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Buying a CNC Lathe & CNC Mill - Need Advice

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  • #16
    You have $10,000 to spend and it seems very limited experience....(that wasn't judgemental)

    Many homebrew CNCs are ok at best, and often cost a significant amount of money.

    If I was in your shoes I would buy a Tormach 440 and a manual lathe. Between the 2 you can accomplish a significant amount of work. You can add on a CNC lathe down the road. For many parts a CNC mill is a necessity in my opinion, but not so much a CNC lathe. You can also get creative and use your mill as a lathe for parts that you can't manually machine.

    Lots of people don't like Tormach, but if you stick to the base machine (and maybe a stand) they are very reasonably priced for what you get. You also get Tormach's very good support.

    I have 2 Tormachs in the shop. They aren't the equivalent of a Haas machine by any stretch, but they are a fairly well engineered package that if you tried to do it yourself would probably cost more, and take a year of your shop life.
    Last edited by enginuity; 06-10-2020, 10:40 AM.
    www.thecogwheel.net

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    • #17
      Without machining experience at all you are entering a totally different world.
      Brass and aluminum are different animals to cut. You would most likely need to adjust tooling and expenses. Brass will cost you a fortune by the way
      You are going into this blind. Some of your experience in printing plastics will carry over but it is a different world.
      If you went the conversion route there is quite a bit of 'tinkering' around to get it going correctly.
      An automatic tool changer right now is probably out of your budget with a machine.
      At minimum you would probably need one of the mill/drill type machines which would provide you the envelope and clamping area you would need.
      I would also see about buying small manual machines so you know what you are getting into first

      You have not even addressed the CAD/CAM side of this equation. The cost of a software package will set you back some money.
      CAD drafting is one skill I hope you have.
      Please do not tell me you are just going to scan in a part and produce it. It is not that easy without editing and and $$$ for a software package to do that.

      I have a Sherline CNC mill and I am quite sure the parts you would try to cut would be too big for it.
      I also have access to a Hurco VM1 15hp machine and I think that is out of your budget.
      I have cut small plastic injection molds in aluminum on the Sherline CNC machine without issues. Need to reset the tool Z level each change of tool
      It is capable of doing very good work within its limits.
      Others have mentioned tooling costs and they are correct on the expenses. It is not cheap.
      End mills only last so long they dull and they also break. Inefficient code, bad connection to the computer etc

      I applaud you watching videos about the process so you are educated about what you want to do and continue to do that.
      If you continue with this without knowing more about what you need you will be getting pennies on your dollar investment when someone buys it from you.

      Comment


      • #18
        He said he is good with 3D CAD, so he is half way there. I believe if you are a one man shop, CNC is a second step after having manual machining experience.

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        • #19
          Totally doable.

          My cnc lathe is an Emco120, very capable small lathe. Paid 5k used.
          My cnc mill is a bridgeport boss5. Paid 5k used.

          Tooling? Also doable because of the commonality of the size and type. JR

          P.S. Whatcha got to barter with. Id barter both away. JR

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          • #20
            Originally posted by mc_n_g View Post


            You have not even addressed the CAD/CAM side of this equation. The cost of a software package will set you back some money.
            CAD drafting is one skill I hope you have.

            If one buys a 2 axis lathe with a conversational control you would not need CAD/CAM nor knowledge of G Code, you do however need fundamental machining knowledge.

            The controls that come to mind are beyond the OP's budget such as Hass Visual and Mazatrol, old Bridgeport EX Paths and EZ Traks are extremely easy to fingercam at the machine even for complicated parts.

            This is a threading cycle on a 1996 BP EZ Path in MDI, 1 1/4-4 acme X 10 3/8" long. No G Code required. The Rapid move and the program stop are not required I simply added them because I like run the tool close to the start and have it stop so that I can see that everything is in correct position, this can avoid crashes.

            Type the thread data into the fields and let it eat


            I programmed this part at the machine in 30-45 minutes from a paper drawing, no CAM, no G code. Worked well for 300 parts. It is running at 1/2 speed because I turned the coolant off to take the video.
            Last edited by Bented; 06-10-2020, 05:02 PM.

