Buzzkill

Looks better than my home built 2x72 by a decent margin. The only question I have is regarding putting it on wheels. Even with locking casters you can sometimes get a little movement. Has that been any problem for you when you lean into it? I lied. I have a second question. Have you used it long enough to determine if 1.5 hp is enough? I used 1hp on mine and 4 step pulleys like you have but I can stall it pretty easily in the fastest arrangement so I'm thinking of bumping up to 2 hp.

I did a very small amount of leather work as a kid, but I think my sister was keeping Tandy in business for a while. I may see if she's interested in getting back into hand-tooled leather. Thanks for the ideas though. Right now it's more of a matter of time than anything else. Whenever I start to work on something it seems that someone I know can sense it and interrupt me about the time the forge is up to temp or I just about have my grinds right. I'm sure that doesn't happen to anyone else.

The handle is California buckeye burl that has been dyed and stabilized. After shaping I hand sanded it to 1000 grit. My wife tends to pick out the handle materials once we get the details. In this case the requested colors were green and gold. I haven't started making sheaths yet. When I do I'll probably start with Kydex, but it doesn't seem like a good home for that blade imo.

I managed to get this in the mail just in time for it to arrive at its destination on Christmas Eve day. It was supposed to be a Christmas gift for a 12 year old from his grandfather, but once it arrived grandpa decided to keep it and pass it down to him eventually. This is my 5th completed knife, but there were a few KSO predecessors and I have half a dozen or so blades that need to be finished out. I get more satisfaction out of designing and forging the blades than I do out of adding the furniture and finishing touches. I think my wife may have some WIP pics if she didn't lose them when she switched phones. If so I'll try to add those later.

Another note - the "O" in O1 stands for oil quenching. You are asking for trouble by quenching it in water. I'm surprised you just had one of them get a crack. I've had some O1 even air harden a bit when making a knife from it. Found it out the hard way when I tried to drill holes in the tang. Also, O1 is supposed to soak for about 10 to 20 minutes before quenching. It takes me a while to play with the propane pressure, air, and a magnet to get a stable temperature for the soak. You can get hard steel without the soak, but if you're trying to get the most out of it.........

Basically what I do is set the bar stock on edge on the anvil with the end that needs to be shaped away from me and then hammer the top corner back towards myself. I'm not a big fan of tongs when I make knives, so I usually weld a section of rebar or round stock to hold on to. This technique does take a little while to do since a lot of the force ends up going into your "tong hand" instead of down into the anvil, but it does get rid of the fishmouth effect with practice. You can use the horn on the anvil for some of this too as the curved shape allows you to hit into the steel with something solid behind it a little bit. As a side note if you start with round stock (like drill rod) that has been hot cut this isn't much of an issue since the shape naturally formed by the hot cut mostly keeps the fishmouth effect from ever occurring.

First, I'd shut the valves at the compressor at least one night and see if it still happens. If not, then the leak is in the air line. If it does then you know the leak is at the compressor, tank, or in the line up to the valve (assuming the valve doesn't leak). Make sure you check the drain line and fittings on the tank too. Once you determine which side of the valve is leaking at least you can eliminate a good portion of the system to check out more thoroughly. If it's leaking enough to kick on multiple times during the night I'm really surprised that using soapy water didn't reveal any leaks.

There's nothing to laugh about regarding that knife. If that were my first knife I'd be quite proud of it. How is the handle held in place? Just epoxy or do you have some other fasteners that we can't see in the pictures. With what you have there it is still entirely possible to bring the handle into a shape more to your liking. The 2 dimensional profile isn't bad, but you could sand it more to rounded shapes that feel good in the hand. That's always the key (for me anyway) with a knife handle. No matter how good or bad it looks if you're going to use it then you want it to feel comfortable in your hand while you are using it. If it's just going to hang on a wall then how it looks is more important. Regarding the swollen hands I can't say for sure what the reason is, but some people tend to grip the hammer handles far too tightly when they are starting out and that will result in a host of problems over time. As Daswulf suggested, you may want to look up some of the threads regarding anvil height, hammer control, etc. to see if you can pinpoint one or more issues. If you do have any bad habits, you want to change them early on before you get set in your ways as that will save you a lot of pain in the long run. I'm still a newbie at a lot of this stuff myself, but there's my 2 cents and hopefully some more experienced folks will chime in with some good advice.

Well there's a new bug I haven't seen before. I came back to read this thread and it reposted what I had written more than an hour ago. I swear there is a poltergeist in this software.

Brace yourself. That last question may get you an avalanche of answers like, "What will the knife be used for? Is it going to be a slicer, chopper, skinner?" The answer may be different depending on the application. It will narrow down the selection somewhat if you ask which is the easiest high carbon steel to *forge and home heat treat* but even then you will probably get some differing opinions.

Thanks for chiming in Mikey. I get what you're saying about moving on once you've determined a fact to be true. I've found that if I want to start tinkering with something it's better for me to know the "how" and "why" to avoid spending a lot of time messing around with something that was flawed in concept to begin with. There's nothing I hate more than spending a bunch of time on a failed project only to discover if I had asked the right questions before I started I could have gone in a different direction. They are still learning experiences of course, but frustrating ones.

I think I'm about done beating this dead horse on here, but I'll give it one more shot to see if I understand it correctly. The combustion of both propane and methane are net exothermic reactions including the formation of water vapor. So, if I understand what you are saying, after it forms the water vapor then absorbs more heat than was given off when it was created and whisks it out of the forge, thereby reducing the flame and forge temperature. This would also happen with propane, but to a lesser degree due to the lower ratio of water molecules formed when burning propane compared to methane. Is that what you've been telling me?

