14 Replies Latest reply on Nov 4, 2013 10:16 PM by David Martin

    CNC machining from solidworks

    Matt Conlin
      Do CNC machines use a type of program that is compatible with solidworks?
      So if I draw a model, will a cnc machine be able to understand the program/file?
      • Reply
        • CNC machining from solidworks
          Gerald Davis

          Matt Conlin wrote:

           

          Do CNC machines use a type of program that is compatible with solidworks?

          So if I draw a model, will a cnc machine be able to understand the program/file?

          I design parts that are manufactured with metal cutting lasers and turret presses (frequently with Fanuc controllers). I also send out parts for lathe, milling and EDM work.

          For those who do the CNC programming based on my sheet metal designs, I generate a slddrw that has no border - just a blank template. I scale it 1:1 and then save it as a DXF (or DWG) depending on the manufacturer's preference.

          For the machined parts, I simply save the sldprt as a STEP or IGS file.

          The CNC programming staff then imports the DXF (or STEP) into their programming system (frequently Gibbs, Striker, MasterCAM, or MetalSoft).
          • CNC machining from solidworks
            Matt Conlin
            I guess I should have also said that I am designing a mold for a plastic part.

            So if I save the mold part as a STEP or IGS file, the CNC machine will be able to read that program/file?
              • CNC machining from solidworks
                Anna Wood
                Matt,

                Talk to the people who will do the CNC programming for your parts. They may be able to read the SolidWorks files directly. Many of the newer CNC programming packages can read most major CAD vendors data directly. (MasterCAM, Esprit, etc)

                If they need something different in the way of a translation; parasolid, step, iges or dxf they will let you know what they need.

                Best to go direct to your manufacturer to see exactly what they need to do the work.

                Regards,

                • CNC machining from solidworks
                  Gerald Davis

                  Matt Conlin wrote:

                   

                  I guess I should have also said that I am designing a mold for a plastic part.



                  So if I save the mold part as a STEP or IGS file, the CNC machine will be able to read that program/file?

                  I don't think the general state of technology is such that the CNC machine will read the STEP file directly, although in some cases it can be done.

                  More generally, there is an intermediate process that involves a human being using software (e.g. MasterCAM) that translates your STEP file into a CNC program (also known as "posting") for a specifc milling machine. During this intermediate process, the human being (aka CNC Programmer) will specify the billet size, tooling, tool stations, fixtures, and clamping to hold the part.

                  The CNC program file is an ASCII text file that consists (usually) of a list of "G codes". The G codes are interpreted by the CNC mill's controller in order to position the table (XYZ), turn on the spindle, and move to the next point, etc.

                  The machine operator (aka Machinist) will follow the instructions provided by the CNC Programmer to load the tooling, clamp the billet, and upload the CNC program into the controller.
                • CNC machining from solidworks
                  Matt Conlin
                  Thanks for your suggestions.

                  We are looking into SolidCAM or CAMWorks
                    • CNC machining from solidworks
                      Gerald Davis
                      Both of those are good products, but why are you considering them?

                      Unless you're in the business of machining, you really should delegate the CNC programing to your tooling manufacturer. Even if you are expert in the tooling trade, it is unlikely that your CNC program will be of much help to them. A great deal depends upon the specifics of the available cutters and fixturing.

                      If you're just trying to shorten the lead time, then do as Anna suggested and meet with your tooling shop and find out what you can do in your design to expedite their work. Eliminating slides, simplifying parting lines, providing good spots for ejection pins and designing a part that fills uniformly with minimum pressure will impress them more than handing them a load sheet and G code dream.

                      I'm shooting in the dark here. You haven't provided much detail, so I apologize in advance if I've hurt your feelings.
                        • CNC machining from solidworks
                          scott brown

                           

                          If you're just trying to shorten the lead time, then do as Anna suggested and meet with your tooling shop and find out what you can do in your design to expedite their work. Eliminating slides, simplifying parting lines, providing good spots for ejection pins and designing a part that fills uniformly with minimum pressure will impress them more than handing them a load sheet and G code dream.

                          I agree .Being able to work directly with the engineer to make a part easier and less expensive to manufacture while retaining the desighn intent is a plus for everyone.I prefer to get native SolidWorks files .Being able to easily modify the model for machining purposes makes the programming for CNC machining alot easier and sometimes more efficient ,especially when there are alot of 3-d surfaces.I think some don't like to send a model that has multiple configurations possibly due to a chance the wrong part will get built.In that case I would prefer a parasolid.
                      • CNC machining from solidworks
                        Matt Conlin
                        Thanks again. We do not do the machining in house, so I will talk to the company that we will deal with and figure out what I can do to make their job easier.
                          • CNC machining from solidworks
                            Anna Wood
                            Matt,

                            Good move.... You will learn a lot from them.

