Piston vs Cylinder wall.

Discussion in 'General Engine Discussion' started by jacobball2000, Jan 13, 2019.

Help Support HMEM by donating:

  1. Jan 18, 2019 #21

    Brian Rupnow

    Brian Rupnow

    Brian Rupnow

    Well-Known Member Project of the Month Winner

    Joined:
    May 23, 2008
    Messages:
    11,667
    Likes Received:
    4,224
    The best possible combination is a cast iron piston and a cast iron cylinder. There is enough free graphite in cast iron to let the two surfaces slide over each other without galling. Never use steel on steel. For 1/2" bore you don't need any rings. Lap the piston into the cylinder to make an air-tight seal. Leave a cylinder wall of 0.060" thick. Make the cylinder first. Make the piston close to size but not quite. Use a sanding strip and work the piston down until it just starts to slid into the cylinder but will not slide in. Coat the piston with 600 grit carborundum paste or diamond paste and with one part turning slowly in the lathe, work the other part into it very slowly until you have a complete fit from end to end.
     
    metalmudler likes this.
  2. Jan 19, 2019 #22

    metalmudler

    metalmudler

    metalmudler

    Active Member HMEM Supporter

    Joined:
    Jan 9, 2013
    Messages:
    40
    Likes Received:
    13
    Gender:
    Male
    Occupation:
    Refrigeration & A/C
    Location:
    Sydney AUSTRALIA
    Hi Brian,
    I bought some diamond paste. I am quite hesitant to use it though. From my understanding small hard granules like zircon embed themselves into softer materials when they are kind of pushed into them. I feel I have no way of effectively cleaning them out of a bore surface, or off a wearing component so i try to use softer abrasives so as not to accelerate premature wear. Am I being ridiculous?
     

Share This Page