Filing down a choil affecting the heat treatment?

[Carbon-]

So I've been toying with the idea of widening the choil on my ESEE 4 as shown in this thread but I wanted to ask about how that might affect the heat treatment. I'm still learning about knives and my understanding is that filing away metal (whether through a file or an automated sharpener) can sometimes cause issues with the heat treatment if the metal gets too hot. Is this something I'd need to worry about if I file down the choil by hand? Also, does anyone have any recommendations for files that might be suitable for this? I'm not particularly handy and would need to pick one up. Thanks.

Also, if what would be the best way to remove an inch of the coating on top of the spine? I'd like it to strike a ferro rod but need to remove the coating first.

 

[killgar]

Filing by hand- no, you don't have to worry at all about affecting the heat treat. You're not going to generate enough heat filing by hand. At least not if you take periodic breaks. It looks like the person in that thread had a good method (and inexpensive as well).

I've used a Dremel and grinding attachments to create choils without affecting the heat treat. The key with a Dremel is to grind just a little at a time, so little that there isn't time for any serious heat to build up, and take little breaks in between each grind to give time for cooling.

As far as removing the coating, that might depend on what type of coating it is. Fine grit sandpaper (200-400 grit) works well for removing many types of coatings.

I used a Dremel to create the sharpening choil on this knife using the method I described.

 

[TravisH]

I widened a choil on a spindle sander with a 1" drum.

The steel would have to get over 300°F before affecting the heat treat.

If using a power tool, touch the blade after several passes. If hot to the touch, dip it in cold water for 10~15 seconds.

 

[bodog]

I just did this because I thought the handle was really uncomfortable and too short:

it'll take you a little while hand filing it. With a cheap belt sander it took me about 30 minutes. I let the blade sit in a big cup of heavily iced water. Get the blade as cold as you can. Then take a couple of quick passes and then dunk the knife again for 30 seconds to a minute. A couple more passes, then dunk again for 30 seconds. Don't let the blade get warm to begin with and you won't need to worry about the hardness changing.

To answer your specific question, I don't think hand filing would make it hot enough but then again I don't think you'll be able to remove enough steel with the file to make a big difference either.

By the way, I did that with a $34 1" x 30" belt sander from harbor freight.