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  • Originally posted by reggie_obe View Post

    I thought you were a big proponent of owning a Hoyer lift or similar? Eliminates the the gift that lasts a lifetime, a herniated disc.
    What's a "Hoyer lift"?

    If it takes any floor space, the way an engine hoist does, it's not a "go" in the shop here. I want an overhead track and chain hoist.... one in the shop, and one in the shed. I have the parts for the shop version, but have not put it up pending a re-arrangement and expansion.

    The bed weighs not a great deal more than I have been lifting for my daily workout. But it weighs probably as much as me, and I know I cannot lift that much in the way needed to put it on the bench. So I lifted each end separately, which was easy.

    No, I do not want the lifetime gift.... one reason for the strengthening routine.





    CNC machines only go through the motions

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    • Originally posted by J Tiers View Post

      What's a "Hoyer lift"?
      A hydraulic lift used in hospitals and nursing homes for lifting patients. They have wide straps forming a seat. They will lift somewhere between 300-500 lbs depending on the model and are light weight and easy to store. A friend has a couple of them and uses them for lifting rider mowers when working on them. I have a engine hoist but wouldn't mind having one of the hoyer lifts around just for convenience, they are so much more compact and easy to maneuver.

      Not sure but they may fold up for storage, don't quote me on that.

      PS My friend got both of his at the junkyard. If the "seat" straps get worn or similar they just scrap them.
      Last edited by Sparky_NY; 03-16-2021, 03:54 PM.

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      • Originally posted by J Tiers View Post
        it looks like I will not have to remove 0.004"........

        Probably more like 0.006"! It is do-able, and there is time to do it, it's already sat several years, and I am a little afraid of what a grinding house might do to it!.
        You might be well positioned, then. If your straightedge can bridge to relatively unworn spots on the top, you can identify the lowest points by location and amount. Supposing you find .004 at the worst spot. So you shovel off .004 in pads at the four corners since you can verify that with a mic. Then you have, nominally, a two hump camel and you can work the humps so you've got flats end to end and equal mic dimensions at the corners.

        Sorry, I know it's a lot harder to implement than to suggest.
        .
        "People will occasionally stumble over the truth, but most of the time they will pick themselves up and carry on" : Winston Churchill

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        • Originally posted by J Tiers View Post
          it looks like I will not have to remove 0.004"........

          Probably more like 0.006"! It is do-able, and there is time to do it, it's already sat several years, and I am a little afraid of what a grinding house might do to it!.
          At .006 I would start the job with 2nd cut files. It'll still take a while.
          25 miles north of Buffalo NY, USA

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          • Originally posted by J Tiers View Post

            The bed weighs not a great deal more than I have been lifting for my daily workout. But it weighs probably as much as me, and I know I cannot lift that much in the way needed to put it on the bench. So I lifted each end separately, which was easy.
            I don't work out at all, but I've spent a lifetime in heavy fabrication and repair.
            My lathe (minus motor) is around 600 lbs. That is all in a day's work for me.
            I have to move heavy stuff to do my job when it comes to welding in a semi truck shop.
            25 miles north of Buffalo NY, USA

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            • Originally posted by TGTool View Post

              You might be well positioned, then. If your straightedge can bridge to relatively unworn spots on the top, you can identify the lowest points by location and amount. Supposing you find .004 at the worst spot. So you shovel off .004 in pads at the four corners since you can verify that with a mic. Then you have, nominally, a two hump camel and you can work the humps so you've got flats end to end and equal mic dimensions at the corners.

              Sorry, I know it's a lot harder to implement than to suggest.
              Not really, it's about how I propose to go at it. The 4 pads is more of an issue, since you need a reference surface to measure from, and all the surfaces other than the V are bad. But, yes, basic two humped camel, and work.
              CNC machines only go through the motions

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              • Originally posted by Sparky_NY View Post

                A hydraulic lift used in hospitals and nursing homes for lifting patients. They have wide straps forming a seat. They will lift somewhere between 300-500 lbs depending on the model and are light weight and easy to store. A friend has a couple of them and uses them for lifting rider mowers when working on them. I have a engine hoist but wouldn't mind having one of the hoyer lifts around just for convenience, they are so much more compact and easy to maneuver.

