Well, unfortunately the answer isn't 100% clear-cut, but in my opinion, a custom knife is a knife which is made especially for a single user. The knife will be made to fit the customer's hand well, it will be balanced according to that customer's wished, it will have a blade shape that the customer chose, whatever grind they want, the dimensions will be chosen, etc etc.
In short, a custom made knife is like a custom made suit...it is made to fit the customer and it is produced from whatever materials that customer chooses. Here's how I draw the line, at least. For examples from my own collection, I can say I have three true custom knives, all made by the late Madpoet. I have four of his knives, though. One is a drop point hunter that many would consider custom because Mel made eAch knife freehand, so all were a little different. I don't consider it a custom knife, though, because he didn't make it with a specific person in mind. The other three, though, were all made for me based on drawings I sent to Mel. The differences are subtle, but that's my opnion of what a custom knife is: a one-of-a-kind knife made to the customer's specs or based on what the custom will be using it for. It is a made-to-order knife. Oh, and as far as actual differences between customs and production knives? I would say that a well-made custom knife will always be better than a well-made
------------------production knife because it, in theory, is the perfect knife for the user in the application they are using it. I'm sure that there have been poorly-made customs, though, that are not as good as an off-the-shelf piece. It all depends on the maker.
My Custom Kydex Sheath page:
http://www.geocities.com/CollegePark/Lab/1298/knifehome.html
Palmer College of Chiropractic
On Two Wheels
agocs_s@dd.palmer.edu
Madpoet (Mel Sorg, Jr.) Tribute page:
http://www.geocities.com/CollegePark/Lab/1298/madpoet/main.html
[This message has been edited by Chiro75 (edited 17 October 1999).]