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  • buying first mill

    Hi, I've been lurking (and searching) here for quite a while. My home gunsmithing has reached the point where a small milling machine is needed.

    Since my day job and the distance to the nearest votech school are incompatible, this is going to be a self-taught process. I've been reading Machine Shop Practice Volumes 1&2 to see what I'm in for.

    Constraints: Due to zoning, power, and floor strength issues, a 2000lb. machine is not possible. I mostly work on pistols, but will be doing some rifle receiver work in the future. So big capacity would be nice, but small precise work is the majority of what it must do.

    Based on searches here, it looks like a Prazi F1210 with ball screws will be a machine that will do what I need for the foreseeable future, and easily converted to CNC. I prefer high quality tools, and have been saving up for this purchase.

    I'm willing to pay the price, but is there some other solution I should be considering? I'd rather not recondition an old machine if I don't have to. Is the MT2 spindle a major drawback? I think I read somewhere that R8 is a USA-only spindle.

    Also, I'm starting with only some mics and verniers. Any advice on a shopping list for books, vices, collets, mill bits, dial indicators, measuring tables, etc. would be greatly appreciated. I have a 'connection' into McMaster-Carr, and have ordered from MSC, so I'm aware of those two sources.

    Thanks in advance for your help!

  • #2
    Don't worry about Morse #2. You can get everything you need from MSC, Travers, or whoever. "Everything" will be maybe 4 collets, a drill chuck with a 1/2" straight shank to hold in your 1/2" collet, and maybe a 2" dia. boring head with a Morse #2 shank. (Do NOT get the boring head with a straight shank.) You can get Morse #2 end mill holders, if you want, but I'd just use collets.

    Morse #2 limits you to 1/2" dia shanks or less, but for the work you contemplate doing I expect that will be quite adequate.

    ----------
    Try to make a living, not a killing. -- Utah Phillips
    Don't believe everything you know. -- Bumper sticker
    Everybody is ignorant, only on different subjects. -- Will Rogers
    There are lots of people who mistake their imagination for their memory. - Josh Billings
    Law of Logical Argument - Anything is possible if you don't know what you are talking about.
    Don't own anything you have to feed or paint. - Hood River Blackie

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    • #3
      I would avoid if possible getting a milling machine with MT taper in the spindle. R8 is the way to go, as it give you the most flexibility and low tooling cost. It's also a lot beefier. Peruse through those catalogs and you'll see what's available in terms of attachements for MT and R8 taper.

      Having said that, Prazi F1200 series are very nice machines, albeit a little pricey. Ro Fung, I believe also makes a bench top milling machine with dovetail column, which you should consider.

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      • #4
        I have the Prazi BF400 mill, which also uses 2MT, so my experience is fairly relevant.

        A vice is a must. I found my generic 4" width vice to be adequate; a bigger one is often useful, but they start getting pretty heavy.

        Get a center finder that you can chuck in your mill holder or Jacobs chuck; you'll use that to dial in you vice to make sure its jaws are parallel to the table.

        I use parallels a lot, to lift work above the base of the vice.

        I also use the rotary table a lot; I have a 4", but again a bit bigger would be nice. Make sure it is the type that works vertically too.

        A boring head is very useful. I saved some mony by assembling mine from a head and a 2 MT shank that fits the head.

        A flycutter is also good to have.

        Regards,

        JE

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        • #5
          So a 2K lb machine is too big, how about 1100 lbs. Penntool sells this:
          http://www.penntoolco.com/catalog/pr...ategoryID=2441
          which would handle a wider range of projects and the mass does help.

          If that is still too big, a RF-45 type mill/drill might be an alternative. Enco, Grizzly and Penn sell them in several variations.

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          • #6
            Thanks for the input. So the only concern about the MT2 taper is the maximum shank size of 1/2"? Collets make sense to me, the set-screw end mill holders seem like they'd be more prone to mounting problems (burrs, etc). I'll add parallels to my list, too. "Center finder": is this the same as a Starett edge finder, using the cone tip?

            rotate: Did you mean Rong Fu 45? I found a similar machine here:
            http://www.lathemaster.com/HEAVYDUTY...E%207045FG.htm
            Definitely less money, but how is the quality of the Taiwan machines?

            sidneyt: penntool's site appears to be down. Do you know the machine name so I search for it?

