Cheap CNC Mill ?

Cr2348455 said:
If I were going for cnc, I would want to mill steel as well as aluminum.
I bought a manual Legacy router sled , used it a few times, just to lazy to think about all the setup.
If I had the cash, I like Tormach.
That said, I would like something much smaller but with ability to mill in 3 axis.
thanks to all
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I recommend a conversion of a G0704, PM25, or ideally a PM-940M. More rigidity and cost at each tier there. You should be able to keep the machine and CNC conversion under your $6k budget with moderate ease. The PM-940M will leave less room for tooling purchase.
 
G code is a fairly simple language, at least for rudimentary programs and one can create G code programs with a simple text processor like Wordpad. This will enable one to cut simple arcs, move in straight lines, drill patterned holes. etc. A 2D CAD package will facilitate creation of the programs. A 3D modeling program, along with a CAM program will permit creating complex shapes in two or three dimensions. A CAM program alone can import 3rd person solid models and ceate G code to make copies.

As to the actual hardware, there are basically three ways to go; convert a manual machine to CNC, buy a used CNC, or buy a new CNC. What your expectations regarding performance will govern the decistion about how much machine is needed. You can buy several new machines like the Sherline for around $2K bit they are light duty. A more substantial machine would be the Tormach PCNC440starting at around $5K or the PCNC770 for $8K. Adding bells and whistles can triple those prices. The PCNC1100 is the next step up but you are getting into a industrial machine price range.

I chose the 770 nine years ago. The 440 wasn't available yet but I still would have gone the 770 route anyway. The package that I chose was around $14K at the time, probably closer to $16K now. A PCNC1100 package would have added another $2K but the deciding factor was available space.
 
Here is something that will generate G-Code for you with just inputting the sizes and spaces you want. You can do many things without learning a full CAD/CAM program.

Newfangled Solutions Mill Wizard

www.machsupport.com www.machsupport.com

You can get what you are looking for at your budget.

Avoid small mills like Sherline and Taig as too small and lightweight (Your decision but be sure to see one of those in person before buying.)
 
Thanks for all your generous information.
I have a Sherline 2000 mill, and it is just too small.
That is why I got the almost 1000 lb Grizzly mill.
J
 
I have a Brother TC-225 with a conversational control. I absolutely hate it. My background is FADAL, HAAS, and some conversion machines with FAGOR. G-Code. Oh how I love it. Anywho, So because of the early 90s age of the machine I'm unable to find a post processor for this beast. So throw out the cad/cam and must converse with the beast. It's reference work plane is the bottom of the part. The tool plane is based off of a 3" block from the table and you basically program it by telling it what to do last first. Picked it up for 5k used. I do on the other hand like the rigid tap feature.

Sent from my SM-G950U using Tapatalk
 
cr234 - what you want to do is possible. I picked up a Bridgeport VMC 1000 for $5000 CAD, it needed a bit of work, but not too much just to make chips (beware that machining is an endless way to suck a little more money, one tool at a time). There are good post processors for my machine, DX32 - but I have simply stuck with coding directly. I appreciate that the real power is in doing the solid model and programming too paths, but as a manual machining guy for many years, pretending it is a manual machine, except instead of cranking a handle, I just send a line of code - is really awesome. I am steadily building ever more involved programs. Even though I'm a total beginner, it is not difficult to get to the point that I'm doing things that would be much harder to do on one of the manual milling machines. For example I made some two piece jaws for a big 3J chuck - I know it is possible to generate a good approximation of the scroll teeth on the back of the jaw using a manual mill, but it is a lot of work. On a CNC it is two lines of code to create the shape, then repeated 8 times with the origin translated - so I made two full sets of the jaws.

Getting an old industrial machine (this one I got is a 1998) means there is lots of capability, heavy, rigid, plenty of power, full enclosure, flood coolant, tool changer, 4 axis. It does take up quite a bit of floor space, but then you didn't say that was a problem and it just fits in with the capability of my residential electrical supply. You also didn't say that power was a problem (you can expect that you will need a good 3 phase system). So I suggest you start looking around, learn what you local used market is like (it took me about 3 years to find this VMC - I looked at quite a few and passed them by, but I learnt from every one of them).

Be patient, start looking. What you are thinking of really is out there.
 
Thank You Chipper,
I do appreciate your great advice. I have a few machines that are 3 phase, so I do already have a rotary phase converter.
C
 
The rotary phase converter may be okay. I ran a Willett Add-a-Phase (rotary) for about 35 years for my first several machines (including the 575 ones via a transformer) - never had an issue. When I got serious about the VMC, I had a few recommendations that powering the CNC of that vintage off an RPC was a bad idea. The idea being that if the power quality issues inherent to an RPC were to degrade any of the electronics - that may contribute failure. Certain critical components are not practically repairable - it is easy to gobble up $20K in a repair, the machine after the repair would still not be worth $10K (prior to the repair it is just scrap metal). That advise gave me the excuse to get a PhasePerfect - and it is awesome (all the machines appreciate the upgrade). The PP cost me as much as the whole CNC machine plus the cost of a commercial mover (the seller insisted on my using a commercial mover when in his facility).

The point being that you should do your research on what you need for power. Some machines will accept a single phase input, some will likely be fine on the RPC, others may need something better.
 
Thank you
I will heed your advice. I need a whole bunch more learning to do before I sink a dime.
 
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