amanda@mermaid.intercon.com (Amanda Walker) (07/21/90)
[In which we discover yet another random skill out of my past...] In article <LEGOWIK.90Jul20100927@knight.cme.nist.gov>, legowik@cme.nist.gov (Steven Legowik) writes: > I personally prefer coal over charcoal. I think it last longer and > burns hotter. If you use coal, be sure to use nice, hard, anthracite coal. Soft high-sulfur coal generates extremely annoying and noxious fumes when it's initially ignited. My favorite fuel is coke: it's more expensive to buy, but it gives you a very clean, hot fire right from the start. Since a coal fire is at its best after it has turned into coke anyway, I figure why not start it out that way :-)? I've also seen forges fired with natural gas & propane, which mean fuel is cnveniently available, but you have to be *real* careful not to de-carburize your steel in them. They seem to be better for things like glassblowing than for blacksmithing. -- Amanda Walker <amanda@intercon.com> InterCon Systems Corporation
wayner@otc.otca.oz (Wayne Robinson) (07/24/90)
in article <26A74055.33FE@intercon.com>, amanda@mermaid.intercon.com (Amanda Walker) says: > Xref: otc rec.org.sca:529 trial.rec.metalworking:3 > > [In which we discover yet another random skill out of my past...] > > In article <LEGOWIK.90Jul20100927@knight.cme.nist.gov>, legowik@cme.nist.gov > (Steven Legowik) writes: >> I personally prefer coal over charcoal. I think it last longer and >> burns hotter. We use coke as we found that (Australian) Coal tends to carburise the steel excessively. I guess it's all right if you use mild steel, but most of the High carbon steels tend to go brittle. I have never been able to weld using coal either as I can't get the steel hot enough. Wayne.
legowik@cme.nist.gov (Steven Legowik) (07/27/90)
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
legowik@cme.nist.gov (Steven Legowik) (07/27/90)
In article <26A74055.33FE@intercon.com> amanda@mermaid.intercon.com (Amanda Walker) writes: > I've also seen forges fired with natural gas & propane, which mean fuel > is cnveniently available, but you have to be *real* careful not to > de-carburize your steel in them. They seem to be better for things like > glassblowing than for blacksmithing. I have seen gas & propane furnaces in production blacksmithing shops. I understand that they are very useful for heating large pieces of metal quickly and efficiently. The gas fired furnaces do not get hot enough to do welds so there is no need to worry about burning the metal by accident. I understand that the air-fuel mixture is very critical. However if you are working primarily in mild steel you wouldn't be all that worried about de-carburizing it. -steve
jerry@walt.cc.utexas.edu (Jerry Porter) (07/29/90)
legowik@cme.nist.gov (Steven Legowik) writes: > >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. I'm not sure what kind of coal I'm using but its fairly hard, and smokes yellow untill it gets going, but it cokes up nice. Makes very little smoke once it gets going. I'm thinking that it must by anthracite coal, but all I know is its sold as smithing coal. It gets plenty hot, i.e. I've burned steel more than once. >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 I've only found one place and that sells coal, and that was a general store that has pretty much anything you can think of. What kind of places sell coal and where do you find these places? Heck, I still can find an anvile( well I've found several that I can't afford). >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 Being outside helps a lot. I'm, just waiting for the nehibors to complain about the smoke. Still once the fire is usable for smithing it doesn't smoke much. >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? What do you use for flux? I'm trying to learn everything from books because I can't find a local smith to learn from. I have learn that its hard work. I've learned not to burn the steel, and how hot it has to get to work it. I've also done some heat treating(hardning and tempering). But I just can not get a weld. I'm using some borax I bought at the store for my flux, but it doesn't make much difference, any suggestions? >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. I've notice that steel just gets ruined when exposed to too much air, when it is hot. If it does not actually burn it rusts so fast that it becomes very diffcult to work with. I'm glad I've been able to contact some people doing smithing out there on the net, tho. This disscusion, and e-mail to others informed me about a number of things to change that have helped a lot.(trial.metalworking was also dead for about 2 months before I started this thread...) Anyone have address of places that sell smithing supplies and equipment? Catalogs, etc? I'm kinda operating in a vacume. I do know about the ABAMA(or whatever the initals are for the blacksmiths's group.), but I don't have the money and haven't taken the time to check into it. Jerry Porter AKA Bass Wastelan | Disclaimer, we don't need no stinkn' Star's End 512-255-1030 2400baud | disclaimers. jerry@ccwf.cc.utexas.edu | --------------------------------------| |---------------------------| I LIKE it. | | All roads lead to Trantor.|
wayner@otc.otca.oz (Wayne Robinson) (07/30/90)
in article <LEGOWIK.90Jul27091329@dewey.cme.nist.gov>, legowik@cme.nist.gov (Steven Legowik) says: > Xref: otc rec.org.sca:613 trial.rec.metalworking:5 > 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 > 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? I use borax, but I can only weld on a "new" fire. After a few hours I just can't get it to welding heat. At least I can't burn the steel:-). A blacksmith friend on mine has the same trouble with hip portable forge so it could be a design fault. What do you people use as flux? Wayne.
