I do FMQ on my Brother PQ1500 in a table, not a frame. I am inconsistent with remembering to lower the feed dogs and I don't have any issues either way. Is it a particular machine that is the issue? I don't even remember to set my stitch length to zero to prevent the feed dogs from moving. I learned to FMQ on a dinky mechanical ordinary Brother from Costco years ago. The feed dogs didn't lower. I did set the stitch length to zero No issues but a tiny throat.