How to repair heavy duty nylon seam? I bought a heavy sandbag which is supposed to be able to be dropped. Given the good ratings it has, I assume it had a manufacturing fault as the seam exploded the first time I dropped it.



Luckily, as insurance I bought this sewing awl, that comes with waxed thread that is thicker than what the sandbag is sewn together by.

Will this thread be suitable, and can you please point me to the best stitching method/pattern for repairing this seam, given that I only have this awl to hand?

Edit: I also have 50mm wide nylon webbing to hand, perhaps I can use that to reinforce the seam?
The way I see it, even the base material is not cut / prepared really properly. Even if you make a very good stitching, there is a chance that the material itself will fail during the next "shocking experiences".

I would do it in two steps:


stitch as good as possible, to make sure that the sand will stay inside. Please stitch each layer individually, for increased strength;
Wrap the area with strong ribbons (let's say, similar with the safety belts in cars; similar to wearing belts for pants). Be sure that the belts close with good quality metal, not with cheap plastic.