steve@oresoft.com (Steve Hampson) (07/31/90)
It is nice to find so many people on the net are actively involved in blacksmithing. On the problem of being unable to weld after some period of time: The problem is probably caused by a clinker blocking the airway. You should always clean out your fire just before attempting welding and after about every hour of welding. Problems with clinkers will vary with the quality of coal an design of the forge, but it is a common problem and not insurmountable. On the problem of being unable to drill steel after forging: Don't quench mild steel and try to drill it. You should at least air cool mild steel or better yet anneal it. Most of the holes you need in forge work can be punched instead of drilled. On the subject of gas forges: You *can* forge weld with most gas forges. The steel behaves a little differently, however. You will not get a sparking white heat, the highest temperature you will attain is slightly below that, but a good weld is possible. Several of my friends and I have built portable gas forges that are every bit as good a coal forge without all the dirt, dust and smoke. It is possible to construct your gas forge to allow 2 foot long heats -- try *that* with coal. The national blacksmith's organization is ABANA (Artist Blacksmith's Association of North America). I highly recommend membership to all of you. Please keep cross-posting to rec.org.sca . My news feed is filtering out all the "trial" groups. Perhaps it is time to drop "trial" from rec.metalworking? -- Steve Hampson : uunet - Oregon Software : tektronix \!oresoft.COM!steve Portland, Oregon : reed / steve@oresoft.COM (503) 245-2202 : sun!nosun -
daveu@sco.COM (Dave Uebele) (08/01/90)
In article <1823@otc.otca.oz> wayner@otc.otca.oz (Wayne Robinson) writes: > > I use borax, but I can only weld on a "new" fire. After a few hours >I just can't get it to welding heat. At least I can't burn the steel:-). >A blacksmith friend on mine has the same trouble with hip portable forge >so it could be a design fault. What do you people use as flux? > > Wayne. It is certain nice to know there are other blacksmiths out there. I personally prefer electric glue (arc welding) to forge welding, mostly since I've already invested considerable time getting the hang of it. I've played with forge welding once or twice without too much luck. One these days... Anyway, my friends who forge weld have made several comments about fluxes. You can use the borax you find in the store (used for laundry) but it has problems. It has too high a water content. It tends to "dance" around on your piece as the water boils of. Borax is one of those chemicals that can "store" water in its molecular structure. Try a welding or pottery supply place for fluxs that contain borax. These should just spread and coat the piece being fluxed. I've also heard you can use fine sand (melts to silica) or rice hull ash. A couple of things about fire tending. One reason you might be able to weld only on a "new" fire is if you are not cleaning out your clinkers. Most coal has some compounds that don't burn and then tend to collect in the bottom of your fire, restrict your air flow, and pull heat out of your fire. I dug a clinker out of my fire the other day that had formed a whole circle around the grate. I'm not if I could describe clinker finding in your fire over the net though, it has a different feel to it when you probe with your fire rake. Use a sharp point to on your rake or other fire to tool probe around. It has a glassy feel to it, usually pretty hard and sometimes a little sticky. Once you pull it out, it have kind of a bulbous look and once it cools, it is hard and brittle, lots of colors, browns, blacks, and reds. Coke is more "spongy" much lighter. After you dig out the clinkers, try to pack the coke back in, pack more coal around the edge and give it a medium to strong blast to help the fire get re-established. For ease of fire starting. I generally smother my fire with green coal at the end of the day and let it smolder awhile. The next morning, I have a nice pile of coke to start the new fire. I generally start a little fire with newspaper and kindling. Once that is going I add small pieces of coke and increase the blast. As that gets going, add bigger pieces of coke and start banking the edge of the fire with coal/water about the consistency of thick mud. You should have a nice fire going by then. -- Dave Uebele uunet!sco!daveu or daveu@sco.com
wayner@otc.otca.oz (Wayne Robinson) (08/02/90)
