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My First Mill

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  • My First Mill

    Well almost. My pre BP days. I bought this Sears Craftsman 18" X Y table back in 1992. I paid $222 shipped to my door.
    It wasn't the best but I needed to do some milling and thought this might be the answer. I found out pretty fast that you can't do much milling with it.
    Wood, plastic and soft materials like aluminum and brass if I was careful I could accomplish what I had to do. Steel, well with a good sharp end mill and cut of a few thou in depth and a slow feed I could get by until the MT2 and chuck drop out of the drill press spindle.

    A few months later I gout a BP and used this X Y for wood working and light stuff in my wood shop.
    It's been sitting around with hardly any use for years. Collecting dust, not rusty or anything just dusty and gummed up.
    I took it all apart and cleaned it yesterday. I had brief thoughts of stripping the cheap paint off of it and doing a little body work on the poor castings and putting a nice coat of paint on it. Also had thoughts of cleaning up the horribly rough dovetails but then decided that it's not going to give me any more accuracy on a drill press so I'm in the process of putting it back together.

    They really rip through these castings when they milled them out. Actually it almost acts as scarping to hold the oil.





    Notice the two gibbs. Stamped out of hot rolled sheet and blanchard ground on one side. I'm surprised the stay in place.
    When I get it all back together I'll set it on my surface plate and check it for height all the way around just out of curiosity.

    JL..............
    Last edited by JoeLee; 09-11-2019, 02:00 PM.

  • #2
    looks similar to the cheapy HF X-Y vise I used on my drill press as a "mill" for a couple of years, my guessing is that the Chinese just copied the Craftsman one. Lots of flaws, many of which you identified, but also including lack of thrust bearings for the lead screws and a jaw that lifts so bad it's like a 1930's cartoon of a lady and a mouse. I fixed a bunch of those flaws, including making new jibs and it did serviceable if slow mill work. Still use it for accurate hole positioning on the DP using the HF calipers I added to each axis.

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    • #3
      I think this one was made in Taiwan at the time. Yes, no thrust bearings on either of the screws but given the shallow DOC and force that this would be subjected to you really don't need thrust bearings. You can't hog with it that's for sure.

      No chip shield either to cover the in-feed screw when you move the saddle back. They even tell you in the manual to cover it with something to keep chips off the screw.

      Surprisingly the screws are accurate and do read accurately to the dials in .001. That's all you would really need for accurate hole locating for drilling.
      Now that it's clean again it does move pretty smooth in all directions. I doubt that re-cutting the dove tails and making new gibbs would make it any smoother.
      After all I'm at the mercy of the drill presses rigidity and bearing accuracy.

      JL.................

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      • #4
        I found that adding thrust bearings and new jibs made a huge difference in how much force was needed to get the table moving and how smoothly it did once it was moving. Well worth the effort. No dials of any use on mine, hence the digital calipers. Clearly a much less complete product than the Craftsman version, but it did only cost me $60 with a coupon!

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        • #5

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          • #6
            The above pics are on the thought of counterboring the end brackets out for a thrust washer.
            For some reason I couldn't add text to that post.

            Anyway, the issue would be the bore through the brackets. The size that fits the shaft is only about 3/8" in length. The rest of the hole is like over size rough cast.
            I would end up counterboring most of the shaft hole away for the thrust bearing and washers.

            Which leads to completely boring the hole out oversize and making bronze sleeves.

            JL............

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            • #7
              Sometimes just using the hardened steel thrust washers is enough to make the action slick by removing drag.McMaster has them down to 1/32" thick.

              That does look like one of the better quality X/Y vises.Are the hand wheels cast iron too or Aluminum?
              I just need one more tool,just one!

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              • #8
                I could make, harden and grind the thrust washers to any size / thickness I want.
                If I could end up with a total thickness of 1/8" or less with two washers and a bearing I could do it without having to over bore and sleeve the hole.
                That would leave me with about 5/16" or so of shaft bearing surface.

                JL..............

