If you need to start machining from scratch it might be beneficial to start with a manual machine to get a sense of "how to make chips" and feel the cutters and materials. You can always convert it into CNC, later. Besides the Industrial Hobbies machine I posted above, which you can buy as a manual, and then purchase from them complete conversion kit (you could save some $$$ here), you could also look at Microkinetics kit for RF45 machine. It uses steppers, but on the other hand, there is nothing wrong with that. It comes with their own software, but you probably could get from them the mechanical kit and then use with Mach3:
http://www.microkinetics.com/conv_kits/index.htm
Note of warning: don't get a round column machine (like RF31 or its clones). If you decide to go with Chinese get the one with dovetail square column, like RF45, which is also sold by many vendors by different names, but carrying the "45").
What you also need to know and consider, those machines run only up to some 1,500 RPM. Even if you put a 220V 3 phase with VFD you still won't be able to get much more than that because the spindle bearing is crap. For engraving you will need at least some 10,000 RPM. To my knowledge, from affordable options only Bridgeport M-head would give you close to that. It is MT2 taper, so limited only to 1/2" tool bits (unless you use ER32 or ER40 collets with MT2 adapter).
For engraving many folks make a quill attachment to hold much faster (water cooled) spindles with VFD. I'd get a separate dedicated engraver if I were you (actually, I have two 8)), as it is much faster than the mill and you won't get into the hassle of changing spindles. If you look around sometimes you could find amazing deals. Friend of mine found Hermes Vanguard 3400 in perfect working condition for $300 on Craigslist (this is way less money even than a crappy Chinese spindle, alone).
All in all, for the mill there are plenty of options and DIY CNC conversion might also be a viable one (you can go to www.cnczone.com for more info on that one). If you want a nice and precise long lasting machine then there are plenty of older American made smaller knee mills, which could fit even in the basement: Rockwell/Delta mill, Johansson, Millrite, Clausing 8520, Hardinge TM/UM horizontal/vertical mill (you could even find one with fitted M-head), etc. Any of those could be found for under $1,000 and then retrofitted later.
Best, M
BR said:
Hey Marik
thanks for the response.
Those machines in your link look very good indeed.
My intentions are to use it primarily for aluminum parts for various jobs/hobbies as well as front panels for DIY. I have a great source for cases and panels, but if I was to have my own "engraver", it would be easier to build one-offs to testing purposes. Wood would be another hobby that I wouldn't mind using the machine for, on occasion.
I was trying to find something that would give me at least 19" for frontpanel work and I don't really see going much bigger than that. But, you are right, I could outgrow it, if the demand for bigger parts starts to come in.
I'm also a very curious beginner and I would have to learn machining from scratch and obviously have to think really hard before investing some much cash in a machine that will be used 20% for work and 80% for hobby in the beginning.
If I can get enough business lined up, I could even possibly convince the boss in the investment. But the CNC would have to pay for itself in the first year, in order for him to even think about it.
I also have a friend that has a very nice bridgeport that I could possibly invest in a CNC package for it, but he lives about an hour away, and I'm not sure I want to deal with the partnership.
Thanks for the link.. I'll surely bookmark it.
take care
Gil
