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  • #16
    Same song second verse

    It would probably take EDM to enlarge the clearance holes. There are 15 holes. Would anyone care to hazard a guess at the cost. If one had several done at the same time would that be any cheaper per unit?

    Sir John Please do report on the effects of commercial Annealing. Surprisingly, I just discovered that there is a commercial heat treating business out here in the boonies near me. I need to get over there and meet them.

    Harvey, Thank you for the Travers information.

    Robert, How do you find and identify the ones that are done properly?

    James, On first look I was not sure that they fit together that well. Thank you for your input.

    Yesterday, I was doing a setup that would have been facilitated by being able to attach the 123 blocks together. It would have also been easier if I had more than one pair. The $53/pair for Travers kind of makes me flinch, but having the right tool for the problem at hand helps one to forget the original cost.

    I am past owning my own EDM but I was curious as to what a commercial shop would charge for something like opening up the through holes.
    Byron Boucher
    Burnet, TX

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    • #17
      Please forgive me — I don't mean to be impertinent, I'm simply a complete newbie — and after reading this discussion, I have some questions:

      1. Why must machinists BUY 1-2-3 blocks, especially if the design is wanting? Why can't they or don't they make their own?

      2. For common machining setups, how important is it that the blocks be square and parallel to .0002"? Would .0005" suffice? Would .0001" be much better?

      3. Why do the blocks need to be hardened? I would think that un-hardened blocks would be more desirable, since they would be both repairable and modifiable.

      To put it another way, is it unrealistic for someone with a mill (but no surface grinder) to think they can make their own, sufficiently accurate, 1-2-3 blocks?

      What about making 1-2-3 blocks with Durabar and then hand-scraping them? Or simply using 4140PH and a good fly cutter or face mill?

      Thanks.

      -Chris

      Comment


      • #18
        Originally posted by Boucher View Post
        Robert, How do you find and identify the ones that are done properly?
        I wasn't exaggerating -- all non-Chinese 1-2-3 blocks I've ever seen can be connected together.
        I have a nice set of Moore & Wright blocks I got off Ebay for ~ $40, and that wasn't a spectacular/rare deal by any stretch.
        "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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        • #19
          Originally posted by John Stevenson View Post
          DP,
          Whilst I fully agree with what you say, I question why a retailer has to reject them given there is no 'standard' on how these things should be used or what they were used for.

          Now if they were advertised as being able to bolt up in certain configurations then fine but the use of these things is very obscure.
          Given there is probably 1 million sets out there why is there not 1 million unsatisfied customers ?
          Probably because they all use them in different ways.

          As regards the proper old design it's a chance you have to take, the old Starrett blocks were fine, current new one being sourced from China or India are wrong. I have a set of each.
          I think it is clear there is interest in interconnecting the blocks using the intended original method - direct fastening. When I bought my set I presumed they could be bolted together, or that bolts could be found that would at least fit the threaded holes. Neither is possible with the set I bought when makes me wonder why they went to the trouble of drilling and taping any holes at all.

          Ultimately there is an implied purpose of the holes but which cannot be realized because of incorrect manufacture and you have said as much here. That is fraud's next door neighbor, misrepresentation. I've since used my blocks as very large parallels as I've purchased an angle plate for operations that can advantage themselves of it. My retailer did not volunteer these holes were useless for the intended purpose and so is complicit in my receiving gear I did not want or need.
          Last edited by dp; 10-22-2012, 01:13 PM.

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          • #20
            Originally posted by oldtiffie View Post
            Dennis,

            if it bothered me that much - or at all - which it doesn't I'd make a set of aluminium ones - but I can't see the need.
            I misunderstood the scope of your original statement, Tiffie - you didn't indicate your opinion was not for the general case (the average machinist for whom these are targeted, and in fact the point of the OP) but for your own uses and that's fine. I also make personal exceptions to the general rule (thread testing needles, for example ).

            Comment


            • #21
              Originally posted by Boucher View Post
              I am past owning my own EDM but I was curious as to what a commercial shop would charge for something like opening up the through holes.
              I can't help you with a specific number, but I know for sure it would cost more to EDM out the holes than to simply purchase new blocks with the proper holes. EDM is a very slow way to remove metal and then you have the need to purchase and perhaps machine the graphite electrodes. Even if you supplied the electrodes ready to mount in the shop's mounting system, I would guess the shop would still have close to two hours into drilling the flushing holes in the electrodes, setting things up in the machine, and machining the holes. Around here, that's going to push you past $100 by a fair amount.

