What Is A Knitting Machine Sponge Bar And Where Is It Located?
Flat bed knitting machines use a sponge bar to hold the needles in place as the carriage moves back and forth. It is about 3/8″ wide and runs the whole length of the bed. Sometimes this bar is referred to as the needle retaining bar. Many ribbers also require one, although some use a bar without any foam, such as in the Brother KR850 standard gauge ribber.
When the sponge bar goes bad, so will your knitting. Stitches may drop for no reason or the carriage might jam, getting its underside caught on needles at the wrong height. When my machines act up, the sponge bar is the first place I look.
Your needles can tell you how your sponge bar is doing. Depending on the machine, the needles will react differently when the bar starts to disintegrate.
When the foam is dead in a standard gauge machine, there is nothing to hold the needles down. They will pop up in their channels which can cause the carriage to jam and needles to bend.
When the foam is dead in a bulky machine, the needles become loose and sloppy. They don’t pop up like a standard gauge machine.
To visually check your bar’s condition, you will need a pusher to get it out. I like to use a bamboo spear like a chop stick. It’s long and won’t scratch any plastic. A screwdriver will also work.
From either side of your machine, locate the end of the sponge bar near the front of the machine.
Gently push with the stick until enough of the bar protrudes on the opposite side to be pulled by your hand.
As you remove the bar, notice that the metal side is up.
This is IMPORTANT! The bar must be installed with the metal side up.
Turn the bar over and look at the foam.
Is it flat or does the sponge material slowly expand? If flat, it is dead and needs to be replaced.
Here is a comparison of a dead sponge bar and one that still has some life left.
To reinstall the bar, begin at either side. With the metal side up, push down on the needles so the foam rides on top. Continue down the length of the bed, pushing down needles and sliding in the bar.
Next post, we’ll take apart and clean out an old sponge bar. Later in this series, we’ll make a new bar from commonly available sheet foam and fusible interfacing.
- How To Make A Knitting Machine Needle Retainer Sponge Bar Part 2: Cut and Glue Foam
- How To Take Apart A Brother Punch Card Knitting Machine
- How To Make A Knitting Machine Needle Retainer Sponge Bar Part 1: Remove The Old And Clean For New
- How To Make A Knitting Machine Needle Retainer Sponge Bar Part 3: Fuse Interfacing, Tape Ends, And Reinstall
- How To Install A Passap Duomatic 80 Racking Handle
July 14, 2008