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            • #21
              So R8 spindle collets are simply the original Bridgeport manual mill setup, not really for CNC. They are popular at the hobby level because there is so much R8 tooling available at low prices. R8 is repeatable only when using R8 arbors to hold a tool, not a collet.

              Tormach TTS is a low cost tool holding system based on a 3/4" arbor that when used with an R8 spindle becomes repeatable by pulling up against the spindle nose. It works well for low horsepower machines but doesn't hold well for higher power machines or even a Bridgeport using the back gears for torque. This is because when the toolholder comes up against the spindle nose the friction essentially doubles on the collet as it must now slide against the toolholder and spindle. I have TTS tooling on my minimill size CNC where it works great. Because the spindle is R8 I get to use an R8 Boring bar, R8 collets, R8 3 jaw lathe chuck etc.

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              • #22
                Originally posted by RB211 View Post
                Nothing complex, even a simple part can use three different tools. Want to drill holes? That can be between 1 to 3 tools depending what you want. Spot drill, drill, chamfer. Threaded? Well... Make that four if you include a thread mill. You starting to see the dilemma with not having a tool library and having to reset the Z between tool changes?
                R8 isn't the best but a BT30 spindle is too big for a Taig, like putting a V12 engine on a golf cart.

                Hello,

                I get your point about the convenience of rapid tool changing.


                Apparently GlockCNC makes R8 headstocks that can be used with TTS on a Taig mill.

                So after researching, I've drawn up this package below. Tell me if you agree :


                1) Purchase a CNC Taig Mill with ball screws but MINUS their headstock and motor.


                2) Purchase an R8 headstock (and corresponding draw bar) from GLockCNC as mentioned here.
                I assume this would enable me to rapidly change R8 tools - with a cordless impact driver.
                Maybe its not as fast as the air pressure based system. But its good enough for me :

                https://glockcnc.com/r8-mill-headstock/


                3) Purchase a more powerful motor (about 3/4 hp ?) as mentioned by John's video below.
                Either that or the 750 Watt (1 hp) motor offered on GLockCNC's website :

                https://www.youtube.com/watch?v=Rjk8W6ZYc0Y


                Optional upgrade :

                There is a more sturdy frame upgrade for the Taig as described in John's video above.
                The stock Taig frame is reasonably sturdy based on what I've reading.
                So I'll skip that for now.



                While I understand the Tormach 440 might be better, would you say the package I've put together above is a good setup?

                Comment


                • #23
                  Originally posted by mc_n_g View Post
                  If you went the conversion route there is quite a bit of 'tinkering' around to get it going correctly.

                  You have not even addressed the CAD/CAM side of this equation. The cost of a software package will set you back some money.
                  CAD drafting is one skill I hope you have.
                  Please do not tell me you are just going to scan in a part and produce it. It is not that easy without editing and and $$$ for a software package to do that.

                  Thanks for the info and advice.

                  I have been looking at perhaps taking a couple of courses in (manual?) lathe and milling operations at a local college.
                  There are courses on reading and creating mechanical drawings, CNC courses.. etc. as well.

                  Essentially those would be evening / weekend classes I'd attend ...in addition to my day job.
                  I'm not sure what to take or whether the effort would be better spent trying to teach myself through experience.

                  Due to the Covid-19 situation however, classes (might) start in the Fall only.


                  I did take courses in Solidworks and have some proficiency in that.
                  Enough at least to do what I need to do in terms of making parts and assemblies.
                  I've 3D printed my assemblies and assembled them to make working prototypes which are fairly complex.

                  I notice however many metal machinists are using Fusion 360.
                  I'm willing to learn Fusion as well if that's what it takes.

                  I'm eager to get going on my journey to becoming a competent metal machinist and not get bogged down in decision making.
                  If that requires having to spend extra money to expedite the learning process, I'm willing to spend it.

                  I've found in life that skills I've worked to develop often end up being among the best investment decisions I've made.

                  Comment


                  • #24
                    Originally posted by enginuity View Post
                    If I was in your shoes I would buy a Tormach 440 and a manual lathe. Between the 2 you can accomplish a significant amount of work. You can add on a CNC lathe down the road. For many parts a CNC mill is a necessity in my opinion, but not so much a CNC lathe. You can also get creative and use your mill as a lathe for parts that you can't manually machine.

