Presser Bar Lever The lever behind the Presser Foot (Photo 16) lifts both the Presser Foot and Needle Foot to permit material to be aligned under the feet and needle. Motion of the Presser Bar Lever is the same as the Knee Lift except the lever will keep the feet up. The Presser Foot Bar (lever) should be in the raised position when accessing the bobbin under the shuttle cover or when winding bobbins. The feet should be lifted off the machine's base unless there is material under the feet.
Photo 16 The Presser Bar Lever (accessed from the back of the Presser Foot) raises and lowers both feet, but not the needle. The Presser Foot is raised when using the bobbin winder or when positioning material under the foot and needle.
Needle The needle connects to the needle bar above Feed Dog and Presser Foot. The needle is held in place by a small set screw and has a specific orientation determined by the slot on the side of the needle. On our machine the slot is on the left side. When making stitches, the thread will travel inside the needle's slot (groove) and the thread is routed only to the left side of the needle. Needles come in various sizes to match the thread size and it's important to purchase the right size for your project. Needles are usually sold in packs of 10 or 100, so don't be afraid to order a bunch of extras. The tips of needles can be regular round, slightly round, sharp round, triangle point, diamond point, and even blunt depending on the material being stitched. In general, a sharp round point can pierce and stitch cloth material where the triangle/diamond point can pierce vinyl and leather material. The Schmetz Needle chart shows the different needle sizes in older and more current terminology.
Feed Dog Metal grippers under the needle (Photo 15) are that pull the material through for each stitch. * Thread Routing to the Tension Adjuster â€“ Thread Routing (Photos 17 & 18) begins with the cone of thread on the cone holder. Thread is pulled off the cone, fed through the holes in the horizontal bar and down to the machine. Thread coming off freely is necessary whether the thread is going to the machine or the bobbin winder. Thread should come off the cone easily. The first thread routing part is the small horizontal bar in the middle of the machine. Only one loop is usually needed here (Photo 19). This keeps the thread from flying wildly and puts some tension on the thread during each stitch.
Photo 17 Threading the machine varies depending on brand or model of your machine. However, it still follows some common principles. Thread in the form of a large cone is mounted on a platform with a horizontal bar above it to draw the thread. The thread can be routed to either the bobbin winder or the machine head. A lamp on the goose neck arm puts light where you need it, (usually at the needle), and the sewing machine table is against a generous table to take in the material as it sewn. Note the cleanliness. Upholstery work areas should be free of any dirt, shop dust, and liquids.
Photo 18 The first part of routing the top stitch thread is the small horizontal bar in the middle of the machine and the onto the tension adjuster.
Photo 19 Close up view of the horizontal bar. Typically only one loop is needed.
Tension Adjuster See Photos 20 & 21. Thread is further routed to the Tension Adjuster which looks like two disks, but really is one disk and a hair pin spring. This adjuster has its own bar where the threaded is routed much like the bar shown in Photo19. Thread goes counterclockwise over the top and between the two disks, then down (clockwise) to catch the hairspring and pulled up to the arm. Screwing the knurled thumb nut clockwise increases the pressure on the thread.
Photo 20 The top stitch tension adjuster has it own bar (on the right) to route the thread through before going onto the disks.
Photo 21 Close up view of the tension adjuster. Thread is routed counterclockwise between the upper disk pair and then down (clockwise) over the hair spring. When the presser foot lever is raised, the tension disks are separated making it easier to route the thread through the adjuster. The serrated thumb nut is the means to adjust the tension.