I have been slowly collecting tools for working on my own guns and want to add some needle files to my tool collection. And would appreciate some help picking 3 or 4 of the most useful shapes and cuts to get started. Thanks, Steve

I find my 3 square files get the most use by far, mostly when I'm working on checkering. Next would be my collection of various pillar files. However I also regularly use warding, hand, crossing & square and a couple parallel round files (think chainsaw files only smaller). I use a 2 cut for the vast majority of my work. I like to go slow & careful when removing metal since it cant be put back. I find a 2 cut works very well as far as speed of removal and leaves a pretty nice finish which requires very minimal touch-up if at all. However I have in my toolbox a couple 0 and 1 cut pillars and three squares up to 6 cut for very fine work. I also find three square rifflers are very handy.

Whatever you do, dont buy your files from the local hardware store. I recommend you buy top quality swiss files. Look for names like Grobet & Vallorbe, swiss pattern Nicholson are ok too.

For starters, I'd go with a Grobet needle file set in 2 cut plus a couple 6 or 8 inch pillar files in 2 cut

A while back in one of my projects I posted all the tools I use to complete the job. It's post 125 in this thread if you care to have a look.We're way beyond Dremel now, Melted & Melonited 4516-1

Cheers
Bill

Here's good simple reference for file shapes.
http://www.contenti.com/resources/library/files.pdf

Note the thickness & width of each. They differ between being tapered & parallel..
A quick file type reference also given. The names of them are often used loosely between the special types when talked about,,but there are very specific traits to some.
A file cut chart in the upper corner. Note that they change a bit for the different types of files.

With needle files, I'd have to say the 3-square, equaling, a half-round and a barrette would be the ones I use the most.
But everything shown, except the knife file, is of use in gun work. That exclusion is just from my own personal experience. Others may find it perfectly useful for a number of things.

The barrette is especially handy for tiny adjustments in tight places, trimming up the sides of a screw slot after repairing a damaged one, ect. They are very slim and very fragile because of it.
I have a couple barrette needle files that I thinned down even more to get what I wanted. They're still in one piece.
Needle files aren't to be expected to do heavy labor anyway. You'll break a few along the way.
If you're like me, you'll keep the pieces and end up making some other tool out of them.

If you do enough work you'll have a drawer full of the things of all different shapes and cuts. Remember the rougher cuts do dull with use . They're still usefull though, they just cut slower & finer that's all.

A #2 is a good all around cut. The really fine cut files don't get that much use IMHO. A rougher cut than that will give you a tough time on thin edged work, like a hacksaw blade that's too course for the work. But they do remove metal quite quickly dispite their size.

Many files I've altered to different shapes or to put safe edges on them for special purposes like opening up or changing the shape of a rear sight slot. No harm in that, just go slow when grinding as they heat up almost instantly because of their small size. You can re-harden them but it's easier not to have to!
You will have to heat & reharden if you decide you need a bent file for a project and want to make one instead of buying one. Not hard to do. No tempering is necessary but for the handle area if you happen to get that area too hard also.
A lot of people use them to touch up checkering. I use checkering tools for that and save the needle file for metal work.
Whatever works best for you..