Hi, I have no experience at all with CNC machines, and very little with hotwire systems, but after watching the OX build videos, I think I can do this. Basically, I'm thinking of either building an OX with two independent Y-towers, and no Y-axis, or building two XY tables (V-slot) and mounting these to MDF bases. If I understand things correctly, either of these should do the trick, though the XY tables as described on this site look far simpler. Just two 20x80 rails riding on each other, and moved by a circular belt. Two of these rotated so that the secondary axis becomes a Y-axis would seem to be sufficient for a hotwire cutter? I already have the hotwire power on hand, and own both Profili Foam and Sketchup. I have some basic 2-D CAD experience. Currently I am generating DXF files which I get CNC routed by a mate, and then do manual hotwire cuts from these templates. It is time to enter the 21st century, I think. The plan: Place an order for the entire OX BOM Start building Ask lots of questions here on the forum Take lots of pictures to document the build Some specific questions: If I go with the two XY tables would this seem feasible for a hotwire cutter? Am I correct in assuming that if I get the CNC USB controller, that this will be all I require to run the machine? I will feed it the necessary DXF files, of course. Finally - I'm based in Brisbane, Australia. I understand that there is an Openbuilds depo in Perth. However, some of the bits in my BOM are currently out of stock - though I'm not sure if this is just in Perth, or globally (eg: 1500mm 20x80 rails) Thanks in advance for your interest and your help. Regards, Duncan
I'm not sure an OX package will provide the best (or most economical) use of the materials. Going back to the sketch you saw yesterday, may offer a simpler approach. It would also allow you to transition to a four axis setup as your abilities grow.
Hi, You're right, of course. I need bringing back to reality from time to time I think. My problem is never actually having seen one of these in real life. The simple arrangement in the picture above looks more than adequate. It is basically just two XY tables set on end isn't it? However, I would need 4-axis from the start if I want to cut airfoils. Care to offer a suggested BOM? Thanks for the sanity check. Regards, Duncan
Hi, Thanks for taking the time to reply. It is 12.30 here at the moment, and I'm off to bed. Catch you tomorrow morning... I need to cut wing blanks with a 1100mm chord. Span of 914mm. So that means X-axis cutting length of about 1200mm, Y-axis of about 1000mm. Z-axis need not be more than about 200mm Maybe 500mm to make sure I cover all possibilities. Duncan
Hi, After spending some time reading through the Mini V linear actuator build, it looks like this may be the answer. This looks like a really simple arrangement, and well within the budget. Since this is a hotwire cutter, there is very little need for a robust construction, and I think that two 1500mm X-axis linear actuator rails, mated to two 500mm linear actuator towers would be more than ample for my needs. Attach 4x Nema 17 stepper motors, and run the setup using your USB controller. And that's about it. All up cost just on $800. That certainly sounds like a do-able project. Am I on the right track? I am not that clear on how the CNC USB controller works, however. The web site says that it is a complete hardware/software package, and that additional software (eg: Mach3) is not required. But I can't find any detailed info on how this interfaces with the computer, and a definitive overview of how it works. Can you help with this? Regards, Duncan
Mechanically, you appear to be on the right track. As for the electronics aspect however, you're gonna need one of the electronics geniuses to chime in for help with that. Google may also be helpful.
Hi again, I get paid in two week's time, so that gives me some time to decide on a build. But the more I look at it, the more I'm thinking that I'm headed in the right direction. I read the USB CNC controller manual today. Seems pretty straight forward. Yes, I think I can do this. Duncan
Hi Duncan. Have you tried these people. They have quite a bit to say regarding the USB Controller. Some good videos as well. http://buildyourcnc.com/ Cheers Gray
Hi, I have the physical BOM sorted. And I think the USB CNC controller is the way I'll go. But I'm still uncertain about the stepper motor driver arrangement. Is this a separate board? Software? And where do I get this? My understanding of the flow of control is as follows: I generate DXF files on my laptop using my current CAD software These files are fed to the software supplied with the USB CNC board This board then passes information to the stepper motor driver board The Hotwire cutter springs into action. Would this be accurate? Duncan
Hello Duncan, Upfront, I have not built a CNC hotwire as of yet so I can't offer too much help in this area. But I do know you can import DXF into CNC USB software and you can set it up as a 4 axis machine so with the workflow you show, it should be doable this way. Your best bet would to be to ask this on the CNC USB controller forum and see what the guy there say about it being done this way. http://forum.planet-cnc.com/ Please let us know what you find out so that others can learn as well. I did find a person foam cutting with CNC USB controller and a separate software for wing generation called Profili Pro http://www.profili2.com/ Hope this helps, looking forward to your build. Mark
