I'm making a modified GVP Gear Ultralight Pack and am having a difficult time sewing the foam. I'm using a size 16 denim needle. The foam is 1/2 in thick. The bottom stitches are bunching and gathering a bunch of thread. The top stitches look normal. I assume its a tension issue due to the thickness of the foam and the fact that the sewing machine is fine when sewing other fabrics. What should I do to the tension? Or is it something else?
Thanks- April
