Singer 111W 105 Missing stitches

[Randy Kildow]

My Singer 111W 105 will miss stitches when  passing over a doubled seam. it works fine otherwise...  Is there something that I can do to remedy this...  sewing garment leathers and not heavy or hard..  Thread is 69/69.... prewound bobbins... needle is 16....

Edited November 16, 2017 by Randy Kildow

[Constabulary]

I´d check the needle hight and the the needle hook timing.

[R8R]

20 hours ago, Randy Kildow said:

My Singer 111W 105 will miss stitches when  passing over a doubled seam. it works fine otherwise...  Is there something that I can do to remedy this...  sewing garment leathers and not heavy or hard..  Thread is 69/69.... prewound bobbins... needle is 16....

Size 16, or do you mean a 16 leather point? I do size 18 for bonded 69. In my experience the thread can get hung up on a size 16 and not loop correctly at the hook. 

[Ogoki]

Is it perhaps a "flagging" issue?  That is to say, as the presser foot climbs onto the seam, is it no longer holding down the material before the seam, allowing it to lift and miss a stitch?  In this case a height compensation tool would help.