in article <7317@scolex.sco.COM>, daveu@sco.COM (Dave Uebele) says: > Xref: otc rec.org.sca:660 trial.rec.metalworking:10 > > > In article <1823@otc.otca.oz> wayner@otc.otca.oz (Wayne Robinson) writes: > chemicals that can "store" water in its molecular structure. Try a welding > or pottery supply place for fluxs that contain borax. These should > just spread and coat the piece being fluxed. I've also heard > you can use fine sand (melts to silica) or rice hull ash. > > A couple of things about fire tending. One reason you might be able > to weld only on a "new" fire is if you are not cleaning out your clinkers. > Most coal has some compounds that don't burn and then tend to collect > in the bottom of your fire, restrict your air flow, and pull heat out of > your fire. I dug a clinker out of my fire the other day that had Thanks for the advice, I have used this very packet of Borax to make a pattern welded sword on another forge. We only had one dodgy weld, on an edge, it being the last one we made. The problem may be clinker removal, but this builds up far more slowly when using high grade coke than with coal. I don't know any smith in Australia who uses coal, as the coke here is so good. Four of the forges I have used had old vacuum cleaners for the blast, one had a manual rotary blower- it produced the best blast of all. May be our problem is that the air flow is restricted as it is and doesn't take much slag to block it. Some serious redesign work is in order for the forge I am building at the moment. What sort of blower do you use, and what is the diameter of the blast pipe on your forges? Wayne
daveu@sco.COM (Dave Uebele) (08/03/90)
In article <1828@otc.otca.oz> wayner@otc.otca.oz (Wayne Robinson) writes: >in article <7317@scolex.sco.COM>, daveu@sco.COM (Dave Uebele) says: >> Xref: otc rec.org.sca:660 trial.rec.metalworking:10 >> In article <1823@otc.otca.oz> wayner@otc.otca.oz (Wayne Robinson) writes: > >May be our problem is that the air flow is restricted as it is and doesn't >take much slag to block it. Some serious redesign work is in order for >the forge I am building at the moment. > What sort of blower do you use, and what is the diameter of >the blast pipe on your forges? > Wayne The most common type of blower in use around here is a "Champion" hand crank blower. I know about 4-6 in use by various smiths. There are also some older "Buffalo" blowers in use. The Champion blower has several brass gears in a cast iron case, the fan shaft ends up below and 90 degrees skewed from the hand crant shaft. I've seen fan housings from 8 - 16 inches in diameter. The output hole on the fan is about 3.5 - 4 inches in diameter. I think the patent date is around 1902 on the case of the one I use. The Buffalo blower has several exposed gears and leather belts and is usually mounted underneath the forge. It usually has some sort of ratchet mechanism and flywheel operated by a handle you pump up and down. I'm not sure of the patent date, but I suspect they are an earlier design, I've seen them listed in the reproduction 1902 Sears Catalog. On the forge I have been using (and copying in design for my own forge), the blower is connected to the forge via a piece of 4 inch metal flexible duct that would normally be used for a clothes dryer vent. This attaches to the stem of a 4 inch diameter cast iron T connection attached to the bottom of the forge. One end of the T cross bar goes up to the grate, the other goes down and has a hinged cover for dumping the ash that falls through the grate. This may be be what you need, a way to dispose of ash that falls through your grate so it does not block your airflow. The grate is piece of .5 inch plate that fits loosely inside the the pipe. There are several slots cut in it with a cutting torch. It is mounted on a shaft so you can rotate it to break up small clinkers. On the forge I'm building, I plan to do away with the the flexible duct work and just have the stem of the rigid pipe T come out to a fitting where I can set the blower. Another thing that might help with welding is to produce a deep fire. This forge has a fire box that goes about 3 inches below the main pan. Most of your fire is in the smaller fire box (about 12 inches on a side). The top pan can be 2 feet square and or larger and have sides that come up another 3 inches. You can pile your fuel fairly high this way. Leave a notch cut out of the top sides on each side of your firebox so you can get longer pieces into the fire/firebox. If you are working mostly on swords, you could make a longer and narrower fire