WHICH file for sharpening tools and crampons???

There are now at least three videos on youtube, that look good, about sharpening your tools.  (I think one is AMGA and one is Petzl.) HOWEVER, I can't find any advice anywhere on WHICH file to buy. There are actually FIVE choices you have to make to pick out a file (see below); do you know all five for the file I should get for my tools? 

Somewhere I think I read it should be a "bastard" or "mill bastard".  However, at Home Despot the Nicholson files are specified by

1. length - what is the smallest that would be OK in case I want to travel with it?
2. Form (I suppose flat)
3. File cut - here you get
     a. "teeth" in diagonal lines in the metal,
     b. in TWO sets of diagonal lines intersecting each other
     c. both 45rows of teeth,
     c. circular lines in the file.
4. coarseness of "finish"; I'm REALLY confused by this because...
5. there is also, separately, rapid or gradual metal removal (Maybe there is also medium...???)

So, any guidance would be appreciated!

Thanks,

-TPC

I use a normal 8" bastard file at home. 
https://www.homedepot.com/p/Nicholson-8-in-Bastard-Cut-Mill-File-21832/100118750

I keep a flat file for a chainsaw in my screw roll up for if I really smacked a rock and need to sharpen something now
https://www.homedepot.com/p/Power-Care-DGFF001PC2-Depth-Gauge-and-Flat-File-DGFF001PC2/203555732

Hope that helps. 

I like a 6" mill bastard. It fits nicely into my screw bag and the finer cut lets me get get real close to factory angles on my tools. I prefer single file lines at 45 but that's mostly b/c  its what I also use for ski tuning.

I just use some old file that I stole from an old job. Any file should do. 

I use https://www.amazon.com/gp/product/B004EBMXZG/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 really like the handle

You are seriously overthinking it.

In my (limited) experience you are basically just trying to get any burrs off the edge and even out the geometry so the tool/pons cut into the ice fairly smoothly. This can be done with any small flat file.

Anything can be as complicated as you want it to be. Lots of people have spent lifetimes trying to sort out alchemy, for example.

Or you could walk into a hardware store and ask for a bastard file, like you knew you needed before you made this post.

I like this question. This answer is for posterity.

Answers below pertain to mainstream ice/mixed picks (petzl, BD, grivel, etc), not comp picks (krukonogi, bergsport-steinle, etc.). Mainstream picks are made of softer steel, because it's less likely to snap in ice or when torquing in cracks, but this also probably means it's different to sharpen than the comp picks, so don't take my advice to apply to comp picks. This is based on my own experience with mainstream picks.

1) Length: I've often considered taking a hacksaw to a file to shorten it for a climb as a weight saving tactic, which should tell you all you need to know.  If that's not enough: I wouldn't be concerned about a file being too short. Lifespan is proportional to length though, so for at home filing too short may be counterproductive (you just move on down the file as you wear sections out). I use small files and I only make use of about half the file's surface on each stroke while sharpening.

2) Flat. Taking off the first tooth benefits from some kind of curvature, but all the curved files I've seen either have too small or too large a radius to fit between the tip and second tooth. I've mostly given up on toothwork as a result.

3) The diagonal cuts are fine. Cross hatch might be just as good. I don't know what a circular cut is. 

4) Fine is better than coarse. A coarse file does the work faster, but doesn't leave a clean finish. Haven't noticed a performance difference, but it looks ugly.

I don't understand (5)

If you want something light for field sharpening, this: https://www.acmetools.com/milwaukee-big-hawg-diamond-file-48-09-5055/045242089369.html works great, and can do titanium and hardened steel as well. They are kinda pricey and do wear out, so I’d still recommend a traditional file for reworking geometry.

“c. circular lines in the file.”

This is a rasp, not really a file. It is really aggressive and is meant for softer things like wood. Don’t use this, it’d be a miserable experience.

“1) Length: I've often considered taking a hacksaw to a file to shorten it”

No sarcasm intended but this is a bad idea. Hacksaws aren’t meant for steel as hard as files. You might get lucky and find a saw that’s slightly harder than the file, but it’s gonna be a b!+@h to cut and it’ll ruin the saw. More likely it’ll just ruin the saw and you won’t get anywhere. If you want to shorten a file either go after it with abrasives like a grinding cut off wheel or clamp it in a vice and break it with a hammer (wear safety glasses!)

Cross hatched files are more aggressive than regular (diagonal lines) files. Either will work but a regular file is a bit easier to control.

Just a normal flat fine (i.e not coarse) file from any hardware store. Works for touching up any pick irrespective of the hardness of the metal (I use this on my kruk picks just fine, no diamond file needed). For serious reshaping you want a dremel or belt sander. Takes way too long with a hand file and the results are worse. Just go easy and don’t get the metal too hot (should be able to handle it without gloves and not burn yourself)

For what it's worth, as a general rule it's wise to skip the Amazon/Temu brands with weird names and get something from the hardware store or Home Depot. You never know what the manufacturing standards are at those cheapo factories, I've learned that the hard way a few times too many. Will Gadd has a Youtube video (from his ice climbing series from a few years ago) about sharpening and he highly recommends getting something of decent quality. Like with anything, you get what you pay for.

Because I forget to pack them in the car for the weekend, I have a bunch of bastard files that I get at Walmarts and Home Depots not too far from ice climbing venues. I break some of them in half and bring the non-handle half in my pocket on multi-pitch when there might be rock to mash my pick on. Filing on-route without the non-handle file half while wearing gloves is not optimal, but neither is carrying a file with a handle. Someday maybe I'll learn not to mash my ice tools into rock.

Do what all the comp guys do and just get a dremel and a couple carbide bits. 

I have a selection of files that I used to use for sharpening my chain saw.  I probably use a small triangle file for screws and a flat file for my tools the most often.

Did play around with using a round chainsaw file to put a slight hook on the tips of my ice screws and they seemed to bite well but any rock contact and they folded right over.  Also good for taking burrs off teeth and keeping those sharp corners very radiused (don't want stress risers!).

For a razor-sharp edge, I'll sometimes use a stone (same as for a hatchet or axe used to chop wood).  

Guide to files and filing