Thanks a lot Trev I appreciate this information. You have given me the proper course of action. I remember seeing a small curved triangle file at princess auto as well now that you mention it. That might be the ticket. It is curved at the tip.
Yeah, skip the riffler files, or, at least, don't spend a bunch on a bunch of them, and buy a couple each of the singles of three and four square files. While the rifflers are nice in the odd occasion that you actually need to get in to a tight corner, down at the bottom of a cut-out, they are pretty much done once used, and you cannot do much more with one. The three square and four square jewelers files on the other hand, can be snapped off, to get a fresh bit of edge, they can also be heated and bent, then hardened again, if you need to make a riffler file out of one. Buy the cheapest ones you can, this is not a place to be spending anywhere up to $20 each for Swiss made top quality files.
Keep in mind that you are, generally, working around the outside of a curved surface, while a riffler file is really for working around an inside curved surface or for reaching in to odd nooks and crannies to break a sharp edge or deburr a part.
The long straight section of a file will work to help fix a line that is beginning to go crooked, which is another reason to avoid trying to get the whole line done in one pass. And lines WILL go crooked, as the cutter follows the grain instead of the checkering pattern.
There is room for LOTS of different tools, I would suggest not trying to cover your needs with an all in one kit simply because you are like to end up with a bunch of stuff that you won't ever use, in the way of line spacing cutters that are too fine or coarse, as well as multi line cutters (same reason) and border tools etc., that you may not ever use.
Just sayin'.
Cheers
Trev