Thread: Nicholson File
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Old 10-25-2018, 10:33 PM
jimmontg jimmontg is offline
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Join Date: Jan 2016
Location: Now live in Las Cruces NM.
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Not to contradict Doug

Now what he's talking about is to heat to fourteen hundred plus degrees. First the anneal and then the hardening cycle. That's a full heat treat. If you have that capability then go ahead, best way to do it, start from scratch.

Now I've tempered Nicholson files down and I did it at 2 hours at 425 degrees. They are about RC58/59 hard then, maybe a little less, but are easier to grind than a file that isn't tempered. If I want them a little harder I went with 400, but that was old 1960's early '70s Nicholsons. I still have three of those files. Actually some makers only cut out the profile of their knives and HT them and then grind the bevels, that's no different that grinding files. I may have done that if I had had a wet grinder, but I always ground 90+ percent of my bevels before HT, those hardened knives are tough to grind.

Now if you want to temper the file and grind it that is ok too if you do not have a method to do a full heat treat. The big thing to remember is that when grinding do not let the blade get hot. Keep a large container of water close and a towel to rub excess water off before you start grinding again if you're using A/O belts, but otherwise don't worry about a little water. Reason I say use a towel with A/O belts is I used to have a small 1x42 grinder and water would break down the bonding agent of cheaper belts and make mud. lol Also use new belts and when it starts to bog down change the belt, it makes the job a lot easier.

I have made some pretty decent knives from files and the very first knives I ever made were made from files. They were filet knives that really held an edge very well and were easy to sharpen while I filetted two tons of rock fish. I worked on a fishing boat in the '70s and most affordable knives went dull way too fast and that's why I made those knives.
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