Ask the Machine Whisperer?

March 19th, 2019

From Eric in Michigan: Hi Steve, we’ve been reading your blog and it has led to a debate in our shop about what the term “DNC” actually means? I was taught in school that it means (direct numerical control), describing the spoon or drip-feeding of programs too large for the machine memory, into a CNC control. My colleague maintains that the term “DNC” is now accepted to mean (distributed numerical control), describing the direct connection between a software and a group of networked machines using that software to transfer CNC programs. Can you please help us settle the debate?

Steve: Hi Eric, thanks for reading our blog, I’m very happy to hear that it lead to this conversation in your shop. I’ve maintained for years that DNC systems aren’t covered enough by Tech schools, and that has led to a lack of DNC knowledge in many shops that I visit. There’s no lack of knowledge to be found in your shop however, as you are both correct! DNC (distributed numerical control) means a file management system to control and facilitate file transfers of CNC programs.  While (direct numerical control) means to drip feed the program from a computer to the CNC control because the machine does not have sufficient memory to run locally.

From Sean in Pennsylvania: Hi Steve, probably because I’m a big fan of everything Apple, I happily noticed on the blog homepage that you’d also welcome Apple-related questions. Due to the security advantages of Mac vs Windows my company exclusively uses Mac computers. My question for you is will Windows Parallels on a Mac be enough computer to host your Windows-based eNETDNC software?

Steve: Hi Sean, thanks for the question and yes Parallels will work great with eNETDNC, we actually have other customers running eNETDNC this way.  I am a big Mac fan myself, and run it this way on my computer everyday. Don’t forget about the Apple event coming up on March 25th, can’t wait to see what’s new!

And we’re off!

March 12th, 2019

Well, here we are in our 3rd blog post. We’ve laid down the groundwork, and now it’s finally time to “Ask the Machine Whisperer”. I will setup each question with the name and state of the reader asking Steve their question, and then follow each question immediately with Steve’s response. If you have a follow-up question related to today’s blog, or something new to ask the “Machine Whisperer” please let us know on the “Got a Question?” page of this blog.

John from Wisconsin: Hi Steve, if I have an active ethernet port on my new CNC, do I really need to connect it to a DNC system? Can’t I just put the machine on the company Ethernet network, so I can easily access my CNC programs that are stored on the server, right from the control?

Steve: Hello John, you can directly connect a CNC machine with an active Ethernet port directly to your Ethernet network, but it’s not necessarily a secure network connection or a robust file management system. It depends on the machine, as on some windows-based CNC machines the Ethernet port connects just like a computer on the network and the machine is mapped to a specific mapped drive. These windows-based CNC machines most likely have no antivirus to protect the machine from a virus off the network, and most machine manufacturers say not to load antivirus software onto their machines. Now there are other brands of Ethernet-capable CNC machines that will have secure file-transfer protocols on them such as FTP or CAPPS, and would need an FTP server or CAPPS server running on your network to talk to your machine. This type of Ethernet connection is always safer. Besides network security, the other big risk I see with direct Ethernet connections is with file revision control for CNC programs. With a direct-connect method you are most-likely pointing to one directory on the Ethernet network for downloading/uploading your CNC programs. This can unwittingly give Operators the power to upload edited programs from the machine, overwriting the proven programs in that directory.

If you only have 2 machines in your shop, and they are both Ethernet capable machines, you may be able to design a direct-connect method that works for you.  But most shops not only have more than 2 machines but most likely also have machines that are not Ethernet capable. A big advantage from connecting an Ethernet capable CNC machine to a DNC system is that you can have one software communicate to all your machines old and new, this would include RS232 ports, Ethernet ports, and USB ports. DNC software can also log every program uploaded and downloaded, and send an uploaded edited CNC program to a dedicated “updates folder” in your directory, until a Programmer can review it. Also, automatic file compares can show you the differences between your original files and changes in new uploaded edited files, and can control who has access to proven files and files sent back to the server.  I hope that helps!

Mike from Texas: Hi Steve, I’m curious if over all the years you’ve been networking machines, have you found a specific brand of CNC machine as the easiest to set up on a DNC system?

Steve: Hello Mike, this is a tough question, once you hook up a machine you’ll find hooking up another one of the same kind to be much easier, but if I had to pick one I would say Fanuc controls because I run into so many of them and hooked up to every type, so I feel that I could do them in my sleep.  But my best answer would be to buy the best machine for the type of work you’re running on it, most modern DNC systems will talk to any brand of machine.  Thank you.