Singer Heavy Duty Sewing Machine kerstean June 10, 2019 June 10, 2019 Comments Off on Singer Heavy Duty Sewing Machine Here is a step by step guide to threading the Singer Heavy Duty sewing machine. You can also watch a video tutorial here. Share this:Click to share on Facebook (Opens in new window)Click to share on Twitter (Opens in new window)Click to share on Pinterest (Opens in new window)Click to share on Tumblr (Opens in new window)