              Edited to add: Talking about plunge EDM here. The holes could be done on a wire EDM as well, but it wouldn't be any cheaper. The wire used is expensive and the time to thread and cut the multiple holes would take at least as long as on a plunge machine.
              Last edited by George Bulliss; 10-22-2012, 01:58 PM.
              George
              Traverse City, MI

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              • #22
                cegreen:

                I am far from expert (noob w some experience?) but I think the crux to all of your questions is how much accuracy do you need? I could whittle out something but unless what I want to use them for can be made and be out of size/tolerance by 1/4", they wouldn't do me much good.

                Can they be made? Certainly and I would hazard a guess that there are more than a handful who are "here" (bbs) that have made their own. Judging from readings, they were often a project for machinist w down time or an apprentice. Same for "V" blocks.

                Again, I am not certain but think the reason for grinding being the "norm" are the tolerances that can be held.

                Could they be hand scraped? No reason why not that I can think of but at some point you need to measure flat and square. I mention that last bit because it goes back to tolerances. If you have to have something made that needs to be .00001 flat over a given distance or square relative to something of a given size (distance?) you need something that can measure at least that fine.

                Edit: some of the other questions come down to time is money, blocks I have are import but still finer tolerance than I am likely to accomplish unless I am very, very lucky. I could see where hardened would have its value (not sure about repair and or modify coming into the picture). .0005", for argument sake is import maybe $ 20, .000001" is Suburban or Moore quality, in a matched set, who knows but its a lot more.
                Last edited by RussZHC; 10-22-2012, 02:44 PM. Reason: Add another thought

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                • #23
                  Right mine went over to the hardening shop today, got the splined shaft back this afternoon [ rush job ] but the blocks will stay in over night.
                  I'll then try with a Cobalt drill tomorrow.

                  Whatever happens because they have been heated and won't look pretty for a start I'll lick them up as pairs on the surface grinder.
                  I am not bothered that they are 1" x 2" x 3" to 0.0001 tolerance in fact I much prefer my packings and parallels to be undersize so the blocks don't get trapped before the work.

                  In reply to Chris I much prefer my packings and parallels to be tough as opposed to hard, this way if you make a mistake it doesn't cost you a cutter and you can always lick a few dings up.
                  .

                  Sir John , Earl of Bligeport & Sudspumpwater. MBE [ Motor Bike Engineer ] Nottingham England.



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                  • #24
                    Originally posted by RussZHC View Post
                    Edit: some of the other questions come down to time is money, blocks I have are import but still finer tolerance than I am likely to accomplish unless I am very, very lucky.
                    You might have also noticed that the "corrected" Chinese 1-2-3 blocks are now showing up at MSC and Enco. I know SPI has them, don't remember the price, but it was cheap.
                    "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

                    Comment


                    • #25
                      Originally posted by lazlo View Post
                      I wasn't exaggerating -- all non-Chinese 1-2-3 blocks I've ever seen can be connected together.
                      I have a nice set of Moore & Wright blocks I got off Ebay for ~ $40, and that wasn't a spectacular/rare deal by any stretch.
                      How would you attach a set of one hole 1-2-3 blocks to each other? Or have you just not seen them?

                      Comment


                      • #26
                        Make and use a set/numner of "captive/waisted" bolts - see my previous post (#4) for details.

                        If your block that you want the screw through is say 2" thick, and all the blocks are tapped the same (say 3/8-unc) the bolt/screw needs to be a good quality (say high-tension) with its length needs to be say block width + 3 screw diameters minimum. Turn a plain section on the bolt shank that is at least block tickness + 1 bolt diameter (from the bolt head) from the head - screw shankplain section to be bolt/screw minor diameter (maximum).

                        Now screw captive bolt into the 2" long 3/8-unc tapped hole in the 2" block. The screw will be loose/free in the tapped hole with a 3/8-unc end section protruding from the 2" block. The protruding 3/8-unc section of the bolt can be inserted/screwed into another block and tightened as required. Use washers as required.

                        The bolt/screw is "captive" in the 2" block as it can rotate fully and move length-wise partially but cannot come out unless deliberately screwed out.

                        It also means that a block can be fastened to anything that has a 3/8-uns tapped hole without the need of clamps or packing.

                        Its use is not limited to "blocks" either.

                        There are numerous variations on the principle limited only by need and imagination.

