metal cam will tighten even more onto the strap increasing friction and thus preserving tension on the strap.
User Experience
I heard and read that NRS makes very reliable and robust cam straps, so I bought a few NRS tie down straps earlier this summer to try out in a variety of places.
I started with the obvious place - a river. After all, NRS stands for Northwest River Supplies (I had to look that up) and heavily markets their products towards adventurers drawn to rivers and lakes.
I rented some rafts and tied one to the rack on top of our vehicle with my four new NRS straps. We were rafting with another family and they tied their raft to a truck with a ratcheting system. This natural experiment through comparison was exciting.
It didn’t take long for NRS to score the first win. The NRS strap was super simple to operate and I had my raft tied down much earlier than our friends’ raft. I went over to their truck to help them and we struggled to untwist, set, and tighten the ratchets correctly at various points to his truck’s bed.
The second NRS win came just 10 minutes later on the road. I was leading our caravan, but I noticed in my rear view window that their raft was flapping all over the place. I slowed down so that we wouldn’t lose their raft. My raft seemed to be totally fine. This is partly due to the orientation of the rafts, but regardless their ratchet system was sliding down and around the raft and starting to fail. Eventually, they had their daughter hold onto a strap through one of the windows so that we could continue at a speed faster than 40 mph.
The third win came from untying the straps. It was just as fast and easy to release the tension, unload our raft, and move on with our activity. True, cranking on the ratchets might be able to ultimately produce more tension, but if you have enough tension… you have enough tension. And the NRS straps had enough tension. Furthermore, releasing and untying their ratchets were a lot more cumbersome. In addition, we noticed a smooth surface on the back side of the metal buckle on the NRS straps which, if position against the pressurized surface of the raft, would reduce the puncture potential if someone overtightened. The ratchets had to be more carefully positioned to reduce the puncture potential.
A few weeks later, I used the same straps to tie down a child’s kayak. This kayak has a small hole through which the NRS webbing could pass (see figure below). The webbing width was perfect. A rope would have done the job but then I would have had to test my bowline or trucker’s hitch skills, which probably would need a few iterations. The bungee cord hooks couldn’t have made it through that hole and so they would have been useless in this scenario. The ratchet system webbing is wider and would have had to fold in on itself a lot more which would have been cumbersome in this case as well. NRS straps score another win.
I started keeping my straps in the car, and when my 9 year-old wanted to tie her hammock to a tree a little too far away for the hammock’s straps, NRS saved the day (see below). The tension was maintained and it held her (and me!) just fine without slipping.
Later in the summer, the NRS straps worked great for tying down a tarp and some bags for a camping trip later to Coral Pink Sand Dunes, but a more unconventional use was simply holding together our bag of sand toys which unfortunately doesn’t have a cover (see below). Admittedly, the bag itself has some things to be desired, and the kids always overfill it with sand toys, but the NRS strap kept the toys from falling out the entire trip.
Reading about a few others’ experiences online, the NRS strap can be used as a belt since the strap width is small enough to fit through smaller loops on pants, packs or other clothes. Then, if needed, it can double as a tourniquet, holding a ski boot together after a buckle bust, tying off a bear bag in the trees, or repurposed as a clothes line, among other things.
So, what else makes all the above use cases successful? Beyond some of the things mentioned and observed while discussing the above applications, I think there are a few other features that make the design of the NRS strap a little better than other options.
The size is just right. With thinner webbing, even if the loads could be held, my hand might struggle to grasp and pull sufficiently to engage the camming device. Any wider, and it becomes too bulky and awkward to carry around and wouldn’t be able to do as many things.
Adjustable and a variety of lengths. NRS straps come in a variety of lengths so matching a length to a continual purpose would be ideal. But combining straps to increase a required length is also possible and the simple design allows the strap of one section to be inserted into the cam of another. If the strap does fray at the end, making a 3-foot belt with the remaining section is an option, although cutting a strap shorter is irreversible. Still, I don’t see a lot of ratchet systems used for belts these days.
Labeled straps and buckles. All NRS straps are labeled with their lengths directly into the stitching of the webbing and on the buckles. These labels (especially on the buckle) are not going to fade anytime soon and save time that measuring out a rope would require for an intended purpose. Many times a pile of ropes need to be explored individually before finding one that works. A pile of NRS straps is much easier to scan. (Of course, cutting a strap shorter invalidates this benefit of that label, but how many cam strap belts do you need?)
Coils can be tight and stay together. This is a small thing but many small things make good designs. Because of the NRS strap’s buckle’s small form factor, in connection with the flat webbing, coiling is straightforward and efficient. Even my children can do it. The coil could be set to hold itself even tighter using the cam device with a little more effort, but I’ve found that it stays relatively coiled sitting on a shelf without the camming mechanism. My bungee cords with hooks, on the other hand, never seem to hold together and end up in a knotted pile.
Design Principles
First of all, the stitching on the NRS strap is clean, tight, and solid. They evidently have a good process in place to keep manufacturing errors minimal and produce consistent results. There is an aesthetic of simple but high quality workmanship with every stitch that resonates with users. Since “holding things down without slipping” is the core function of these straps, a designer should make sure that the look and feel of these straps is consistent with, and supports, that foundational function. If the strap came frayed with random loose threads, even if functionally it was fine, the user’s confidence in the product would be lower. As designers, we should make sure elements of our designs reinforce the underlying function, even with completely aesthetic parameters of color or shape. Products that work but don’t look like they will work have a hard time entering the market.
Secondly, the smooth back side of the buckle will protect air-inflated assets from rupturing under pressure and the strap size, both width and length is perfect for a variety of applications. It goes without saying but our own designs should do no harm to other products or other people. This is an important design principle to consider but sometimes is bypassed. Most products, after all, will interface with other things that the designer can only partially foresee. A good question to ask at some point during the design process is What will my design come in contact with during its entire lifecycle? If you or I knew that our design was going to be touching skin, rubbing against something sharp, used in a humid environment, touching food, etc. we would be heavily concerned with those interfaces. Some of those interfaces with other things may be obvious, but some may not. The use cases a customer will devise for our products may be much larger than we think. We can’t predict all of them but we can be aware of this inevitability and take a moment to question every side, slant, or surface.
Thirdly, the NRS straps are durable, strong, easy to use, easy to store, and light and small enough to carry around and store in a vehicle. It’s satisfying to think that a user values our product so much that they carry it around with them on their person or in their car. This isn’t always the end goal with a product but the design principle to takeaway is that ease of use is a big driver for adoption. If our product takes too long to get out, set up, calibrate, turn on, engage, prepare, or assemble, it’s not going to benefit the end user as much. We should all carefully evaluate how long or how effortful it is for just the initiation phase of using a product. If it’s too heavy, large, or awkward, individuals might think twice before dedicated the minutes required to move, adjust, and position the product, especially if they will only use it for a few minutes. The set-up time versus the use time should be a small as possible. Again, this isn’t always possible but it should be considered.
Are there other straps on the market that will fit your needs? Absolutely. But NRS does a good job, at least in their NRS tie down straps, tying these design principles together (pun intended).
Editor’s Note: This article is part of a new series on “good design” where we highlight products, systems, and services that embody design principles worth aspiring to. We invite our readers to submit a Good Design article to the BYU Design Review, in hopes that over time we will collect a large number of articles that inspire and instruct us toward better design.