box and forge. I've also seen forges powered by electric fans, usually small squirrel cage fans. Some have a rheostat control and others have some kind of gate between the fan and the forge. The gate is usually sheet metal or light plate that slides in and out of a slot cut in the piping. Look into the gates used with sawdust removal systems used in woodworking. For any kind of electric fan, I would recommend a foot switch so that the fan turns off when you turn to the anvil. Saves fuel that way. If you use a rheostat, often you need to turn it all the way up to get the fan turning then adjust if to the blast you want. If you have a gate and a deadman switch then you can keep the same blast adjustment. Other ideas for forges I'm working on include using the squirrel fan from an old central heating furnace and rigging it up to a big forge dug into the ground for tempering anvils. I think the approach I want there is air volume without too much velocity. I am also thinking of making a set of leather double chamber bellows that I can attach to my forge when I want to go more "primitive" than a hand crank. I have plans for building the bellows, just need to get moving on it. Sorry about the length of this, hope at least some of it helps. -- Dave Uebele uunet!sco!daveu or daveu@sco.com
legowik@cme.nist.gov (Steven Legowik) (08/04/90)
In article <7340@scolex.sco.COM> daveu@sco.COM (Dave Uebele) writes: >On the forge I have been using (and copying in design for my own forge), >the blower is connected to the forge via a piece of 4 inch metal flexible >duct that would normally be used for a clothes dryer vent. This attaches >to the stem of a 4 inch diameter cast iron T connection attached to the >bottom of the forge. One end of the T cross bar goes up to the grate, > Dave has pretty much said it all. I have two Champeon had crank blowers. One is about 9" in diameter and connected to a little portable forge pot. The other is about 16" in diameter and I connected it to my home made forge pot using a flexable metal dryer hose. That fire pot was constructed out of a sheet steel T arangement bolted onto a truck brake drum, which was lined with mortar. No clinker breaker. I couldn't think of a convenient way of constructing it. I died on me a month ago, after a year of service. RIP :-) It died of terminal rust because it was out in the weather. Now it is time for me to build another one and try something new. I have a number of ideas but haven't decided which to try first. Has anyone out there had any experince using or making a side blast forge? I'm also considering a design I read about in The Anvil's Ring. Steven Legowik Frederick, MD legowik@cme.nist.gov
jerry@walt.cc.utexas.edu (Jerry Porter) (08/07/90)
In article <1823@otc.otca.oz> wayner@otc.otca.oz (Wayne Robinson) writes: >legowik@cme.nist.gov (Steven Legowik) says: >> Xref: otc rec.org.sca:613 trial.rec.metalworking:5 >> 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 >> 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? > > I use borax, but I can only weld on a "new" fire. After a few hours >I just can't get it to welding heat. At least I can't burn the steel:-). >A blacksmith friend on mine has the same trouble with hip portable forge >so it could be a design fault. What do you people use as flux? > > Wayne. Hm... It took a long time to learn how to weld in a forge. I first tried borax from the grocery store, but I couldn't get it to work. I bought some weld/brazing flux and eventually got it to work. The flux looked just like the borax I bought, so I think its pretty much the same stuff. The things I have found that are important are: fluxing, heating, hammering. I have been able to weld once the forge gets going, it takes about 30 minutes to get going good. I'm using smithing coal right now. Once it gets going, you carefully heat the metal, then you flux it, heat it to welding heat, just before it starts to burn, then put the too pieces together and give it one goo solid hit. You can feel the metal stick when it is ready to weld. You might check to make sure you are still getting pently of air and the impuraties in the coal aren't clogging up your forge. You also might be running out of fuel. I know it sounds silly, but I had that happen to me some, when I first started. Jerry Porter AKA Bass Wastelan | Disclaimer, we don't need no stinkn' Star's End 512-255-1030 2400baud | disclaimers. jerry@ccwf.cc.utexas.edu | --------------------------------------| |---------------------------| I LIKE it. | | All roads lead to Trantor.|