Announcement

Collapse
No announcement yet.

Drilling SS tube without burrs

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Drilling SS tube without burrs

    I need to drill a bunch of .04 holes in 1/4" SS tube, but I don't want burrs on the inside. I'll be doing this on the CNC

    Option 1: Drill undersize and then finish with a little circular loop using a little 1/32 end mill.

    Option 2: Drill to size, and put an aluminum plug on the inside

    Option 3: Drill to size, and try to clean up the burrs on the inside somehow.

    Option 4: ????

  • #2
    Drill it under size and then use a boring bar to finish it from the inside out, or drill normal and run a 1/4''reamer down the tube. I didn't say it would be fast or easy though .

    Steve

    Comment


    • #3
      They have these nifty de-burring tools for CNC machines. I see them advertised in the banners all the time. If you have a tool changer, you might look at investing in one of these tools. It has a carbide insert and plunges in to the freshly drilled hole. As it is withdrawn, it is supposed to deburr. No idea if they actually work worth a darn ... but it's a thought.

      Comment


      • #4
        After I posted this, I realized that .04 holes are really small. Anyway, this is what I did:

        1) drill the holes
        2) find a rod with an OD slightly less than the ID of the tube I drilled, and jammed it thru. Some of the burrs popped off, and some up them got pushed back up into the holes
        3) push the burrs out of the drilled holes with the back end of the drill bit
        4) repeat step 2, but from the other end
        5) wrap some sandpaper around the rod, and jam it thru the tube to sand off the remaining burrs.

        Comment


        • #5
          The burr forms for lack of support underneath. On some materials, it helps to slow the feed just before it pops through. On stainless, I'd worry that could work harden it, especially with these small holes.

          A small piece like this could be a candidate for the ice frozen inside approach.

          Cheers,

          BW
          ---------------------------------------------------

          http://www.cnccookbook.com/index.htm
          Try G-Wizard Machinist's Calculator for free:
          http://www.cnccookbook.com/CCGWizard.html

          Comment


          • #6
            You might try filling the tubes with some of that low-temperature fixturing alloy (Cerrosafe, or similar).
            ----------
            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

            Comment


            • #7
              How would having ice in the tube (bringing the temperature of the material much lower than normal) affect the work hardening characteristics?
              Any products mentioned in my posts have been endorsed by their manufacturer.

              Comment


              • #8
                I'm not sure it would. In this case, it would be used to support the backside of the work during the drilling operation. Although I have to say, I'm not sure how long it would stay frozen. One of the low temp alloys might be better.

                Originally posted by winchman
                How would having ice in the tube (bringing the temperature of the material much lower than normal) affect the work hardening characteristics?
                Last edited by RKW; 06-16-2010, 01:25 PM.
                "Work hard. Tell everyone everything you know. Close a deal with a handshake. Have fun!"

                -- Harold "Doc" Edgerton

                Comment


                • #9
                  Internal burrs

                  Originally posted by beanbag
                  I need to drill a bunch of .04 holes in 1/4" SS tube, but I don't want burrs on the inside. I'll be doing this on the CNC



                  Option 2: Drill to size, and put an aluminum plug on the inside


                  I'd vote for option #2. You could even use hardwood dowel stock and it should work.
                  Jim (KB4IVH)

                  Only fools abuse their tools.

                  Comment


                  • #10
                    The tube I was drilling was about .2 ID and 12" long, with a row of about 30 holes. I didn't use the dowel approach because I was worried that if any burrs formed at all, it would cause the dowel to get stuck inside the rod.

                    Comment

                    Working...
                    X