Xref: utzoo rec.org.sca:4650 trial.rec.metalworking:12 Path: utzoo!attcan!uunet!cme!durer!legowik From: legowik@cme.nist.gov (Steven Legowik) Newsgroups: rec.org.sca,trial.rec.metalworking Subject: Re: Blacksmithing Message-ID: Date: 27 Jul 90 13:13:29 GMT References: <26A74055.33FE@intercon.com> <1815@otc.otca.oz> Sender: news@cme.nist.gov Organization: National Institute of Standards and Technology Lines: 46 In-reply-to: wayner@otc.otca.oz's message of 23 Jul 90 23:02:07 GMT I haven't yet had the opportunity to experiment with a whole lot of different types of coals (or cokes). Amanda, you are the second person I have come across that swears by anthracite coal. I understand that it is a bit harder to get started than soft (bituminous) coal. The fellow I talked with before said that he had to start his anthracite fire using a wad of kerosine soaked rags, but once he had it going it would stay lit over night. So he didn't have to restart his fire all that often. I dont do blacksmithing full time so that probably wouldn't do me much good. Probably when I finish off my current supply of coal I will experiment with some of the other varieties available to see what I like. I still haven't used up the coal that I started with two years ago. I have been using crushed bituminous coal. Admittedly it does produce large clouds of dense dirty yellow smoke when the fire is first started, but once the coal has coked it burns pretty cleanly. Fortunatly I have been doing all of my smithing outside and that isn't too much of a problem. It may not be the greatest coal around, but I have been doing alright with it. The price was right. I aquired several hundred pounds, maybe even approaching a ton, of the coal from a blacksmith for free. He found some cleaner burning coal and stopped using his old coal. The economics of running a forge are a bit different when you are making a living at it, which I dont. I think a forging fire depends as much on the type of forge, and how you build your fire as it does on the fuel you use. The fellow that taught me to forge weld claimed that you could make a weld in just about any kind of coal, as long as you had a good air blast and a deep enough fire. Wayne, if you are having trouble getting a weld to take there is probably something wrong with the forge, the fire, or your technique, not the coal. You are fluxing the steel before trying to make the weld arn't you? As for carborizing the steel, that is just a natural result of working in a carbon fire. The heated metal will absorb the carbon by diffusion when heated up to forging temperatures. The longer the iron spend in the fire the more carbon it is going to absorb. This is the process by which steel was produce in the Middle Ages. I have had pieces of soft iron case harden in the forge to the point where I had great difficulties drilling holes through the piece. This affect is increased when the flow of air through the fire is reduced, a reducing fire. Of course if you have too much air the iron will oxidize too much. -steve