Announcement

Collapse
No announcement yet.

A bevy of scraping question

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

  • #16
    That is one cool tool, anyone recall the issue it was in the magazine?

    Comment


    • #17
      It was actually a four part series by Michael Ward. I was going to post about those articles, but J Tiers and Mcgyver beat me to it. And I did not have the nice photos that Mcgyver posted so his post was better than what I would have been able to do. I did look up the issues: they were in:

      Part 1 - Home Shop Machinist, Mar/Apr 2019
      Part 2 - Home Shop Machinist, May/Jun 2019
      Part 3 - Home Shop Machinist, Jul/Aug 2019
      Part 4 - Home Shop Machinist, Sep/Oct 2019

      I did not read all of them, but from what I did read and what I saw of the others, they are top notch and well worth the cost of the back issues or of reprints. This discussion will probably prompt me to go back and read them in full.

      I guess a plug for our board's sponsor would be OK:

      https://secure.villagepress.com/stor...list/group/294

      All four issues seem to still be available.



      Originally posted by PS4steam View Post
      That is one cool tool, anyone recall the issue it was in the magazine?
      Last edited by Paul Alciatore; 03-31-2020, 06:42 PM.
      Paul A.
      SE Texas

      And if you look REAL close at an analog signal,
      You will find that it has discrete steps.

      Comment


      • #18
        Originally posted by Mcgyver View Post

        I'll take that as a complement

        A few things I tried to do with mine: 1) it uses a Starrett 199 master precision level and 2) it uses split cotters for the clamps 3) really versatile, with the adjustable feet (with brass pads - that avoids scoring your freshly scrape ways) its one size fits all; it works with any size or pretty much any geometry of way (the orginal kingway came in different sizes). A bit more work to make the split cotters, but its like riding in a Rolls, very luxurious . All the torque goes into clamping not bending the clamp material. Sturdiness is important, the clamps help with that as does using 5/8" bar. As for the 199, my logic was I had one and that one would find its way into most serious proponents bit of kit, saving the expense of precision vials. Without one, you could easily use precision vials instead....but the 199 is maybe the most accurate. That view comes from both the graduations (.0005/12") but also the distance in between graduations - easier sub graduation interpolation. The level rests in an adjustable 3 point arrangement. I've used it quite a bit and can highly recommend it (hows that for bias? )

        Here's a few shots. It mostly gives the function of the Kingway tool with a few improvements like the split cotters, but the last photo is of my own innovation, a sweep tool. Basically a angular contact bearing spindle for sweeping with an indicator - useful for scraping in a tailstock or headstock.












        See, thats the black magic i was expecting from a machine rebuilding tool! 😄

        Seriously, thats an impressive bit of kit, if a touch intimidating to look at for an inexperienced eye.

        Comment


        • #19
          I like his device, but in all honesty, the original King-Way is quite simple. Here is a pic of one in the box (not mine), followed by one in use.

          McGyver's is nice, but truthfully, you don't have to do that to get the results.His is especially nice if you are going to do a lot of scraping on different things, and want the bells and whistles and, of course, if you want to use an existing level.

          You do not actually need a level for 90% or more of what you will want to do. He went for the full Monty, and you can see the level provisions on the original, which I may put on mine someday. That day has not come yet.





          Last edited by J Tiers; 03-31-2020, 08:54 PM.
          CNC machines only go through the motions.

          Ideas expressed may be mine, or from anyone else in the universe.
          Not responsible for clerical errors. Or those made by lay people either.
          Number formats and units may be chosen at random depending on what day it is.
          I reserve the right to use a number system with any integer base without prior notice.
          Generalizations are understood to be "often" true, but not true in every case.

          Comment


          • #20
            Email of info sent.
            CNC machines only go through the motions.

            Ideas expressed may be mine, or from anyone else in the universe.
            Not responsible for clerical errors. Or those made by lay people either.
            Number formats and units may be chosen at random depending on what day it is.
            I reserve the right to use a number system with any integer base without prior notice.
            Generalizations are understood to be "often" true, but not true in every case.

            Comment


            • #21
              Paul

              Thank You for the list of issues

              Bob

              Comment


              • #22
                Originally posted by J Tiers View Post
                Email of info sent.
                And received! Thank you again for sending those over, thosell come in handy. Really, thanks for all the information, its helped narrow down a plan of action.