                    Lots of people don't like Tormach, but if you stick to the base machine (and maybe a stand) they are very reasonably priced for what you get. You also get Tormach's very good support.

                    I have 2 Tormachs in the shop. They aren't the equivalent of a Haas machine by any stretch, but they are a fairly well engineered package that if you tried to do it yourself would probably cost more, and take a year of your shop life.


                    That might be a good plan - Tormach 440 and a cheap manual lathe.
                    The mill is indeed more important than the lathe, you're right.
                    Many Youtube videos I've watched like Blondyhacks makes that point.

                    The price for a Tormach however is closer to $8000 for the "starter" package than the advertised $5000 base price.


                    I have a few questions:

                    Is the Tormach easy to fix if it breaks down?
                    Does it break down?
                    And how expensive will it be to fix if it breaks down.

                    What other additions would I need to make beyond repairing the hole in my wallet from the $8000 sticker shock.

                    Comment


                    • #25
                      Originally posted by RMinMN View Post
                      Somewhere along the line you need to learn CAM which seems to me to be nearly as complex as CAD and has to fit between CAD and CNC.

                      What would be the best way to learn CAM ?
                      I notice many use Autodesk Fusion 360 for CAD & CAM.
                      Should I be learning that now?

                      I'm proficient in Solidworks CAD.
                      Never tried using (or even seen) Solidworks CAM however.

                      What CAM software package are you using?


                      I'm gonna be dead before I get to mill my first aluminum part on my own machine with all these things to learn and do.

                      Comment


                      • #26
                        Originally posted by mechanica View Post


                        Hello,

                        I get your point about the convenience of rapid tool changing.


                        Apparently GlockCNC makes R8 headstocks that can be used with TTS on a Taig mill.

                        So after researching, I've drawn up this package below. Tell me if you agree :


                        1) Purchase a CNC Taig Mill with ball screws but MINUS their headstock and motor.


                        2) Purchase an R8 headstock (and corresponding draw bar) from GLockCNC as mentioned here.
                        I assume this would enable me to rapidly change R8 tools - with a cordless impact driver.
                        Maybe its not as fast as the air pressure based system. But its good enough for me :

                        https://glockcnc.com/r8-mill-headstock/


                        3) Purchase a more powerful motor (about 3/4 hp ?) as mentioned by John's video below.
                        Either that or the 750 Watt (1 hp) motor offered on GLockCNC's website :

                        https://www.youtube.com/watch?v=Rjk8W6ZYc0Y


                        Optional upgrade :

                        There is a more sturdy frame upgrade for the Taig as described in John's video above.
                        The stock Taig frame is reasonably sturdy based on what I've reading.
                        So I'll skip that for now.



                        While I understand the Tormach 440 might be better, would you say the package I've put together above is a good setup?
                        No, GlockCNC sells crap. The R8 spindle I purchased was custom made by a machinist who used bearings rated to 15,000 RPM and the spindle bore was finished ground in situation with the bearings. The price I paid also includes the pneumatic drawbar setup and Tormach R8 collet which is ground flat on the bottom. You can find the machinist on the Taig Facebook group.
                        The upgraded steel frame is also sold on that same group, but the kid that makes them doesn't know what a dial indicator is, and has zero quality control. I am going to machine mine square and fix his mistakes.

                        The Tormach 440, even at 8,000$ would be a huge improvement over what I have ended up with, for not much more money.

                        As for a motor for the Taig, the choice is yours. Some use a DMM servo motor, some use a Consew sewing motor. For now I am going to use the stock motor at a stuck spindle speed of 4500 rpm, using a 40/30 pulley setup using a GT sized pulley running 10mm / 3/8 belt. A standard 3 phase 1hp motor is just too big and heavy without going with a counterweight setup.

                        As you can see, I am still not done paying money to get my Taig working to my satisfaction, why I am suggesting to you that you just buy a Tormach. I wish someone told me what I am telling you.

