How WASP Bags Are Made Waterproof
What Makes a WASP Bag a Completely Waterproof Bag?
Well, there are three key WASP Bag design features that ensure the things that just shouldn’t get wet, don’t get wet. They are:
- A super tough 500D PVC Tarpaulin material
- Thermowelded construction
- The unique fold over seal mechanism
Let’s look at each in turn.
500D PVC Tarpaulin Material
PVC Tarpaulin is a bit of a modern wonder material. It’s incredibly versatile with applications as broad as truck sides, tents, inflatable boats, temporary awnings and of course, waterproof bags. PVC tarpaulin is waterproof, stain resistant for easy cleaning, anti-static as well as having the characters of flame-retardant, UV-protection, antibacterial and mildew resistance. It’s also very resistant to extreme temperatures. Check out this article for a full rundown on what makes PVC tarpaulin the best material for waterproof bags.
All types of PVC tarpaulin possess these characteristics to some degree. However, like most things in life, not all PVC tarpaulins are created equal. The type of PVC tarpaulin used for WASP waterproof bags is 500D. This refers to the thickness and density of the fibres in the material, with 500D representing a density rating of 500. Your common household tarpaulin has a density of about 100, and the scale goes up to 1000. In this photo, you can see the thickness of the fibers in the 500D PVC tarpaulin (on the right) compared to the standard PVC tarpaulin (on the left).
500D PVC tarpaulin is the perfect balance between durability and pliability. It has great tear strength meaning it won’t rip, yet it’s not so stiff as to be uncomfortable to carry or difficult to seal. These characteristics mean 500D PVC tarpaulin is the perfect material for WASP waterproof bags. It is a completely waterproof material, and its toughness prevents any small holes appearing and letting water in.
Thermowelded Construction
Merely stitching the material together is not going to cut it if you want a truly waterproof bag. The process of stitching creates thousands of small holes all of which compromise the ability of the bag to keep water out. To over come this in the past, a waterproof seal is often put behind the stitching to keep the water out – think a big piece of sticky tape. The problem with this approach is that these seals often peel away or crack with time, reducing the lifespan of the bag’s waterproof status.
To avoid this problem all together, WASP Bags are constructed through a process called thermowelding. The principle is the same as welding metals, you use heat to melt the materials together where they bond, creating a join. Instead of stitching the materials together, heat is applied to melt them together. The fibres join together to create a strong, durable and most importantly, waterproof seal.
By thermowelding WASP waterproof bags, the seals remain tighter and less prone to peeling or cracking later on. It is the thermowelded seals that give WASP Bags such a long life.
Unique Fold Over Seal
The unique fold over seal is what brings the 500D PVC tarpaulin material and themowelding together to create a totally waterproof bag. To seal a WASP Bag, or any other dry bag for that matter, you need to fold the opening over itself 3 times. By folding it firmly and tightly, the inherent friction in the PVC tarpaulin material means it grabs on itself. This creates an airtight seal, and that is the secret to making it waterproof. If air can’t get in (or out), how can water? It can’t.
The folds must be firm, crisp and tight. If they are not firm or tight enough, there won’t be enough friction to create an airtight seal, and the bag won’t be waterproof. You also need to ensure the bag isn’t so full that you can’t fold the top over sufficient times. The great thing about an airtight seal is that if you don’t expel the air inside the waterproof bag (which you do by pushing it out whilst lightly holding the first fold), it will float on water. And it can double as a comfy pillow! To see just how easy it is to create a waterproof seal, check out the video over here.
So it’s the three key design features of 500D PVC tarpaulin material, thermowelded construction and the unique roll seal that all work together to make WASP Bags the best waterproof bags going around!