                        I/ve seen and used this since my "early days" and it had been around for a long time prior to that.
                        at:

                        http://bbs.homeshopmachinist.net/thr...375#post803375

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                        • #27
                          Originally Posted by oldtiffie

                          I think that the hole (whether tapped or not) is as much to do with ease of heat-treating and control of distortion and cracking due to internal stresses and with a reduction in processing time (and cost).

                          I can't see that the non-tapped holes are an issue at all.
                          Originally posted by dp View Post
                          They're too small to pass a threaded bolt or all-thread through unless you don't care if the bolt doesn't match the threaded holes. It means you can't bolt one block to another unless your bolt passes through both blocks and is nutted externally.

                          All the holes were drilled to the same size and some were threaded. The holes that are threaded are a tight fit, sometimes too tight, but the unthreaded holes needed to be drilled larger than the major diameter of the bolts to allow the bolts to pass through. That wasn't done. That this error has been going on for years and that no retailer has rejected the parts says much about QA in machinist tools.
                          I can't see that there is an issue at all here. It seems to me a lot of kerfuffle about a lot of nothing at all.

                          The blocks I have (up to 6") are all similar and quite functional - and the non-tapped holes have never been a problem and I can't see them being one.

                          In most cases I use tools etc. "as is/supplied" as I rarely have a real need to "tweek" them.

                          I doubt that Starrett's blocks (all holes tapped) were - or are - a formal USA standard of any kind. Starret are/were not the only USA company to make them. My guess is that Starrett saw them else where and copied them (no paternt on them?), tapped all the holes and "ran with it". Perhaps the other USA companies that made them copied Starrett - who knows and who cares anyway? Certainly not me.

                          The "some drilled holes not tapped" model is just as much a "standard" (or not) as the Starrett model is and perhaps just a variation on a theme.

                          Given that in a lot of cases a "block" is used as a packing clamp or spacer etc., I cant see that much accuarcy at all is needed and if it is surface grinding is a quick and eacy accurate solution. The normal "Chinese" blocks are quite sufficiently accurate for parallel and squareness for just about any purpose and as such are quite good enough (for me anyway) "as is" "right out of the box".

                          Given that the "some holes are not tapped" variation is pretty well the default it seems that a "Starrett" is a "special" and if asked for ordered will be a costly "special".

                          If using the blocks for the required purpose is not practical - use another of the many other methods and options avaiable in the average shop.

                          Comment


                          • #28
                            Originally posted by Harvey Melvin Richards View Post
                            How would you attach a set of one hole 1-2-3 blocks to each other? Or have you just not seen them?
                            WTF? Yes, most Western metrology companies make/made single-hole 1-2-3 blocks, including Starrett. Obviously we are talking about the 1-2-3 blocks with 11 or 23 holes, where the through holes are supposed to be 5/16".

                            The Chinese botched the prints and drilled all the holes with an F-drill, so you can't use 5/16" bolts to make angle blocks with them.
                            Last edited by lazlo; 10-22-2012, 05:30 PM.
                            "Twenty years from now you will be more disappointed by the things that you didn't do than by the ones you did."

                            Comment


                            • #29
                              Originally posted by oldtiffie View Post
                              I doubt that Starrett's blocks (all holes tapped) were - or are - a formal USA standard of any kind. The "some drilled holes not tapped" model is just as much a "standard" (or not) as the Starrett model is and perhaps just a variation on a theme.
                              Starrett 1-2-3 blocks do not and never did have any tapped holes. They have five through holes that don't match each other in such a way as to make any convenient fixture.

                              For my purposes, I have never had occasion to bolt my 1-2-3 blocks together, and see no reason to do same.
                              Jim H.

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                              • #30
                                Originally posted by oldtiffie View Post
                                Given that in a lot of cases a "block" is used as a packing clamp or spacer etc., I cant see that much accuarcy at all is needed and if it is surface grinding is a quick and eacy accurate solution. The normal "Chinese" blocks are quite sufficiently accurate for parallel and squareness for just about any purpose and as such are quite good enough (for me anyway) "as is" "right out of the box".
                                I really can't let this go without comment.

                                123 blocks that are not ground very accurately square and to size within tenths are simply not 123 blocks in my view. The whole point is their their accuracy. Original 123 blocks did screw together easily and that is also part of their DNA. The fact that Chinese 123 blocks don't, just means that they are faulty. The fact that you can still use them to some extent even with this fault is fortunate.
                                Bill

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