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            • #7
              zzxx99,

              I'm not sure what the model number is, but make sure that the unit is made in Taiwan and not mainland China. Many Tawainese companies actually have manufacturing done in China so be sure to ask. As for the quality, some Taiwanese products can be pretty good. There's a local dealer that sells Bridgeport style milling machine by a Taiwanese company called First, and they are very well built. Good luck.

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              • #8
                I should have said "wiggler" rather than "center finder". The wiggler has a thin rod with a point on one end; the other end is a ball that is clamped into a shaft that is held by your chuck. You chuck the wiggler, get the point approximately in line with your mill's spindle axis, turn on the mill, and use your thumbnail to gently push against the wiggler tip until it is running true. Turn off the mill and use the quill to lower the point into the center punch mark on the work you are trying to center; press lightly, and turn the spindle a rev or two by hand. Quill up and mill on; if the wiggler tip is not true, true it up again, adjust the table position, and try again. Repeat until tip runs true. Much faster to do than describe, once you've done it a few times.

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                • #9
                  Jeastwood,

                  Did you outfit your BF-400 with Prazi's accessories (fly cutter, chuck, vise, end-mill holder) or did you go with other brands? The Prazi accessories seem expensive and no one knows much about them or even has them listed in any sort of detail. Thanks.

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                  • #10
                    Are you making race guns or keeping the locals guns working?
                    It will take different equipment to make them, then to fix them.
                    If you think that you want to try to do it all, bigger is better.

                    Good luck
                    Happy holidays
                    Be safe

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                    • #11
                      I have a Clausing vertical mill, which weighs about 750 lbs. Much harder to move and find space for than a Prazi, but much easier than a Bridgeport. The Clausing and the generally similar Rockwell are only available used (and then only if you can find one near enough), and I think you are looking for a new machine which wouldn't need any restoration & would be easier to convert to CNC, therefore I won't try to "sell" you on my favorite machines.

                      I haven't found the MT-2 spindle to be a problem. Yes, there's more stuff available (new and used) in R-8, but with a small mill I don't think you'd really want to use anything larger than 1/2" shank, and most useable-sized tooling is readily available in 1/2" and/or MT-2.

                      The feature I find *very* useful, which isn't available on smaller mills or mill-drills is the knee. Aside from usually having more Z-axis travel to start with, it allows you to change head to table distance by a lot without disturbing alignment, or to dial in a few thousandths more accurately than by using the quill. (The latter problem can, like most, be solved by throwing more money at the machine, i.e. digital readout.)

                      I also have Machine Shop Practice Volumes 1&2 and think they are excellent books. I've been working metal for decades, but only machining for a couple of years, and my favorite beginner book is Tabletop Machining, by Joe Martin, the Sherline guy. It has a lot of info specific to Sherline machines and is very much model engineering oriented, but is *very* clearly written and tells you _why_ you should do something, as well as how. It also has advice on what you actually need, etc. Check out their website for some useful info and a good sampling of the writing and illustration styles of the book. BTW, I don't own anything from Sherline except the book.

                      On tool suppliers, note that ENCO and MSC are owned by the same company, and the product lines overlap some, with the same item often costing a bit less from ENCO. They have a big operation there in Atlanta, too.

                      If you're up for a long drive next month, consider attending Cabin Fever Expo in York, Pa. The Prazi importer usually has a booth there, so you can get your hands on those and other machines and see a lot of inspirational metalwork, plus rub shoulders with lots of folks with similar addictions, including some regular posters here.

                      Hope you're able to satisfy your mill lust soon, I know what it's like. 8)

                      BillB

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                      • #12
                        Littleroy,

                        I bought no accessories from Prazi. I alread had lots of tooling to fit my MT1 tapered Sherline lathe, so at least at first I adapted these to the MT2 Prazi using easily available (MSC, etec.) MT adapter sleeves. There is indeed LOTS of MT2
                        tooling available from MSC, Travers, Enco,
                        et. al.

                        T nuts for the table are pretty easy to make yourself, but are cheap to buy also.

                        Regards,

                        Jeff E.

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