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where to buy air bearing spindle for T&C

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  • where to buy air bearing spindle for T&C

    I am intrigued by sharpening my own end mills. Where might I start to look for the air bearing spindle attachment? It might not be practical but I would like to at least check it out. Thank you in advance for your help.
    How to become a millionaire: Start out with 10 million and take up machining as a hobby!

  • #2
    Maybe you want a Block-Head? But you'd have to sell all your tools to afford one.
    Do you want the air bearing for the work head or the wheel head?
    I assume the work head. But many commercial T&C grinders do have tapered roller bearings in them. Only for very delicate work (reamers) an air bearing is a advisable option (doesn't mean it is bad for other applications).

    Nick

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    • #3
      I wanted it to hold the end mill to grind the flutes.
      How to become a millionaire: Start out with 10 million and take up machining as a hobby!

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      • #4
        I wanted it to hold the end mill to grind the flutes.
        My T&C grinder has relatively huge tapered bearings. It accepts SK50 (you call that CAT50). That works great, even that I do have to move the whole table that is 1.1m long.


        Nick

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        • #5
          Originally posted by Black Forest
          I wanted it to hold the end mill to grind the flutes.
          you want an air bearing, they'll be expensive, a quick google found this,
          http://www.google.ca/imgres?imgurl=h...26tbs%3Disch:1

          yup, they're expensive. not sure if it was HSM, but one of the mags had an diy article
          .

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          • #6
            There is a Yahoo tool grinding group
            http://groups.yahoo.com/group/ToolGrinding/
            that discuss things like this and probably have plans for a DIY version.

            Michael

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            • #7
              The Shop Wisdome of Philip Duclose book has the plans for building the "Floating " End Mill Sharpener. It uses a home built air bearing set up. I plan on building it as soon as I come up with the material.
              Mel
              _____________________________________________

              I would rather have tools that I never use, than not have a tool I need.

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              • #8
                Between centres

                Originally posted by MuellerNick
                Maybe you want a Block-Head? But you'd have to sell all your tools to afford one.
                Do you want the air bearing for the work head or the wheel head?
                I assume the work head. But many commercial T&C grinders do have tapered roller bearings in them. Only for very delicate work (reamers) an air bearing is a advisable option (doesn't mean it is bad for other applications).
                Nick
                Nick.

                I'd prefer to grind reamers between centres.

                I think the OP should have asked if an air spindle was necessary - its not.

                I have two T&C grinders - one has an air spindle the other not. The air-spindle is nice - very nice - but the other is very good as well.

                I have used a "Spindexer" to do the job and providing its a good "Spindexer" it will do the job quite well.

                Size of the diameter is not an issue with re-ground end-mills but minimising the taper is.

                The concentricity of the collet in the T&C grinder is an issue as it is the means of keeping the cutting edges concentric with the end-mill shank (that is held in the mill collet/s).

                In an ideal world both the bore of the collet in the mill and the collet in the grinder should be perfect - but the chances are that they won't be. Both together may either cancel each other out or add to each other - or anywhere in between.

                So its best to get the grinder collets as accurate as possible.

                The end mill is ground by passing the wheel past the cutter or the cutter past the wheel.

                One way of passing the cutter past the wheel is usually achieved by locking the table "X" travel and having the work-head spindle both rotate and advance axially so as to follow the end milling cutter spiral. This is achieved by using a "finger" which locates on the cutter spiral. In this method the finger is located either on the table or the work-head.

                Another way is to lock the axial travel of the work-head spindle (while still allowing it to rotate) and using the finger as previously, rotate the work-head spindle while advancing and retracting the (now unlocked) grinder table. In this method the finger is located on the grinding head.

                "Spindexer" and non-air spindle:


                Non-air spindle:


                Air spindle/quill:


                The air spindle/quill is very accurate and is very easy to use as it literally floats on a film of air - it is the best of the three.

                The non-air spindle is excellent as well and marginally behind the air quill.

                The "Spindexer" is a little "heavier" but surprising good never the less. This is one that I bought from ArcEuroTrade (UK).

                The grinders are the only machines that I use my C5 collets as I prefer ER-32 collets. I also bought the John Stevenson designed C5>ER-32 adaptor from ArcEuroTrade as I can use my ER-32 collets in my C5 spindles when it suits. There has to be some error - very small - in the adaptor - so I choose to use the C5 collets - which are very good.

                What you want for a specific process or job is not always what you need.

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                • #9
                  Originally posted by lugnut
                  The Shop Wisdome of Philip Duclose book has the plans for building the "Floating " End Mill Sharpener. It uses a home built air bearing set up.
                  Lane built the Phil Duclos air bearing, and did a superb job, as usual. If you click on his .sig link, you can see pictures of it.

