The patent thing has been covered here before. A lot of knifemakers are afraid to cross the patent line even for one for themselves. While they should be concerned about litigation if they are selling their knives, personal use is another issue all together. Manufacture for personal use or say one for a gift is a gray area. What is not gray is the cost of litigation and recovery.
The patent holder can sue for damages and if the infringement is malicious, punitive damages.
Damages would be limited to the amount of money lost because of the infringement. No way will they recover attorneys fees unless the court awards the usual 30% of the damages. Let's say you copied a Spyderco that cost $30.00. Their award would be $30.00 plus a possible $10.00 for attorneys fees. The court may injoin you from further infringement.
Now the minimum cost to the company for this type of suit is in the neighborhood of $5,000.00. How much danger do you think you are in?
Don't get me wrong, I'm not in favor of running roughshod over the patent holders rights. I'm just saying that I want a hole in my knife just like Spyderco's, I'll put one there and not lose one minutes sleep!