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  • Hardinge Horizontal Mill

    Hello,

    After making a new power feed shaft for my mill (the shaft was bent when I bought it) and replacing the power feed shaft bearings, I was attempting to do some milling on my Hardinge horizontal mill over the weekend. So, I used a 5c collet to hold an end mill, set everything up, and attempted to mill about 0.010 off of some metal stock. I had the powerfeed set to 0.001 movement of the table per revolution of the spindle, was using a 3/4" 4 fluted end mill, at about 110 RPM. (I didn't compute any speeds and feeds, since this was the first attempt and I wanted to be careful...so I set everything rather slow.) Everything was going fine until I noticed that the endmill was slowly being pulled out of the collet and futher into the work.

    Should I make a dedicated endmill holder or am I doing something wrong? The 5c collets are brand new...from Grizzly.

    Thanks,

    Brian
    There are only 10 types of people in the world: Those who understand binary and those who don't.

  • #2
    Yes make or buy an endmill holder , if that small cut pulls the endmill out you will never get any milling done.

    If you have long endmills you can put a spot weld on the shank and load the endmill from the back side of the collet so it cant pull out. Thats kind of cheasy but it works.

    Im not a big fan of milling with collets, people do it all the time but its just not the best way to hold an endmill.

    For some reason you are not getting the draw bar tight, are the threads bottomed out or something? can you add a little spacer to make it pull harder? You should be able to mill a small cut like that easy.
    Last edited by tattoomike68; 10-09-2007, 03:19 PM.

    Comment


    • #3
      Originally posted by tattoomike68
      Yes make or buy an endmill holder , if that small cut pulls the endmill out you will never get any milling done.

      If you have long endmills you can put a spot weld on the shank and load the endmill from the back side of the collet so it cant pull out. Thats kind of cheasy but it works.

      Im not a big fan of milling with collets, people do it all the time but its just not the best way to hold an endmill.

      For some reason you are not getting the draw bar tight, are the threads bottomed out or something? can you add a little spacer to make it pull harder? You should be able to mill a small cut like that easy.
      I got the drawbar hand-tight....though, that may not be tight enough. Is it possible to overtighten 5c collets? Maybe I should make up some sort of wrench to tighten the drawbar?

      I don't know where I would put a spacer.

      The spot weld idea is interesting...as a short term solution. But, my endmills aren't long enough.

      Making an endmill holder would be a good idea. However, my P&W lathe doesn't have change gears....yet. I suppose I could thread it on my Sherline. I would also have to cut the taper on my sherline since my P&W doesn't have a working taper attachment...yet. <Sigh.> Making 0.020 to 0.050 cuts on my P&W really can spoil a person. I think I'll take this route.

      Thanks,

      Brian
      There are only 10 types of people in the world: Those who understand binary and those who don't.

      Comment


      • #4
        Hand tight is not near enough for milling. You might just get away with making a draw bar or some wrench to give it a little snugging.

        I have a little rule with torquing a draw bar. I use two fingers on the wrench and get it as tight as I can with 2 fingers. That way im not pulling the threads on my draw bar. If I can bust it with 2 fingers it was no good anyway.

        good luck I hope you get it cutting soon.

        Comment


        • #5
          Originally posted by tattoomike68
          Hand tight is not near enough for milling. You might just get away with making a draw bar or some wrench to give it a little snugging.

          I have a little rule with torquing a draw bar. I use two fingers on the wrench and get it as tight as I can with 2 fingers. That way im not pulling the threads on my draw bar. If I can bust it with 2 fingers it was no good anyway.

          good luck I hope you get it cutting soon.
          Thanks for the info! I'll see about making a wrench first.

          Regards,

          Brian
          There are only 10 types of people in the world: Those who understand binary and those who don't.

          Comment


          • #6
            Rif,

            Quote

            "about 0.010 off of some metal stock. I had the powerfeed set to 0.001"

            You're not cutting it off, you're rubbing it off.
            You should be making chips, not dust with that mill.
            That will wear more off the mill, than the material.

            I'd say the collet needs use of a wrench, the mill a bit more rpm,
            and feed.

            It should take at LEAST a couple thou feed per tooth (minimum) of the mill.
            That's real conservative too.

            Don't be afraid to tighten her up. That goes for the job too!

            Be sure the draw bar isn't bottomed out on the endmill shank.

            Kap

            P.S.

            That's what I heard in a serious chewing out
            when I was a new apprentice boy!

            Comment


            • #7
              Look in the manual and see what the factory tightening wrench looks like. Then make one similar in size.

              The Grizzly collet isn't helping the situation either.

              Comment


              • #8
                i've found the cheap collets can be way off, not always, but the can be. if the collet isn't very close to the cutter shank's dia, its gripping it by only a small surface area. Is the mill spindle 5c or are you using an adapter? if Hardinge thought enough of 5c's to put them on a mill, then i';d guess the collet's the problem.

                how about some pics of the mill?
                .

                Comment


                • #9
                  i have a question, and remember i am an untrained amateur and i didn't stay at a Holiday Inn Express last night.
                  how are you SUPPOSED to hold an endmill?
                  my mill has a B&S No. 9 taper, so i have some collets that i use to hold endmills with 1/2" shanks. if i am not supposed to use a collet, how should i hold the endmill? i never gave it much thought before because i always see mentions of folks' mills taking 5C or R8 or whatever collets, and i just assumed you used an appropriately sized collet to hold the endmill.

                  andy b.
                  The danger is not that computers will come to think like men - but that men will come to think like computers. - some guy on another forum not dedicated to machining

                  Comment


                  • #10
                    andy, collet or endmill holder. a lot of guys prefer the end mill holder because the helix of the endmill creates a force that wants to pull it down and out of the spindle. imo, using hardingle collets (no, i didn't buy them new) i've not had much trouble with them pulling out, but I do agree the end mill holder is more solid. The thing with endmill holders is there has to be a bit of clearance so the cutter is being spun slightly eccentric. I haven't quantified this, just figured it might not be good with smaller dia cutters. A common mill collet is the R8, a little smaller than 5C (they don't' come in 1" size) and the ID that grips the shank is longer than for 5c. struck me as odd that hardinge would have used 5C for a milling spindle instead of R8 but there's lots i don't know
                    .