                        Comment


                        • #27
                          Originally posted by mechanica View Post


                          I understand what you are saying.
                          If I had the luxury of time, believe me I'd do exactly that.
                          I'd buy a manual mill and spend months playing with it, then do a conversion on it to a CNC, ironing out all the bugs..etc.
                          I'm sure learn a ton along the way and have fun doing so.

                          Unfortunately I don't have the luxury of time.
                          I have to get caught up in a hurry and start making parts.
                          I'm going to have to learn this by doing.

                          I'm not completely clueless about CNC.
                          I have experience 3D printing complex parts in ABS and PLA plastics.
                          I don't have experience with CNC metal working however.

                          I have purchased a book for beginner machinists and I'm reading up as fast as I can.
                          I'm watching a ton of Youtube videos on the subject and googling away.

                          Maybe I am pushing ahead too fast, I don't know.
                          3d printing and CNC machining are only similar in that they both use g-code. Knowing how to run a 3d printer woont help you with a mill, because again, its not just the programming. Its the fixturing, knowing what tools to use when, knowing how to keep a part from being turned into shrapnel, preventing the tool from destroying itself, planning out the sequence of operations to make sure that one operation doesnt take away your ability to fixture a part for the next operation, knowing how different metals behave under the cut.

                          Seriously, if youre going into this expecting to hit the ground running and be making parts day 1, youre going to be losing money incredibly fast. Someone else already presented the best solution; if you need the parts not, subcontract out to a job shop to have them made while you do whatevers needed to learn the machines, BEFORE dropping $10k on something you dont know how to operate. Take a class, sign up for an apprenticeship, whatever.

                          Learning by doing sounds fantastic until you destroy a machine with a hard crash, or worse, injure yourself with it. Again, i strongly recommend that you reconsider going out and dropping that much money on new tools until you know the basics of how to use them. Mills and lathes arent like printers and plastic isnt metal. Theres a different skill set there, and a whole host of problems youre sweeping away because youve designed complex parts

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                          • #28
                            Originally posted by mechanica View Post



                            That might be a good plan - Tormach 440 and a cheap manual lathe.
                            The mill is indeed more important than the lathe, you're right.
                            Many Youtube videos I've watched like Blondyhacks makes that point.

                            The price for a Tormach however is closer to $8000 for the "starter" package than the advertised $5000 base price.


                            I have a few questions:

                            Is the Tormach easy to fix if it breaks down?
                            Does it break down?
                            And how expensive will it be to fix if it breaks down.

                            What other additions would I need to make beyond repairing the hole in my wallet from the $8000 sticker shock.
                            If you are really concerned about the $8000, just buy the base machine for $5000 and build / find a stand. If you go the Taig route you need to make up a stand anyway. When I purchased my 770M I opted for the Tormach stand - it was really well engineered and I couldn't make it for what they charge by the time you include paint etc.

                            The Tormach is very easy to fix if you have some mechanical / electronics aptitude. Tormachs are not industrial machines so you should be a prepared somewhat for the eventual failure. But the good news is Tormach offers full schematics, and you can order all the parts directly from Tormach for fairly reasonable prices. For example, if your spindle goes bad you can order a new cartridge. Other than a stepper driver burning out I've had no major failures on the Tormachs I have used over the years. (I have them in my shop, and I worked with them in the past).

                            One of Tormach's big benefits is Path Pilot. Yes it's Linux CNC under the hood, but they have added a number of very handy conversational programming functions that work well.

                            Again I'm not a Tormach fan boy. It is a niche machine. They are not industrial. But for a small home shop they are very good. Industrial machines are significantly better and can be had for soemtimes less money. But that can be a crap shoot. I bought Tormachs because I wanted to make parts ... not work on machines. Everyone is different.

                            If cash was limitless I would buy a Haas Mini Mill.


                            www.thecogwheel.net

                            Comment


                            • #29
                              Originally posted by RB211 View Post
                              No, GlockCNC sells crap. The R8 spindle I purchased was custom made by a machinist who used bearings rated to 15,000 RPM and the spindle bore was finished ground in situation with the bearings. The price I paid also includes the pneumatic drawbar setup and Tormach R8 collet which is ground flat on the bottom.
                              Hello!