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                • #9
                  yeah, that doesn't sound like a lot of room - a steel or brass thrust washer would still help a bunch though. Not sure how your table works, but on mine the leadscrews are only captive at the handle end, so would bear against the bracket in both directions. If that's the case with yours, might be worth making a small thrust washer for the backside of that bracket, depending on what the leadscrew and bracket look like.

                  Here's the "Y" axis bracket
                  back

                  front


                  it did have just a brass thrust washer there for a while, but the thrust bearing made a noticeable improvement. Still a turd, but a nicer turd

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                  • #10
                    I was going to ask this but you already answered it for me.

                    It looks like you made a whole new front bracket. I don't need to do that.

                    I put the rest of this together this morning and fiddled with it a bit. The saddle moves freely in the center but when it gets close to the outer ends it starts to get sticky.
                    Even harder to reverse the direction until it get about half way in. I couldn't really find a happy medium in the gibb adjustment. It's probably a discrepancy in the width of the dovetail.
                    I didn't check but I will take a measurement.

                    On the thrust washer part...........

                    One thrust washer between each hand wheel on the table will work. The saddle screw is going to be a different story.

                    When the saddle is moved back to the operator the pulling force will be on the thrust bearings between the hand wheel and bracket. When moved away from the operator the pushing force is going to be against the back side of the bracket. So there will need to be two thrust bearings on that screw.
                    As is stands now I believe the pushing force is against the start of the screw thread and the bracket or the step in the shaft and the edge of the shaft hole. Not a good set up.
                    Probably one of the reasons the saddle moves easier in one direction than the other. This will be a good winter project.

                    PS: is your bearing exposed to swarf??? looks it in your picture.

                    JL................

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                    • #11
                      yup, this will show you why


                      both bearings are covered to prevent swarf falling on them, but a couple of squirts of oil and some use flushes out any crap that makes it in there.

                      the bearings on both sides make a great deal of difference, noticeable when the lead screw was bearing against the cartridge bearing vs. the thrust washer. that'll be part of the reason you find it harder going in one direction than the other, if the direction lines up.

                      getting harder to move the table at one or both extremes is either a poorly cut dovetail or a misalignment between the table and the leadscrew. My "Y" axis is harder to move at both extremes, so probably the dovetail. It does look like it's been gnawed at by a dovetail beaver.

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                      • #12
                        This is where the force is when the saddle is being moved back or away from the operator, I called it being pushed back. The load is between the end of the screw and the back of the mount.
                        I'm going to make a bronze washer to put in between there and see if that helps any.

                        Anyway....... for that screw I would have to put a thrust bearing on either side of the mount. Not a problem since there is plenty of thickness to work with.

                        The table screw has a hand wheel on each end so one thrust bearing per side will work there.

                        I'm sure the uneven and rough cut of the dovetails is the reason for the binding. Going to have to mill those parallel.

                        JL.................

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                        • #13
                          I measured the width of the dovetail on the base. It tapers from front to back about .005. I'm sure that accounts for the binding when the saddle is brought towards the operator.

                          I haven't checked the mating part. I'm going to have to clean them up on the mill. I hope they are 60 deg. and not some bastardized angle.

                          JL..........

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                          • #14
                            The other reason the saddle is binding at the front when reversed is the gibb is sliding back and forth about 1/16". After I took this thing apart I wondered how it even stayed in place with the edge of a screw contacting it at a 60 degree angle. It should really be pinned in place.

                            My KO Lee radial grinding fixture cross slide gibbs are pinned and the gibb screws are pointed. I may point the ones for this table. the point will bite in and keep the gibb from sliding.

                            JL...............

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                            • #15
                              Originally posted by wierdscience View Post
                              Sometimes just using the hardened steel thrust washers is enough to make the action slick by removing drag.McMaster has them down to 1/32" thick.

                              That does look like one of the better quality X/Y vises.Are the hand wheels cast iron too or Aluminum?
                              It probably looks like it's one of the better made ones because it's older. Yes the hand wheels are cast iron.

                              JL.....

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