I use nothing but but people powered machines either HC or Treadle. I have found that once a machine is properly cleaned I use sewing machine oil to keep it oiled. I also use tri-flow oil. Both are great products. However I will not mix them. A machine oiled with tri-flow will only be oiled with tri-flow. Likewise a machine oiled with sewing machine will only be oiled with machine oil. This being said once a machine is properly cleaned I can't tell the difference between which one is lubed with machine oil or tri-flow. They key is to keep the machines oiled as needed and you should have no problems.
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