A really complete answer to your question really would require a book, and a large one at that! Not the least of your problems is that your chansaw bar may be crap for making a knife. What I am saying is, it's mystery steel - you don't know what it is. In a previous thread somewhere on these forums I remember reading that some chainsaw bars are high carbon, hardenable steel and some aren't. Unfortunately, there's no way to really know without trying to harden a piece of it. So, my first piece of advice would be to test a piece and see if it hardens if you insist on using it. A better choice, especially for a newbie, would be to buy a piece of good high carbon steel from any of the knife supply houses and eliminate all the guessing from your first knife. This would help insure that after you put all that work into making that first blade you will have a fair chance of actually making a usable knife. Most newbies assume they are saving big bucks by recycling a piece of scrap steel but in most cases it's a false economy. A good piece of steel like 1095, 1084 or 5160 can be purchased for less than $10. Even with shipping that's a bargain when you consider that you don't need to test it, it's already annealed when you get it, it's clean and flat to begin with, and you will know precisely how to heat treat it.
Whether or not a tutorial starts with a chainsaw bar doesn't matter. You already have your blade profiled. Now, grind your bevels and leave the blade a little over sized. If you use the chainsaw bar you should probably anneal it and then heat treat it. If you bought some steel, just heat treat it. There are tens, possibly hundreds of threads discussing how to heat treat carbon steel so look them up for any details you might want but here's the basics: There are also many, many threads discussing grinding techniques.
Heat the steel hot enough that a magnet won't stick to it and no more than that hot. Quench the hot blade in warm oil (hydraulic fluid, used motor oil, almost any oil). Temper the blade at 300F to 400F (somewhere in there, you don't know what the steel is so start at 300 and add 25 each time you do the temper cycle until you get what you want) for one hour, and do that two times. Test the blade with a file or do the brass rod test (Search for it) to see if the blade is about right. If not, add 25 F and temper again. Of course, if the blade was too soft when it came out of the quench or after the 300F temper then the steel wasn't any good to start with.
All of this assumes you have some way to heat the steel to non-magnetic. If you don't there are many ways you can approach that problem. Read about (Search) building a forge, using an acetylene torch to heat treat, or building a 'one-brick' forge to use with a propane torch. It doesn't have to be fancy or expensive to heat treat a carbon blade.
OK, that was the shotgun approach answer because we don't know what tools you have and there are a million (give or take) ways to make and heat treat a knife blade.
Think about that steel issue I mentioned, do some Searching, and when you're ready we'll try to answer any specific questions you may have.
I don't really know of any tutorial that would definitely help you but there are some tutorials in the Workshop section of the forum and also a few in the sticky notes at the top of this forum .....
Last edited by Ray Rogers; 05-21-2005 at 06:53 PM.
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