Hi guys, well it's been a while since I came here, after I built my cnc router and had many ideas of converting my ZX4570 I decided not to go with it since I really like to have this manual mill it's very handy.
So no I decided to go big and build a VMC. I'm here so you guys can advise me on some stuff. Machine is intended to cut aluminum alone but I want it capable of processing steel, stainless and some titanium.
I've done most of the design, still need to wrap some loose ends but I think I pretty close to final.
I need the following XYZ travels: 600*300*420, I'm going with Hiwin HGR30 rails with HGW30HC blocks in all 3 axis.
I'll be needing rigid tapping so I'm gonna buy a 3.7kw servo motor for the spindle and I'm gonna buy a BT30 spindle ATC capable (intend to make an umbrella ATC in future), motor is 8k RPM max a bit low for my taste but not too bad... I'm still deciding if I'll get a 12k capable spindle so I can gear the motor - need your input here.
Ballscrews I'm not sure yet... I was sure they would be 2005 on XY and 2505 on Z (P2 grounded) but here's the thing, this machine would deserve some 1kw servos but it happens I've 3 brand new (with 2 years old in the box...) 8Nm closed loop steppers here that I bought when I first intended to convert my ZX45, for using steppers I would preffer using 10mm but there are no 2010 quality ballscrews so either I need to go to 2510... so what you guys say here? price difference of the ballscrews is about $300 my design is made with the 2*2005+1*2505 need to change the design to go with all 2510 but nothing too bad... if I change to 2510 and later I decide to upgrade to servos will they work well with the 10mm pitch or will be too high? or should I stay with the 5mm pitch and later get the servos.... decisions decisions....
about the controller, at fisrt I was thinking mach3 with an SmoothStepper but I'm so tired of mach3... then I thhought to give a try with LinuxCNC and mesa cards but I don't think I going that road either... now I'm strongly thinking to get a chinese CNC1000MDb really like the style and looks very nice, gcode is similar to mach3 and functions is about what I need. it's ATC capable, rigid tapping capable, support 4 axis (actually I'll be buying the 5 axis one so I can use a 4th rotary axis and the 5th for the ATC in umbrella)
body, as the title says I'm going with epoxy granite so I'll need to have the design done as complete as possible so I can make the casting as perfect as possible. anyway here're some pics.
also need so advise on the way covers don't know if my design will work well, I might need some kind of support under them but that will be esily done if needed.
I'm aquiring some very precise tooling so I can square all axis as perfect as possible, I just ordered a large AA granite square to be the master square, already have a 750mm AA granite parallel, a few 0.001mm indicators so I should be able to get this pretty precise.
dimentions, the base is 500*1125*250 weight should be ~300kg, column is 330*500*1125 about 300kg also, sadle is 350*1050*120 about 100kg, the table is 350*620*60 about 35kg. I intend to have some steel bars placed in the castings so they can be machined flat to hold the linear motion stuff. I'll take the blocks to a friends cnc shop where he has large high end VMCs and willmachine the blocks as I need.
also need some advice to make an alignment system to the column, I was thinking to make some attachment plates at the column base and place 4 set screws (one each outside corner) so I can easilly square the column, than lift the columen and place some super strong epoxy (like jbweld) joining the pieces... the problem is if I need to disassemble the thing later... either for moving or re-align the column... also though about waxing one of the sides than apply the epoxy and join the pieces so it only would glue to one of the sides that way I could separate the 2 parts... I don't know yet... this might be to soon to worry with this...
for counter weight I'll be using an air cylinder, I think it's the best way to go...
the table will also be epoxy granite, I'll leave a smooth epoxy layer that I can self machine flat when the machine is done and have some placed pilars that I'll drill and tap so I can add a aluminum/steel plate with holes and threads to hold stuff.
anyway, here're the pics... please le me know what you think.