
Nine SUP details you need to know
For the uninitiated, it's hard to know what a SUP is really for. From drop stitch to welded taped rails, the technical jargon has a field day. Maurus Strobel, CEO of Indiana Paddle & Surf, showed me some important details and revealed some marketing tricks.
Stand-up paddle boards, the SUPs ubiquitous on lakes, look from the outside like colourful books with seven seals. Their inner workings are hidden beneath pads and logos that make a good impression at first glance. But in terms of price, there's a bit of everything. What are you really paying and when should you be wary? As CEO of Indiana Paddle & Surf, Maurus Strobel naturally lives for his products, which set the standard here. He spent an entire afternoon explaining to me many aspects to be aware of, regardless of the board or brand used.

Keyword: drop stitch
This term refers to the polyester threads inside the board. "You have to use them to make it a board, not a sausage," explains Strobel. They hold everything together and must measure exactly the same distance between the top and bottom decks. You don't have to lay the wires symmetrically to get a good structure, it's the density that counts. A cheap board will, among other things, omit this. If there are fewer wires per square centimetre, the board will be less rigid. Instead of being straight on the water, it will end up bending like a banana.
Thin boards should also be avoided: the standard thickness of six inches (15 cm) has proved its worth. Thinner boards save on elegant materials at the expense of rigidity. With cheap products, there is also a greater risk that the polyester threads will weaken or detach from the textile material over time. This "fabric" must ensure that the polyester threads are firmly bonded to the PVC layer.

Keyword: fabric
There are also different levels of quality for the textile material. As is often the case, the aim is to make it lightweight and durable. Maurus Strobel explains to me the different materials used at Indiana Paddle & Surf. He points out the coarser knitted fabric: "If you take a knitted jumper, it's obvious that a lot of liquid PVC will get stuck in it."He also explains that although this fabric requires more material, it is still cheaper than the woven version. Thinner, woven fabric uses less PVC and is the lightest on the market. It is also much more expensive to produce.

Keyword: PVC
Polyvinyl chloride plastic circulates in the fabric with which it forms the bridge. What's more, it's essential for inflatable SUPs. You'll often hear the terms "single layer" and "double layer" if you're interested in the subject. In this case, it's better to use two layers of PVC, which guarantees the quality and strength of the boards. At least, in theory. There are, of course, different qualities of PVC, plasticizers, dyes, processing methods, factories and quality controls.
Some suppliers of single-layer boards sometimes get creative: "In some cases, they talk about a fusion material, even though it's a normal single layer," explains Maurus Strobel.

But that doesn't mean single-layer boards should be abandoned, and for good reason: the increasing demand for lightweight materials. At Indiana, they can be found in the Feather range, which combines the lighter, more expensive woven fabric with a thin layer of PVC. "Lightweight is particularly important for people who use it when travelling or hiking to mountain lakes," explains Strobel. When you carry your board on your back for hours on end, you appreciate every kilo less.
But unless weight is your number 1 criterion, it's best to opt for a good board with two layers, which obviously need to be bonded together. "For double-layer boards, there's first the "real double layer", then the second PVC layer that you come and glue to the top and bottom deck," explains Strobel. "It's a very strong option, but also very heavy."
When we talk about "pre-laminated" or "fusion double layer", it's a different process: "The two PVC layers are joined in the drop stitch plant using a high-pressure, very high-temperature process. The result is an ideal combination of weight and rigidity."
Keyword: rail tapes
The top and bottom decks are held together by drop stitch threads. To form a board, you need sidewalls, called rails, which are formed by tapes. They are also available in single or multiple versions. These strips need to be very strong and, like the deck, flexible enough to roll the board up well. When your board is baked in the sun, which should obviously be avoided, the material is tested for strength. This can sometimes cause seams to burst and cheaper products are more often affected.
Rail strips are welded or glued. On this point too some people like to cheat, because the welding seems to be of better quality. "Some try to fool the customer a little," explains Strobel. With us, the two rail strips are glued together to prevent the boards from twisting," says Strobel, "but at first glance it's hard to tell because of the extremely thin layer of glue. If you look at it under UV light, you can see a yellowish trace. "After drying at high temperature, you press the contact adhesive down hard and it holds perfectly," continues Strobel. "And to make sure we don't miss, we glue one or two millimetres too much. "The main thing is that the board holds well.

