[Brentoxicated]

Hello everyone, My name is Brent and I'm new to CNC and this board. I want to build 2 machines as inexpensively as possible and was hoping to get some advice on what components to use.

The first machine would be a router-powered machine used to cut out wax molds for metal casting in a lost wax investment process. It may be used to mill plastic and light materials, but primarily wax.

The second machine would be a heavier duty mill similiar in capability to a Bridgeport mill. It would be used for machining the end product/parts from the casting process.. mainly aluminum motorcycle motor parts, so getting close tolerances would be a necessity, as would some sort of manual control.

I'm looking for advice on what ballscrews, steppers, controller boards would be good for both machines, one cutting wax and one cutting aluminum and steel. I'd like to get the best resolution possible.. but also best bang for the buck.

Also- for the heavy mill: what size spindle would you suggest? with the idea of machining aluminum and steel, and finding inexpensive compatible tooling.

Any and all info and advice is much appreciated. Thanks for your time.

[jm82792]

How big are the models you wish to mill out of wax?
If they are under one SQFT I suggest John's BBox kit if you want to build something without working from scratch.
It includes most of the mechanical parts, you merely need to cut the MDF,
and order the Thomson shafts from MCmaster.
It can be build for well under $500 for the frame, you'll have accuracy, rigidity, and some decent speed for soft materials.
I have his A4 and it's a very nice machine.
BBX...Design and Prototyping
For metal working I'll let someone else chime in, I've never milled metal before

[louieatienza]

For the wax CNC, I would just check the builds here, and the stuff made with them, to see which one suits you best. Not too much cutting forces involved so you should be able to build a pretty accurate machine rather inexpensively.

For the metalworking mill, I would suggest you check the metalworking section and see what is built there. Basically, you are not going to find a spindle that will cut steel effectively or precisely and still be relatively inexpensive. For that matter the linear components will be expensive as well if you want precision. I would suggest finding a used mill, and retrofit it to CNC control. There are many threads of just this in the metalworking section project log subforum.

[Brentoxicated]

jm82792,

Thanks for the info! I will check out that kit. I would be milling stuff slightly larger than 1 square foot, but not by much, motor cases and primary covers,etc.

[Brentoxicated]

louieatienza, Thanks! Yes, I will do some more research into machines on this forum as well as retofitting.

[wizard]

Machining wax should be fairly easy to take care of with a simple router. You could probably get away with a machine driven with timing belts.

The bigger issue is what do you mean by motor cycle parts. There is a big difference in requirements between a crank case and a foot pedal. Frankly it would not be unheard of to do some such parts on a well constructed router type machine. This would be a lot stiffer machine than what is required for wax. For the more critical parts you may find buying a good mill is the smart move.

[Brentoxicated]

Wizard, Basically i want to get as close as accurate as possible in wax and cast in aluminum, then on heavier mill- bore and fit bearings and studs, etc. so it will need to be accurate, akin to a Bridgeport mill or equivalent i would think.

RE: motor cycle parts: flathead motor case halves, heads, and if i can cast iron- cylinders and frame pieces,inner and outer primary covers, etc.