Friday, 12 September 2014

CNCing About.... Part 1

Hello :o)

A few years ago I went into a sort of partnership with a guy called Steve from the Oxford 2mm group. The deal was that he provided the milling machine in the form of a Proxxon MF70 and I would supply the CNC conversion kit. I purchased a conversion kit from a company called USOVO and the mill was duly converted by Steve. It was then passed onto me to finish off the conversion and get the thing working.

Roll on a couple of years and after not touching it I decided to get it out of the cupboard and try to get it working as it seemed too good to hide away unused. This is where another guy called Robert stepped in as I just couldnt get my head around the electrical connections and configuring the Mach3 control software. Robert took the mill and promptly got it working in about an hour and it was then back to me to finalise a few settings and tweak it until it was happy.

Anyway, its all up and working now and I am one happy bunny. Even better I found a plugin for Autodesk inventor which creates G Code based on my 3D models. It even does a nice little preview so I can check to see if everything works how it should.

Even with this preview, it still took a bit of 'tweaking' to get the machine cutting right though..

Eventually it all came together..

And now I have four chassis sideframes for my PECO 22xx collett engines on my 'to do' list..

Thank you goes to Steve and Robert in helping get the machine to this stage. The trouble is now what can I do with it next....

Julia :o)


  1. Is that double sided copperclad your machining there Julia?
    The preview function certainly is usefull, in the short stint that I did CNC programming (Fanuc system on lathes, I hated it!) the graphics function was invaluable, not only to check that the program worked but to make sure that the tool path didn't stray too far towards the chuck!
    Check out Brian Madge's OO9 range - his kits feature CNCed crossheads, slidebars etc.

  2. Hi Paul.

    Yes it is, its 0.5mm double sided copper clad board. I have built a few chassis using it so far and it helps with the electrical isolation.
    Many years ago in the (good) old day I used a Heidenhain system on a mill and I used to be able to program it line-by-line off the top of my head but now you can get so many nice little programs and plugins which do it all for you. It makes producing G Code so easy its hard to ignore. The most used button I used was the feedrate dial, Indispensable when you had a new program and you wanted to control or stop it without resorting to the emergency stop button.
    Brians stuff sounds interesting, have you got a link?


  3. Here's a link to Brian's mill. page:

    G codes - I'd forgotten about them. I really hated programming and only learn't under sufference and the promise of a pay rise which never materialised. I no longer work in machine shops, all of my machining now is for myself (and a select few others) and done on the dining table!

  4. Thanks for the link Paul.
    Im pretty much in the same boat, I bet you find it far more enjoyable now, I certainly do.

    J :o)

  5. When I finished working in machine shops (redundacy) I'd had enough, not only of lathes but of the kind of person that owns and runs small m/c shops. And, oddly enough, I really disliked turning anything under 50mm dia., even going so far as to turn down a job as it involved small work, nowadays I really enjoy making small parts on my Unimat. And I long for the day when I can set up and use my Grandfather's pre-war Myford.

    Anyway, keep the posts coming!

  6. Like the vid Julia, but there seems quite a lot of bend in the bit @ 1:15 does that effect the accuracy? Looking forward to more postings here.

    1. Hi.
      I see what you mean but I think that is the result of camera distortion rather than the cutter physically bend. The cutter is solid carbide and from my experience they snap rather than bend, its only cutting 0.5mm thick PCB too at a quite ow feedrate so its not really under much stress. The parts have come out reasonably accurate with only 0.1mm error over their length which I have put down to the accuracy of the machine. Thanks for pointing it out though, its worth keeping an eye out for things like that in the future.

  7. Super stuff as always Julia! I can see this being useful for buildings as well as rolling stock, mainly producing the basic shell components (walls, roof etc) to the exact dimensions required.

    1. Hi Tom.
      My mind is working overtime at the moment thinking of things to use it for! Engine chassis are the obvious choice but I am also currently thinking of gears too. Profiling things are easy to do so yes, buildings could be done too. If there is anything that you need then let me know.
      What was the RMWeb show like? I have heard it was a bit of a flop? I hope everything went well for you though and Ropley performed well?

  8. Thanks Julia.

    Attendance wasn't good for RMweb Live, that is true, but I think the choice of weekend was probably the cause. Sunday was busier than Saturday but I think there were simply too many other events on that weekend.

    The actual format of the show has a lot of promise and I understand they are going to do another one but are thinking about moving it to earlier in the year, possibly January, to avoid another clash like this.

    One area that was very interesting was the 3D printing demonstration area. Hattons were scanning visitors and then printing them out in miniature and it was good to see the process up close. I still think it has a little way to go yet before it becomes fine enough for 2mm, but it's heading in the right direction. Andy had an example of a lovely looking tree frame made up using one of the pen devices that "writes" with plastic and I can see a lot of potential in that.

    I was really pleased with how Ropley behaved all weekend. No major failures and only a couple of areas I need to take a look at trackwork wise. It proved I can transport, setup, operate, and brake down the layout myself, but preferably it needs two people for comfortable operation. If nothing else, the show made me get the layout fully operational, and now i'm not worrying about still having fiddle yards to build I can really focus on getting the scenics moving again.