Strictly speaking, it's illegal to copy any patented (not "patton", he was a general, and not copyright, which applies to published materials) item, even for personal use. Realistically, if you make something for your personal use and you're not selling it or using it to make a profit (i.e. in a business), nobody, including the patent holder, is likely to care. But don't post your replication drawings online.
It's not a matter of whether it's "slightly different"; a utility patent (the most common kind) describes the function of the patented item. If your copy functions the same way, it infringes on the patent. You can't, for example, change the color or the shape of the handle (unless the handle shape is described in the patent and is critical to the function) and get around the patent.
Patents are useful but you need the money to back it up... in real terms, a patent simply gives you the right to sue somebody for using your invention, but that can be an expensive, drawn out process.