                At this point, i think im going to go for the "cheaters" rebuild, if the price comes out right. Im going to call around, see if i can find any place local who can grind in the saddle, then use the freshly ground saddle as the master to scrape the ways on the table and the base in. I figure that having someone competent grind the surface will result in a surface as good as my amateur self could scrape, and give a level of accuracy that is acceptable for the machine, and scraping in the matching surfaces will save some cost vs grinding the entire machine, as well as avoid the problems of running a ground surface against a ground surface. Again, its a 20+ year old import, i think cutting a few corners will hardly be the worst thing for it, though if ive missed anything im always happy to learn

                Comment


                • #23
                  epicfail48,

                  I am in a very similar situation as you. A couple of years ago I I bought an old (1950s era) 6 x 12 surface grinder. After bringing it home I discovered it is heavily worn. Somehow I was under impression the wear is around .015", but today I have checked the table and carriage ways and could not find more than .002" of wear. The original scraping marks are almost entirely gone and you can see and feel a ridge on the carriage way where it was mated with the table. Amazingly the ways are still quite straight, I could not put a .0015" shim between the ways and my non-certified straight edge.

                  Probably next year I will have more time and I I am thinking about restoring this grinder. Most likely the scraping would be required. I have no experience in it, but I am more than willing to learn. A few pictures of the ways are attached, they are not the best, sorry about that.
                  The table has one flat and one V-way, which are 18" long.
                  The top of the carriage has matching ways, but flat one is 20" long and V-way is 16.5" long.
                  The bottom of the carriage has two flat ways 16" long each.

                  I have a vertical mill big enough to fit the grinder parts, but it may not be necassary. What kind of measuring tools do I need to scrape the grinder? I have a 18 x 24 surface plate, but that's about it. A good straight edge is definitely needed, but what about the V-ways - how do I print and measure them?
                  Click image for larger version

Name:	IMG_2583.JPG
Views:	212
Size:	2.20 MB
ID:	1865733Click image for larger version

Name:	IMG_2584.JPG
Views:	206
Size:	2.13 MB
ID:	1865734Click image for larger version

Name:	IMG_2582.JPG
Views:	206
Size:	2.24 MB
ID:	1865735

                  Comment


                  • #24
                    Originally posted by epicfail48 View Post


                    At this point, i think im going to go for the "cheaters" rebuild, if the price comes out right. Im going to call around, see if i can find any place local who can grind in the saddle, then use the freshly ground saddle as the master to scrape the ways on the table and the base in. I figure that having someone competent grind the surface will result in a surface as good as my amateur self could scrape, and give a level of accuracy that is acceptable for the machine, and scraping in the matching surfaces will save some cost vs grinding the entire machine, as well as avoid the problems of running a ground surface against a ground surface. Again, its a 20+ year old import, i think cutting a few corners will hardly be the worst thing for it, though if ive missed anything im always happy to learn
                    you really want do the long piece first then scrape the shorter into it. It would be really awkward in the reverse....so if you were to have one ground, get the table ground. btw, in my scraping a few years ago I covered doing a T&CG which is fairly similar to a surface grinder
                    in Toronto Ontario - where are you?

                    Comment


                    • #25
                      Originally posted by Mcgyver View Post

                      you really want do the long piece first then scrape the shorter into it. It would be really awkward in the reverse....so if you were to have one ground, get the table ground. btw, in my scraping a few years ago I covered doing a T&CG which is fairly similar to a surface grinder
                      Funnily enough the ways on the saddle are actually longer than the ways on the table, by about 6 inches. Threw me for a loop too, finding that!

                      Comment


                      • #26
                        Originally posted by epicfail48 View Post

                        Funnily enough the ways on the saddle are actually longer than the ways on the table, by about 6 inches. Threw me for a loop too, finding that!
                        Maybe THAT'S how the ways got so torn up! Actually that's fairly normal, the table does not want to have issues of bending from cantilevered weight, etc.

                        Isn't there a cover over the ends of the table that should cover the ways? Most do have them.
                        CNC machines only go through the motions.

                        Ideas expressed may be mine, or from anyone else in the universe.
                        Not responsible for clerical errors. Or those made by lay people either.
                        Number formats and units may be chosen at random depending on what day it is.
                        I reserve the right to use a number system with any integer base without prior notice.
                        Generalizations are understood to be "often" true, but not true in every case.