                    Comment


                    • #11
                      Ok..... it's a small mill. Nice. I have a similar sized mill. Make yours work hard..... I do.


                      1) Collets do that, (donning flame suit) primarily becuse they are springy, and have a relatively short length of grip. But I bet you didn't get it tight, if that tiny cut loosened it up. No way it should have.

                      2) You do NOT have to have a taper attachment to make a taper. That's what the compound is for. I have made a number of MT3 taper items on the Logan with no taper attachment. Several arbors for the mill, a collet closer for the lathe, accessories for other things. Set the compound up.

                      The lathe you mention should have a compound travel considerably longer than mine, ought to be a piece of cake. Seriously. All you need is a good indicator, and some sort of "model" taper. You CAN wing it with a piece of scrap, and try the fit until right, also, but it's the hard way to go.

                      3) what you REALLY need, assuming your mill is a TM UM and has an overarm, is to make some arbors, and get some real horizontal milling cutters. That will get some work done.
                      1601

                      Keep eye on ball.
                      Hashim Khan

                      Comment


                      • #12
                        Originally posted by Mcgyver
                        andy, collet or endmill holder. a lot of guys prefer the end mill holder because the helix of the endmill creates a force that wants to pull it down and out of the spindle. imo, using hardingle collets (no, i didn't buy them new) i've not had much trouble with them pulling out, but I do agree the end mill holder is more solid. The thing with endmill holders is there has to be a bit of clearance so the cutter is being spun slightly eccentric. I haven't quantified this, just figured it might not be good with smaller dia cutters.
                        oops.
                        so it seems this is an endmill holder:
                        http://cgi.ebay.com/MT-2-ENDMILL-HOL...mZ260169057686

                        i am embarrassed to admit i have several of these in some boxes of stuff that came with the mill. i just thought they were some funky holder for something. i never thought to stick an endmill in one. boy am i a dufus.

                        andy b.
                        The danger is not that computers will come to think like men - but that men will come to think like computers. - some guy on another forum not dedicated to machining

                        Comment


                        • #13
                          Originally posted by DR
                          Look in the manual and see what the factory tightening wrench looks like. Then make one similar in size.

                          The Grizzly collet isn't helping the situation either.
                          I didn't remember seeing a wrench in the manual...maybe I missed it. I'll check again and if I don'tfind one, I have an idea as to what it needs to look like.

                          Thanks,

                          Brian
                          There are only 10 types of people in the world: Those who understand binary and those who don't.

                          Comment


                          • #14
                            Originally posted by Mcgyver
                            i've found the cheap collets can be way off, not always, but the can be. if the collet isn't very close to the cutter shank's dia, its gripping it by only a small surface area. Is the mill spindle 5c or are you using an adapter? if Hardinge thought enough of 5c's to put them on a mill, then i';d guess the collet's the problem.

                            how about some pics of the mill?
                            It is 5c. Here is a picture of a similar mill. The difference is that my paint is poor and mine doesn't have the cooling system.

                            http://groups.yahoo.com/group/Hardinge-Mill/

                            Brian
                            There are only 10 types of people in the world: Those who understand binary and those who don't.

                            Comment


                            • #15
                              Originally posted by J Tiers
                              Ok..... it's a small mill. Nice. I have a similar sized mill. Make yours work hard..... I do.


                              1) Collets do that, (donning flame suit) primarily becuse they are springy, and have a relatively short length of grip. But I bet you didn't get it tight, if that tiny cut loosened it up. No way it should have.

                              2) You do NOT have to have a taper attachment to make a taper. That's what the compound is for. I have made a number of MT3 taper items on the Logan with no taper attachment. Several arbors for the mill, a collet closer for the lathe, accessories for other things. Set the compound up.

                              The lathe you mention should have a compound travel considerably longer than mine, ought to be a piece of cake. Seriously. All you need is a good indicator, and some sort of "model" taper. You CAN wing it with a piece of scrap, and try the fit until right, also, but it's the hard way to go.

                              3) what you REALLY need, assuming your mill is a TM UM and has an overarm, is to make some arbors, and get some real horizontal milling cutters. That will get some work done.
                              Yeah, I probably didn't have the collets tight enough. I'll make the wrench some night, this week, and try again.

                              Actually, my P&W lathe doesn't have a compound. It was made somewhere from 1893 to 1903 and uses a rise-and-fall cross slide. I have a bid, on e-bay, for a compound attachment for another antique lathe that may work. On the other hand, my Sherline lathe, has a compound attachment and I could use that....it's just that it takes forever to cut steel on that little fella.

                              UPDATE: I have been outbid on the compound and I am not going to make any other bids on it. The compound was for a Hjorth lathe and I don't know if it would be able to be used anyhow. I also figure that any body else bidding may just have a Hjorth lathe and it would be better if they had it anyhow.

                              I have 2 arbors, for the mill. But, I haven't gotten any horizontal milling cutters yet. I suppose I should put them on my shopping list.

                              Regards,

                              Brian
                              Last edited by Rif; 10-09-2007, 11:33 PM.
                              There are only 10 types of people in the world: Those who understand binary and those who don't.

                              Comment

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