When boards are sold as double-layered, it's best to pay close attention to the details. In some circumstances, the selling point refers only to the rail tapes, not the top and bottom deck layers.
Keyword: pad
The area you move around on the board needs to be non-slip and comfortable. You can often only judge this after a few hours. According to Maurus Strobel, it's best to avoid rough, diamond-shaped structures: "The square or diamond cut is ideal for surfing waves, as you need maximum grip. If you're on the SUP for two hours, you'll have the pattern printed on your feet, which may go numb. On the SUP, the best is the enemy of the good: "We use four-millimetre-thick ethylene vinyl acetate and apply a very comfortable crocodile-skin embossing to it with a heavy steel roller."

Ethylene vinyl acetate is a softer plastic that is used in particular to cushion shoe soles. Small imperfections can sometimes appear on the pad: if a single speck of dust gets between the board and the pad during manufacture, the adhesive can evaporate and form a bubble. This visual problem can be solved by removing the air bubble with a syringe and needle.

Keyword: fin
Entry-level models are often fitted with a plug-in fin which features a plastic bolt suspended from the fin by a string that slides sideways until it snaps into place to secure itself. "The water resistance of the thin rail is very low, and the whole fin system is very light and practical," explains Strobel. On SUPs, the fin is only subject to a small lateral force, so it doesn't have much to bear.
More variable and widely used, the American fin box has a screw and a small plate to hold it in place. It holds well, but proves a little difficult to use and easy to lose. On the other hand, this system gives you flexibility and a wide choice of materials. Beginners benefit, for example, from a long fin with a large surface area: "People who haven't mastered paddle technique can steer it without having to make turns all the time," explains Strobel.

The American fins also fit Indiana's two-piece fin box, making it easier to roll up the board. And the house smart finbolt tightens with a small plastic wheel. It's practical, but it increases resistance in the water a little and risks accumulating ballast: "If there's a lot of algae in the water, it can stick to it," explains Strobel. For the average user, the advantages of easy handling outweigh the disadvantages. For those who prioritise performance above all else, it's better to choose the small screw. FCS also offers fins with quick-release fasteners that can be easily fitted into the American fin box.
Keyword: leash
Not all board sets come with a leash and some come with a very simple version. You should always be attached to the leash that connects you to the board when you're on the water. "This is very important," says Strobel. "The boards have a volume of over 300 litres and are very light. If you fall overboard in the middle of a lake, you won't be able to get to safety in a strong wind." A spiral leash is recommended, as it can stretch in length like a telephone cord and won't constantly get in your way on the board. "It's best to tie it below your knee so it doesn't get in the way and you can move around easily," advises Strobel. On rivers, the leash is not attached to the leg. The danger of getting caught and dragged underwater is too great. Here there are special quick-release systems that are worn on the hip with a belt.

Keyword: paddle
Often underestimated, a good paddle is nevertheless very important. The first prices generally include a kit with a three-part aluminium paddle. Extendable, they are assembled with clips and are not appreciated by experienced paddlers: "We hate aluminium paddles," explains Strobel. "They're too hot, too cold, and sometimes they leak."
The more expensive models, light as a feather and very stiff, are made of carbon. Here's another point that manufacturers like to cheat on: "The paddle can, for example, only have a carbon design and actually be much heavier and softer, because it's made mostly from fibreglass," explains Strobel. "On the Internet, you can find genuine liars offering all-carbon paddles for 69 francs. That's less than the manufacturing cost!" In its kits, such as the Family Pack, Indiana favours a fibreglass shaft and injection-moulded plastic blade.

Keyword: craft
A SUP doesn't come off the assembly line entirely automatically: "The drop stitch material is delivered in 300-metre rolls weighing tonnes," explains Strobel. Once the computer has milled the basic shape, you have to continue by hand. The top and bottom decks are fixed with rail tape, the board is inflated and checked to see if it is twisted or not. "There are many more steps by hand before the board is finished. If the work is sloppy, the board won't look good," and if the material is cheap, a supposed bargain will quickly turn into a rather expensive and unwieldy air mattress.
Click here to check out the entire SUP range.
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Simple writer and dad of two who likes to be on the move, wading through everyday family life. Juggling several balls, I'll occasionally drop one. It could be a ball, or a remark. Or both.