                Not sure but they may fold up for storage, don't quote me on that.

                PS My friend got both of his at the junkyard. If the "seat" straps get worn or similar they just scrap them.
                Thanks. It's partly the storage space, but much more the room to maneuver the thing in the actual shop area. Shop is "compact", which I like (it is in the old coal bin) but it does have disadvantages. In order to fit the Rivett in on its cabinet base, I have to make more room by pushing the walls outward. That has been an ongoing issue of layout, not solved yet.
                CNC machines only go through the motions

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                • Originally posted by J Tiers View Post

                  Not really, it's about how I propose to go at it. The 4 pads is more of an issue, since you need a reference surface to measure from, and all the surfaces other than the V are bad. But, yes, basic two humped camel, and work.
                  Maybe a sled for the V to hold an indicator is the last resort. If you indicated to the spot under the headstock as zero, you'd have a way to gauge how the scraping is doing on a smaller pad at the headstock end. Same reading at the tailstock end. It always annoys me to have to spend much time making a one shot tool to do something else, but sometimes it happens and I usually get over it.
                  .
                  "People will occasionally stumble over the truth, but most of the time they will pick themselves up and carry on" : Winston Churchill

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                  • The sled?

                    Look at the pics...... I made a Kingway type indicator holder, which is adaptable for almost anything. I use that a lot. It is how I developed the 6 thou measurement. Problem being that of course one needs reference surfaces for it (or for any "sled"). Then you have to use an external one such as the straightedge, which makes it similar to the planekator.

                    For the V, it is so narrow that tiny errors would cause big issues if used alone as the reference. Then to avoid that another surface is needed..

                    Straightedge is a bit shorter than the bed, so I'll have to slightly extend the spotting, and I cannot bridge it from end to end. But it will get the job done.
                    Last edited by J Tiers; 03-17-2021, 12:47 AM.
                    CNC machines only go through the motions

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                    • Got some time to measure again, and got a surprise!

                      The majority of the across-bed wear is on the back side. The front side, with the three surfaces and the dovetail seems to be worn only one or two thou, maybe less, measuring with the Kingway device riding in the V of the top, which is apparently OK.

                      These conclusions pass the "smell test", since nothing actually runs in the V but the tailstock, which is generally moved far far less often than the carriage. And it makes sense that the smaller wear surface might wear several times more than the very large area of the side ways and dovetail.

                      I'm not getting too excited yet, but it appears that the thing may actually not be really disgusting as far as the bed is concerned. It will still need scraped, but may not require a ridiculous amount on the "hard part".

                      I should note that the reference to the V is not absolute. I have the Kingway cylinder in the V, but the slider foot is running on the top. That seems to have a fairly small effect, but not zero.
                      CNC machines only go through the motions

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                      • Have not gotten much done on the 608 bed, but did come up with an interesting observation.

                        Most seem to think that the 608 beds were simply ground, and then flaked for oil retention. As I look at this one, I think that the pattern I see looks like scraping under the flaking. I'll try to get a decent picture.

                        I do not see the type of surface I'd expect from grinding alone. I noticed it after I had used a burr file to cut down the various "dings" and resulting bumps, with a quick pass of a fine stone over the surface afterward, to remove whatever might be left.

                        I'm thinking that if they were ground, and that seems reasonable, that they then may have been scraped to "tweak performance", and finally flaked for oil retention, as well as the coolness of the overall effect.

                        CNC machines only go through the motions

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                        • Here's what I was talking about. These surfaces are at the headstock end of the bed, on the side ways, where nothing ever moved against the surface. I have not done anything to the surface other than clean it, and use a burr-file on some dings. The underlying surface does not look like a ground surface, but rather like a scraped surface.

                          You can see the "Nike swoosh" flaking, but under that appears to be a surface which is not ground, but scraped.



                          CNC machines only go through the motions

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                          • I'm not adding ANY new content to this thread.

                            From now on, I am adding posts to this new thread, which has a more descriptive title:

                            https://bbs.homeshopmachinist.net/fo...tt-608-rebuild
                            CNC machines only go through the motions

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