What are these CNC machines?

[golok]

I have heard many times about the CNC machine. To the best of my knowledge, it is used to cut by laser any metallic material in whatever shape that the computer programs it to do.

Is it specifically used for the making of knives?

Can someone give me a better explanation? If any company can buy a CNC machine, can they not make any knives of any shape and size?

 

[blgoode]

I use cnc machines to cut out dimensional letters for display work. Alot of shops use them to cut multiple patterns to speed up production. The one I use needs a vector format file to cut from. Not jpegs or photoshop or bitmaps. I trace those in illustrator then cut whatever I want. Hope this helps........

 

[rlinger]

CNC (computer numeric control). CNC is used in many manufacturing processes and the picture that comes to my mind whenever CNC is brought is an automated milling machine. They are controlled by a computer program and by no means limited to milling machines.

RL

 

[Matt Shade]

CNC, like those guys said is Computer Numeric Control. It has nothing to do with the type of cutter, it just means that a computer guides it. Its used for traditional equipment like lathes and mills as well as laser and water jet cutters.
The basic idea is that you map the part out in 3 dimensional coordinates (using a CAD program, computer aided drawing)and the machine can then read the map and guide the cutter to make the peice.

 

[toolie]

CNC's have come a Long way in the last few years. At present we can Machine 60-80 Cubic inches a Minute in Aluminum, 20-40 in steel, 10-15 in stainless. Its the cutting tool itself, as well as the advancements in raw number crunching that has brought this about.
In general the programmer takes the blueprint ( if a electronic file was not forwarded along with paperwork) and generates a graphic model of the part itself. the computer then translates this graphic model into mathmatical representations. Then the tool data must be input; size, how many cutting surfaces, cutting speeds and feeds, then this is translated into machine code that the CNC itself can understand. Then the proper tool order and the distances from the tool changer to the actual work piece must be set. A common location(reference point) is set BEFORE you begin this process somewhere on the part itself. ALL referenced are set from this location, and it can be moved ( floated) to any location at any time, after you load the original reference.
we have 5 axis machines, capable of machining all five sides in one set up. It still amazes me when we crank these machines up. The most powerfull has a 60 horsepower motor that will send a 6.0 diameter cutter across stainless steel 1/4 deep at a time. the chips coming off are red hot, as the heat and distortion are sent into the chips, and away from the tool and the material.

friggin wonderfull

 

[toolie]

the answer to cutting knives is yes, once you buy about a million dollars worth of CNC cutters, grinders, and support equipment you can make any knife imaginable within a few minutes out of any material you could desire.
Standard laser cutting is in 2 dimensions, so you need to then set up another machine to cut or grind the angles and bevels to the edge.
FUll blown CNC machining (3-5 axis)can machine to the edge itself, but you need specialized tooling for that as well.
You also must have quite a bit of experience with set ups, tooling systems, cutting technology, and stay up on latest technology. we attend about 100 hours of schooling per year. knives are a bit of work to set up, we always run extras for the next few orders so we dont need to reset machines next go around. these are for medical and food processing, paper cutting and related uses.