computers 101 (cad/cam/cnc and other trashtalk)

If you listen to the hype, you'll be told that cycling salvation comes in a can of alphabet soup.   The acronyms fly thick and fast at trade shows and in the bike shops, but most of it needs a healthy dose of salt.   Here are a few buzzwords you should read right past when you get knee-deep in it.

• cnc machined -- Cnc stands for computer numerical control.   It just means that instead of some guy twiddling the handles of a mill or lathe, a computer twiddles the knobs.   The machines are much more expensive than old-fashioned machine tools, and are capable of some fancy stuff that is damned near impossible without the computer.   It also looks like the computer is doing all the work, and the operator just pushes a few buttons.  But CNC machines have a number of important limitations.   First of all, the cost savings many people (including us not too long ago) expect may not be realized.   No less an authority than Alex Pong (Mr. Magic Motorcycle, to you) has said that it takes a higher skill level to run a cnc machine than it takes to run a normal machine, and we agree with him.   But for the cycling enthusiast, the most important thing to keep in mind is that machining is not always the best way to make a part.  In a perfect world, damned near everything would be forged, because forging generally makes the strongest possible part.  A forged part will almost always be stronger and more fatigue resistant that a machined part of the same material, size and shape. 

  
  

• cad -- computer aided design.   The computer is a wonderful tool for making pretty drawings and drawing complex shapes. Mr. Bebop would be lost without it.   But cad is subject to the most important computer acronym --GIGO.   A bad design can be perfectly executed with a cad system, so remember, garbage in, garbage out.

  
  

• cam -- computer aided manufacturing.  This is usually just another term for cnc, although nowadays it can apply to many processes other than machining.   In general, you just shouldn't care.