                        Comment


                        • #27
                          Originally posted by J Tiers View Post

                          Maybe THAT'S how the ways got so torn up! Actually that's fairly normal, the table does not want to have issues of bending from cantilevered weight, etc.

                          Isn't there a cover over the ends of the table that should cover the ways? Most do have them.
                          Theres a metal shield that extends about 6 inches beyond the edge of the table, but i wouldnt call it a way cover. No wipers or anything either, not a whole lot of protection on the ways. Honestly, the only thing that surprises me about the damage is how little their is, or rather the fact that the machine gives halfway decent results still

                          Comment


                          • #28
                            Originally posted by mikey553 View Post
                            . A good straight edge is definitely needed, but what about the V-ways - how do I print and measure them?
                            Here'a one way, a level on the alignment tool is far easier and likely more accurate. (I do not get the claims you don't the level for this tool, its fundamental to its use: scraping ways into alignment). This photo was before I made the alignment tool. The V block was scraped and is a perfect fit to the V way, and also perfectly square to the V - done as a matched pair for use in photo 2 on the double V way. The complete reconditioning of this grinder was part of the series article on scraping. None of its rocket science, but you do have to puzzle through a sequence and plan to get everything square and aligned, base, saddle table (and pivoting table on this as its a T&CG)








                            Last edited by Mcgyver; 04-03-2020, 09:43 AM.
                            in Toronto Ontario - where are you?

                            Comment


                            • #29
                              Originally posted by Mcgyver View Post

                              (I do not get the claims you don't the level for this tool, its fundamental to its use: scraping ways into alignment). ......
                              So, why do you think it is so fundamental and absolutely required, so much so that you seem to claim the King-Way is worthless without it?

                              Easy to explain why the tool is very useful without the level.... the tool with an indicator is used (as shown all through the Connoley book) for measuring relationships, which is very fundamental to scraping for alignment. For instance to measure one "way" vs others. Or to measure the alignment of a mill saddle crosslide way to the column ways, etc. It then gives an "absolute" measurement, potentially to the "tenth".

                              The level is indeed "useful", but by itself, only gives a measurement of "local relative slope". That can be very useful, BUT you need to essentially do "mental calculus" to "integrate" the slopes into an actual measurement. You can argue that the level gives the slope and you are good when it shows no movement. And there is validity to that.

                              But, the typical level is calibrated to 5 tenths per foot. You must estimate between, which is easy enough to do. But it is far more easy to measure, for instance, a third "way" vs two others, using an indicator which may be direct-reading to tenths, exactly according to Connoley's diagrams, than it would be to try to do that with the level.

                              I would rather directly measure a parallel relation with an indicator and King-Way than try to prove it with a level, although in principle you CAN do that.

                              Each has their purpose, and the level seems to be useful for 25%, the indicator for 75%, of the needed measurements. That may even be over-estimated in favor of the level.

                              When you need a level, you need it. But the King-Way without the level is FAR more useful than the level without the King-Way.
                              Last edited by J Tiers; 04-03-2020, 12:05 PM.
                              CNC machines only go through the motions.

                              Ideas expressed may be mine, or from anyone else in the universe.
                              Not responsible for clerical errors. Or those made by lay people either.
                              Number formats and units may be chosen at random depending on what day it is.
                              I reserve the right to use a number system with any integer base without prior notice.
                              Generalizations are understood to be "often" true, but not true in every case.

                              Comment


                              • #30
                                Originally posted by J Tiers View Post

                                So, why do you think it is so fundamental and absolutely required, so much so that you seem to claim the King-Way is worthless without it?
                                .
                                Why would you say that? How you could you get to me seeming to claiming the Kingway design is worthless? I said the opposite, that my design is based on the functionality of the Kingway. The Kingway design does have a level as you know. My thought was around your statement "You do not actually need a level for 90% or more of what you will want to do." which is not true and undermines the main point of the device, mine or the Kingway.

                                Have you scraped any lathe beds or long sets of ways? Its maybe the most useful functions of the Kingway which mine provides using an external level. Being able to move a level along is its trick. From someone who's done it (using the level to keep say a longish V and flat parallel), that really is the tool's value.
                                Last edited by Mcgyver; 04-03-2020, 01:28 PM.
                                in Toronto Ontario - where are you?

                                Comment

                                Working...
                                X