In our home business, we sewed a ton of Velcro. I used a zig-zag stitch that went just off the edge of the Velcro on one side. I used a size 90 universal needle, and Guterman polyester thread. Towards the end, I was frustrated with the Guterman thread breaking and snarling above the needle, so went to Dual Duty (Coats and Clark), which worked better.