                              Isn't that what GlockCNC has as options on its ordering page for the R8 headstock.
                              i.e. better bearings and balancing options - with a bigger price tag to go along with it.
                              Are you sure the guy you purchased your custom headstock from wasn't just a reseller.


                              Bearing Choices :
                              1) ABEC-5 Deep Groove Bearings - Included
                              2) ABEC-7 Sealed Deep Groove Bearings Instead of ABEC-5 Angular (+$247.00)
                              3) ABEC-7 Sealed Angular Contact - Optional (+$397.00)

                              Balancing :
                              1) Spindle Arbor Balancing to 15,000RPM Included (+$79.00)
                              2) Spindle Arbor Balancing to 25,000RPM (+$120.00)

                              Pulley Options :
                              1) 2 Step 5 Rib Pully (40mm + 60mm steps) - Included (+$69.00)
                              2) 3 Step Sherline Compatible L Size Pulley (+$69.00)
                              3) I'll Make My Own, Don't Send a Pulley

                              Adapters :
                              1) Taig Mill Adapter (+$99.00)

                              Drawbar :
                              1) Drawbar Included (+$20.00)


                              Originally posted by RB211 View Post
                              The Tormach 440, even at 8,000$ would be a huge improvement over what I have ended up with, for not much more money.
                              As you can see, I am still not done paying money to get my Taig working to my satisfaction, why I am suggesting to you that you just buy a Tormach. I wish someone told me what I am telling you.
                              Alright br0ther. I am going to give your advise some serious thought before I make a choice.
                              A CNC mill seems to be the most important piece in a metal workshop.
                              So it makes sense to invest in a good one up front.

                              Its just that I wasn't expecting it to eat up 80% of my home machinist workshop budget.
                              I still need to purchase everything from tables, lighting, enclosures, vacuum, tools like bandsaws, grinding wheel, dremel...etc.

                              Despite producing machines for decades,why hasn't the Taig company addressed the issue of hassle free, rapid R8 tool changing?
                              I wish I could rent an existing CNC Taig out for a couple of months and see how much of a hassle re-calibrating the Z axis is.

                              The last thing I'd say is that there is a gap in the market for good quality "hobbyists" CNC mills between $3.5K and $8K.

                              Comment


                              • #30
                                Originally posted by epicfail48 View Post

                                3d printing and CNC machining are only similar in that they both use g-code. Knowing how to run a 3d printer woont help you with a mill, because again, its not just the programming. Its the fixturing, knowing what tools to use when, knowing how to keep a part from being turned into shrapnel, preventing the tool from destroying itself, planning out the sequence of operations to make sure that one operation doesnt take away your ability to fixture a part for the next operation, knowing how different metals behave under the cut.
                                The only way I could possibly learn it is by doing it, mistakes and all.
                                Hopefully I won't do myself in while trying to learn it @ home.

                                The perfect solution is to do a bunch of courses for a few semesters at a local college (after this Covid situation is under control), find a master machinist to mentor me and then and only then purchase my first CNC mill.

                                But what's also true in many cases is that tomorrow never comes.
                                All the best laid plans often come to nothing on account of waiting and waiting.


                                Originally posted by epicfail48 View Post
                                BEFORE dropping $10k on something you dont know how to operate. Take a class, sign up for an apprenticeship, whatever.
                                Learning by doing sounds fantastic until you destroy a machine with a hard crash, or worse, injure yourself with it. Again, i strongly recommend that you reconsider going out and dropping that much money on new tools until you know the basics of how to use them. Mills and lathes arent like printers and plastic isnt metal. Theres a different skill set there, and a whole host of problems youre sweeping away because youve designed complex parts
                                Believe me, I'm a saver not a spender.
                                I hate the idea of spending - and even more so on things of which I have limited knowledge.
                                But I equally hate the idea of making big plans and accomplishing nothing.

                                Given that classes at local colleges (might or might not) start in the Fall and I can probably only handle 1 course per semester with my full time job, what do you recommend I do to expedite my CNC learning?
                                I don't have anyone I can hang around with who is a machinist.

                                I am doing all i can to absorb info off Youtube videos, forums, beginners books..etc.
                                But at some point, if I cannot try out all that theory on a personal project to learn, i may as flush it down the toilet.

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