Checking And Repairing The Retaining Ring Cap Spring; Measurement And Adjustment Of Machine Timing - Strongarm Walking Foot Sewing machine User Manual

Checking and Repairing the Retaining Ring Cap Spring

At the top of the bobbin retaining ring, there is a curved plate with a roughly triangular slot
called a retaining ring cap spring.
Inspect this slot for burrs
If the fabric moves while the needle is in the fabric, the needle can bend and strike the edge of
the cap spring, causing a small burr, or rough edge. If the thread catches on this edge, the
thread will fray, or the stitch will fail to form.
To repair the burr, remove the bobbin retaining ring and inspect the cap spring on the top of the
ring. If there are any burrs on the spring, file them smooth with a small strip of sandpaper.
Make sure you don't over-file the spring and create a sharp edge.

Measurement and Adjustment of Machine timing

Retiming your Strongarm sewing machine should only be considered after all other
potential solutions have been tested. Please see the chapter on troubleshooting first.
Make sure to change the needle, check for correct needle insertion and check the cap
spring for burrs before considering retiming your machine.
The Strongarm 2000U-33 is a robust machine, but occasionally a broken needle or a thread
jam can knock the machine out of timing. Retiming a Strongarm sewing machine is a simple
business, and can be performed by machine owners.
Before re-timing your machine, it's important to know how a sewing machine actually creates a
stitch.
Underneath the machine, a rotating hook oscillates, or rotates back and forth around the
bobbin. When the needle swings down towards the bobbin, the hook catches the thread from
above the eye of the needle, and loops it around the bobbin, creating a knot, or a lockstitch.
For a stitch to form, the hook needs to swing past the needle just when the needle is coming
up from its lowest point, and it needs to brush past the needle very closely.