Hello every one . I’,m in the process of building a CNC 3 or 4 axis, and plannig to get one of those chinese all in one sets, the working area ideallly would be to cut 4 x 8 feet material, so my big question is : which nema motors , controlers and power supply, should I get… I plan to use this equipment on a regular basis, aprox 4 to 6 hours daily, every comment will be appreciated and gratefully received.( I’m located in Peru then my aquisition has to be the right one because of the imports are kind of complicated)
I’m confused… don’t those “all in one sets” come with motors, controllers, etc… junk, but still they are included… or am I looking in the wrong places?
What motors you need will be determined by what other kind of linear items you use (your guides, and actuators), and the performance requirements you set.
A big machine like that you may want to go with a belt, chain, or rack? But once you have other elements of your design there are formulas to figure out precisely what kind of motors you need. Of if you want to skip all of that just get the strongest stuff you can afford, and wing it.
Something in about the 425 oz/in range, or up, should do you. Also, servos are coming on strong anymore. At some point they become worth considering.
Hi, Oscar the processing area is important for choice of engines, but I think that type of material to be processed would be but decisive for the choice of engines, but in any case a work area in these dimensions 122x244 cm, I think motrores not smaller than 15kgfcm.
Hi Ricardo thanks for your comment, regarding material , will work with wood products (Plywood, MDF, OSB, Particle Boards, (3 TO 18 MM THICK) PLASTIC LAMINATES (FIBER GLASS AND COMPOSITE , ACRILICS and metal Cooper, and aluminum up to 6 mm. those spec for the motor Nema 15kgfcm.do you mean Nema 23 // thanks
Hi Paul , To start .I will be using 1/2’ treaded rods (32 tpi) maybe later will use linear bearings,what do you mean " actuators?"thanks for your kind help.
oscar
@Oscar_La_Fuente
You need to think things through carefully while you design your machine. You need to set goals, then figure out how to achieve them.
For instance, how long do you want to wait while your machine travels the limits of your long axis? Like what is an acceptable time for you? A minute? Then you would need to run 96 inches per minute to achieve that.
Now to go that speed using 1/2X13TPI threaded rod you would have to drive that rod 1,270 RPM which is pretty fast to turn an eight foot long length of 1/2" threaded rod. You should chuck a length of rod into a drill and spin it, just to get an idea of what you’re dealing with.
I use far shorter lengths of 1/2"X10 TPI acme rod and I know what it is like spinning it. Thin rod at high RPM can whip around at longer lengths. That whip is something you are going to have to take into account. Or perhaps even avoid, by using something other than 1/2" threaded rod.
If I were you I would explore the option of using some kind of chain drive. That would be more practical.
Check out Frank Howarth videos on his CNC build. About the size you at looking at. Used Gear drive that looked good for that size. Would be concerned at such long length threaded rod would need to be stiffer. https://youtu.be/5ThZws-858M