                  From what I've heard, the hard part is getting the bore perfectly straight (the diameter doesn't matter, but the straightness and clearance are critical).
                  "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

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                  • #10
                    Lane built the Phil Duclos air bearing,
                    Lane did indeed build the Duclos air bearing, but even with his impressive machining skills, he said it was a royal pain to get it to that point where it had that "float".

                    I have a Cuttermaster with its air bearing, and its is very sensitive to dirt/dust, with the slightest contamination making it "draggy", so I can imagine trying to machine those tolerances would/could be a pain.
                    If everything seems to be going well, you have obviously overlooked something........

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                    • #11
                      Air quill

                      Lazlo.

                      Not only super size but super finish and super straight. The finish on my air quill spindle seems to be ground and lapped hard-chrome and the bore of the (aluminium?) work-head is lapped.

                      The clearances are that close to zero that it doesn't matter. I never leave my quill in the work-head. Putting it back is a work of art as it will "grab" if it is the slightest bit off-line when re-inserting it.

                      The bore and spindle/quill have to be dead on size as well as dead round and dead straight.

                      I put an in-line oiler in my airline and use "3-in-1" (same as sewing machine) oil in mine. Any heavier or larger quantities of oil makes the quill "drag".

                      The co-efficient of friction is so low that if the head and quill are tilted about 1/8" per foot (1:96) the quill will start to slide and accelerate. And that can be a PITA as I've had it "get away" a couple of times.









                      http://i200.photobucket.com/albums/a...Air-quill5.jpg

                      http://i200.photobucket.com/albums/a...Air-quill6.jpg

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                      • #12
                        I wonder how much it would cost to make a set of those castings...

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                        • #13
                          Air quills - or not?

                          Originally posted by Bill Pace
                          Lane did indeed build the Duclos air bearing, but even with his impressive machining skills, he said it was a royal pain to get it to that point where it had that "float".

                          I have a Cuttermaster with its air bearing, and its is very sensitive to dirt/dust, with the slightest contamination making it "draggy", so I can imagine trying to machine those tolerances would/could be a pain.
                          Bill,

                          that agrees with my "take" as well.

                          The air-quill can be a PITA and I rarely use it.

                          I prefer my other "non-air" quill as it has a "firmer" "feel" and has to be driven where-as the air-quill has a mind of it own at other than horizontal. As I said previously, my "Spindexer" works pretty well as well.

                          When I was grinding milling cutters etc. on a Cincinnati T&C grinder there was no quill that moved axially in the work-head (there was but it was rarely used) as we gripped the end milling cutter in the work-head (the spindle could rotate but not move axially) and so we used our right hand to rotate the spindle and cutter while we moved the table axially ("X"?) with out left hand. So there was no sliding quill at all.

                          We did a lot of "between centres" work for special tools etc. as well as reamers and with slab milling cutters and side and face cutters on mandrels etc.

                          A T&C grinder is a very versatile machine as it functions pretty well as a surface grinder and as a cylindrical grinder as well.

                          A surface grinder can function pretty well as a T&C grinder (but not really as a cylindrical grinder) as well.

                          I am not the least bit surprised at the difficulty of making a good air quill - and if someone of Lane's calibre and skill (and patience??) levels was "pushed" that hard, it will give an indication of just how hard it would be to make one!!

                          If a push came to a shove, I'd get by with a good "Spindexer" and a set of shop-made centres and use either my T&C grinders or my surface grinder.

                          I have to say that the really best effort I've seen here or just about any place else for a shop-made end-mill T&C grinder is Evan's mill on which he sharpened end mills by CNC - no "fingers" etc. needed - a top job.

                          I hope that Evan reads this and provides a link to that set-up.

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                          • #14
                            Originally posted by oldtiffie
                            The co-efficient of friction is so low that if the head and quill are tilted about 1/8" per foot (1:96) the quill will start to slide and accelerate. And that can be a PITA as I've had it "get away" a couple of times.
                            Sounds like a quick trip to the hardware and appliance store at the Uluru Mall for a box of multi-sized O-rings is in order, mate. One on the shaft at each side of the block should arrest the shaft until you're ready to grind.

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                            • #15
                              Ring

                              Dennis.

                              No use at Uluru mate. They use all the "O" rings as intra-uterine contraceptive devices.
                              http://en.wikipedia.org/wiki/Vaginal_ring

                              The air that escapes from between the work-head and the quill is pretty effective - but the "grindings" don't seem to do much harm.

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