Custom building a CNC mill for aluminum

[JoeSalerno]

So as a quick background I've made a 3-d printer (I know a monkey could assemble one of those DIY prusas) and want to step up my game a little bit.

I came to the realization that some people have made/sold DIY milling kits, but most of them are for plastics or wood. I would like to make a small 1.5'x1.5'x10" mill that has the capability to cut softer metals like aluminum. I thought about just changing the tool and bit on one of these machines, but I'm not sure that'll work, let alone having to scale up their designs.

I guess my real question here is, how difficult would it be to make a mill, as opposed to building a 3-d printer? I have no problem cutting out pieces to make an acrylic frame with a laser cutter just like a 3-d printer, but from seeing other's design's, aluminum frames seem to be used because a higher level of rigidity is needed.

My main issue here is, what would I do for the electronics and rotary piece? Would it be possible to use a Dremel mount or something like that? It's probably easy to tell I'm really quite inexperienced in this, but I'm just asking to get my feet wet here. Any advice will be very much appreciated, thank you.

 

[Baluncore]

I guess my real question here is, how difficult would it be to make a mill, as opposed to building a 3-d printer?

Making a mill from scratch is a real challenge. The easiest way is to buy a used mill, then replace the lead screws with new ball screws.

One problem is knowing what you will use it for. How many degrees of freedom does the cutting head require. If you can make what you want in a mill then you can automate that mill. For aluminium there are single cut carbide burrs that cut fast with a good finish.

 

[Asymptotic]

David J. Gingery wrote a series of DIY books beginning in the early 1980s on how to build machine tools from scratch. As @Baluncore has observed, doing so is a lot of work; Gingery's books will give you an idea of just how much.

http://gingerybooks.com/

 

[CWatters]

As I understand it one of the problems is rigidity or rather a lack of it and it's effect on accuracy. Unlike a printer the cutting tool has to press quite hard on the work piece and that can cause the machine to bend and reduce accuracy. It's why many CNC machines are big solid lumps. You also have to work to eliminate any backlash in the drive mechanism.

 

[Dr.D]

Unlike a printer the cutting tool has to press quite hard on the work piece and that can cause the machine to bend and reduce accuracy.

This is certainly true, but I'd like to emphasize that this is a dynamic bending problem, otherwise known as a vibration problem. It is lot more difficult to handle than just a static bending problem.

 

[jim hardy]

Second Dave Gingery.
I've not read this one
https://gingerybookstore.com/MillingMachine.htmlbut his forge books were excellent.