I purchased a used Kenmore portable washing machine that was missing the knob for selecting the cycles so I went to the local parts dept. to order one and found out that they wanted $33 so I decided to see if I could improvise something.
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The wife and I did a little brain-storming and decided that a spool for sewing thread would work as the splines would engage the "spurs" protruding from the base knob (sorry I should have taken more pics) so the spool was cut down to fit the threaded spindle so that when the spindle is pushed in to allow adjusting the cycle settings, the spindle and the cut off spool would be flush with each other. I then decided that it needed something so that I could grip it better, so my wife came up with a bottle cap from a juice bottle that fit fairly well though loosely so I glued it on with hot glue. When the hot glue cooled I put hot glue in the spindle hole of the spool till it was about half full and then pushed it on to the spindle of the washing machine and held it there 'till the glue firmed up.