If i was having this problem, i would try sewing in reverse first, on a test strip of course. If it was stitching correctly in that direction, I would start stitching in the forward direction over the top of previous stitches (reverse). If it them birds nests or messes up, it would appear to be more related to needle size than the reverse direction. In that case I would change to the next size larger needle. If there is not enough space in material where needle pierces along with thread being doubled up in same hole, it may cause problem you are having. Hope this helps.