                            There is so much to the world of manufacturing. For me it is a constant learning curve with incremental process improvement with every new project we take on.

                            Regards,
                              • CNC machining from solidworks
                                Dan Mills
                                As a person that does our tooling design and a majority of our CNCmachining, I can say that leaving the machining up to the toolingcompany is the way to go.

                                There are a lot of engineers that do not understand how to designfor manufacturing.  We ran into this issue quite frequentlybefore I took over the design of our own parts.  

                                My suggestion to you would be talk to the tooling people, see whatthey say you can do for them from a model standpoint and go fromthere.  
                                  • CNC machining from solidworks
                                    Larry Kutcher

                                     

                                    Originally posted by: Dan Mills As a person thatdoes our tooling design and a majority of our CNC machining, I cansay that leaving the machining up to the tooling company is the wayto go.   My suggestion to you would be talk to the toolingpeople, see what they say you can do for them from a modelstandpoint and go from there.  



                                    For sure!
                                    For every machine shop I use I've sat down with 1) the owner 2) themachinist that will actually be doing the cutting 3) shop/ floor,steward/forman "if hes not the owner". Review what theyare capable of, what they like and what they stay away from. Get toknow each shop for their (+/-)...

                                    *Make sure all of them know exactly what you expect.
                                    *Make sure YOU know what they expect from you. I also provide a setof prints that call out tolerances, surface finish etc. A set ofcompany standards and practices and go over it all face toface.

                                    Make sure everyone is on the same page right from the beginning andthere will be allot less heartache...

                                    -Kutch


                                      • CNC machining from solidworks
                                        Dan Mills
                                        Great points, Larry....Couldn't agree more!!
                                          • Re: CNC machining from solidworks
                                            Charles Davis

                                            I used to operate my own prototype machine shop, and agree with Larry's advice for working with a machine shop.  Different shops have different capabilities and types of work they do best. It's important for both parties to understand exactly what the specifications and expectations are before starting work.

                                             

                                            Unless you have a lot of experience designing parts that get machined, I'd advise you to go over the part with the machine shop owner or CNC programmer. Ask them if they have any advise. Listen carefully to what they say. Sometimes a small change in the design that does not affect functionality can save you much time, money, and frustration. This will make you a far better designer over time.

                                             

                                            More companies are moving to Integrated CAM: CNC programming software that runs inside of SolidWorks. This means you can give them the SLDPRT or SLDASM, and they can machine directly from that. This has the following advantages for the engineer: 1) The shop has complete knowledge of the design intent (threads, tolerances, material). and 2) If you change the design, often those changes can be updated by the shop automatically or with far less effort.

                                             

                                            Here is a very basic overview of how it works.

                                             

                                            http://www.youtube.com/watch?v=rN8kWQ2cutM

                                             

                                            If a shop is not using Integrated CAM, you can often supply them with the SLDPRT because a lot of systems do have import capability, though often they will loose the history tree, and in all cases they will loose the feature-machining path associativity. My second choice would be an X_T file, after that STEP, then IGES.

                                             

                                            Some engineers do machine thier own functional prototypes. This is becoming more common because, in certain cases, it can reduce costs, improve turn-around time, protect IP, and improve design. However, you really need to think carefully before taking that step. Machinists are highly skilled tradesman. Owning and operating a CNC machine is usually a lot more expense might be first expected (think expensive car payment, or cheap house payment). Making anything will usually take at least 2x or more longer than you think.

                                             

                                            Yet, sometimes getting a little Haas mill and cranking out your own functional prototypes can make sense, 1) If your parts are relatively simple, and made of easy-to-machine materials such as aluminum, polycarb, mild steel. 2) If you do a lot of them. 3) If turn around time is important. 4) If prototecting IP early in the design process is important. 5) If you are mechanically inclined. 6) If you have the time to devote to it.

                                             

                                            Here is a book I wrote to help engineers better understand machining processes and to help them begin machining thier own parts.

                                            www.cncforengineers.com

                                             

                                            I hope this helps. Sorry for the plugs, but this is what I do which is why I feel qualified to advise you.