No announcement yet.

Machining Bearings

  • Filter
  • Time
  • Show
Clear All
new posts

  • Machining Bearings

    I purchased some sleeve bearings that require a small amount of boring out to fit an oddball shaft (slightly over 0.500 inches diameter).

    The bearing material is not solid; it is sintered (?), I think. It resembles an "Oilite" bearing (porosities to hold lubricant) and may well be although the material was not presented to me as such.

    I tried using a boring bar. Got it opened out but the machined surface looks smeared. Is this still a satisfactory bearing? Would oil still percolate through or has machining blocked the spaces? If still useful how would it be lubricated?

    Finally, how can I machine it to obtain a proper surface?

  • #2
    as the story goes, ideally they are not supposed to be machined....if machining is required, use a razor sharp tool....hss well honed to avoid smearing. If smeared, well, maybe they'll work...fairly inexpensive to try again though if you want

    what was there before?


    • #3
      And try to take as deep a cut as you can, i.e., try to do it all at once. I found that if I tried to sneak up on the final dimension with light cuts it would tend to smear more.
      Try to make a living, not a killing. -- Utah Phillips
      Don't believe everything you know. -- Bumper sticker
      Everybody is ignorant, only on different subjects. -- Will Rogers
      There are lots of people who mistake their imagination for their memory. - Josh Billings
      Law of Logical Argument - Anything is possible if you don't know what you are talking about.
      Don't own anything you have to feed or paint. - Hood River Blackie


      • #4
        Actually they are supposed to be bored or reamed to size after being pressed in as they will be undersize.

        What kind of boring bar were you using? This is the time for a nice super sharp HSS bar.


        • #5
          Yes, sharp tooling with lots of clearance on all angles, some rounding of the nose but not much, rigid setup with play well controlled, and hit the required size in one go. Blow the swarf with air constantly. That's what works for me anyway. Hmm, it has been awhile since I did that.
          I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-


          • #6
            I've done it many times with a freshly sharpened bit, and the bearings worked fine. I was only removing several thousandths to get a free-running clearance with no noticeable play while truing the bearing ID to the other features on the part. Sometimes I could get the result I wanted with just a second pass of the last tool setting after a test fit of the shaft. The chips were like fine powder.

            The first one or two I tried had some smearing, but I soon learned how to cure that.
            Last edited by winchman; 08-30-2010, 01:59 AM.
            Any products mentioned in my posts have been endorsed by their manufacturer.


            • #7

              @McGuyver: Replacing the same type of bearing; was surprised that the shaft wasn't just a plain half inch. Proprietary, I guess.

              Sounds like razor-sharp hss is the way to go.

              Thanks all.


              • #8
                Bore out are ream out dont worry it will still oil.Been doing this mess 40 + years boring out a oilite bushing does not hurt it , it will still work jus fine . People worry to much about the littke things that dont matter.
                Every Mans Work Is A Portrait of Him Self