I have been very patient on here. I've asked a *very specific* question which I have yet to get an answer to. I have repeatedly stated that I'm not questioning the conclusion, but I want to know the how and the why of the phenomenon. I'm not after an argument. I'm interested in learning something I don't know. The way to do that is ask questions and research, both of which I have done without a good explanation being presented in either case. All I have gotten is essentially, "just accept that this is the way it is." I did that long ago. I have only asked for an explanation of *why* it is that way it is from the beginning. Neither you nor anyone else has provided anything resembling an answer to that question. So you are right. Enough! If you don't know then you are in the same boat as I am. If you do know and can enlighten me I'm more than happy to read the explanation. Just in case it wasn't clear before the question is still this: "Why is the formation of water vapor more of an issue when burning methane in a naturally aspirated burner than it is when burning propane in the same setup?"

Charlotte, I appreciate that it's not super simple, but I don't think digging out my old organic and p-chem books is going to explain why there would be a significant difference in the effect of water vapor produced by methane compared to water vapor produced by propane using a NA burner in a forge. That's a very specific set of circumstances. All of the other things you mention should be present regardless of which of those 2 fuels is burned. There is water vapor produced by burning both. There is heat produced by burning both. There is carbon dioxide (possibly some carbon monoxide) produced by both. There is red hot or hotter iron present in both. There is nitrogen present in both. There is no carbon-carbon bond to break in methane. That could account for some of the reduced heat production, but it still doesn't answer the question of the more significant role of water vapor when burning methane compared to propane. All the other variables are the same. The only difference is the starting fuel. Both of the fuels we are discussing are in the same family. I understand that at the atomic and molecular levels it's a many step process to go from the starting fuel to the exhaust gases rather than just a simple combination immediately producing the end products, but again it's the same for both of those fuels with the exception of the carbon-carbon bond that is present in propane and not in methane. Why does the water vapor produced by burning methane cool the flame and/or the forge more than the water vapor produced by burning propane if both are using naturally aspirated burners? That's what I'm trying to understand here. I'm not saying it doesn't happen. Water vapor is water vapor no matter where it came from, just as CO2 is CO2 regardless of the source. Doesn't matter if it's a human exhaling or a vehicle burning gasoline, carbon dioxide has certain properties and behaviors regardless of its origin. If water vapor absorbs a certain amount of heat per molecule, it will do that whether derived from methane or propane. Since there is nothing different about the substance itself then what causes the difference? Is it quantity? Is it location?

Frosty, As I said before, I'm not challenging the information that Mikey provided as far as his conclusion goes. I have done several searches and have not seen anything conclusive on a couple issues: 1) The cooling effect of water vapor formation with methane compared to propane in NA burners, and 2) Reasons why a NA burner using "high pressure" methane cannot reach forging temperatures. Since both propane and methane produce water vapor when burned I'm curious as to why the combustion of methane is more susceptible to any issues with water vapor than propane. A blown low pressure methane burner can achieve forging temps, so is this just a case of burning more fuel in a shorter time to hit those temps or is there some other reason. Mikey seems to have a handle on these issues, and so far I haven't found a better source to explain these things in terms I can understand.

I'm still having trouble with the idea that water vapor is a major player here. The oxidation of hydrogen to produce H2O gives off more heat than it absorbs or hydrogen wouldn't work as a fuel. When water vapor condenses to a liquid it also gives off heat. What I'm trying to wrap my head around is the role that the water vapor plays in the decreased heat output. You mentioned before that only about 20% of methane is consumed in the primary flame, with most of the remaining 80% being consumed in the secondary flame. What occurred to me is that perhaps a comparison would be along the lines of using a hundred butane cigarette lighters compared to one torch using the same amount of the same fuel. The same total heat output is obtained (assuming complete combustion of all fuel in both cases), but the lighters won't reach anywhere near the high temperature of the torch. Either way it seems that low pressure natural gas in a blown burner is suitable for producing temperatures needed for forging, glass blowing, etc. Is there something significantly different about the combustion between a NA burner and a blown burner using methane or is it simply a matter of burning more fuel in the same amount of time with forced air than you can with a NA burner?

My response disappeared too. Please understand that I'm not doubting your research or experience. I have very little and you've written at least one book, so I value the information you give far more than my recollection from chemistry classes a couple decades ago. I do like to understand how and why things are the way they are though, which is why I'm pursuing this.

Right, but both the CO2 and H2O reactions are exothermic, so heat is added in both cases. Methane has only slightly less theoretical heat than propane in complete combustion. What I'm curious about is why methane in a NA burner would end up with significantly less heat than propane if both were run at reasonably high pressures. Since methane requires less oxygen it would seem that the orifice size of the jet/mig tip would be larger than the corresponding propane setup and get a good mix of fuel and air. How does this result in more heat blowing out of the forge than happens with propane? I'm still not seeing why the water vapor would be more of an issue with methane than propane either. I'm not disputing that it is correct; I just don't understand *why* it is correct.

Mikey, Could you elaborate a bit? My chemistry is a little rusty, but to the best of my recollection, *any* hydrocarbon fuel will produce water vapor and CO2 as the two main exhaust gases. Doesn't matter if it's wood, coal, gasoline, propane, methane, etc. In fact that's why you can see water dripping from tailpipes on cold days before the entire exhaust system heats up. The water vapor is already hot when it's formed. If it condenses it gives off heat (that's why you can use pressurized steam to reach temperatures over 400 degrees F if you remove the condensate before equilibrium is reached). So, I'm confused as to why the water vapor from burning methane would affect flame or forge temperature more than another hydrocarbon fuel such as propane. Methane (CH4) should give off 2 water molecules and one CO2 molecule when combined with two diatomic molecules of oxygen. Propane (C3H8) would give off 4 water molecules and 3 CO2 molecules when combining with 5 molecules of diatomic oxygen. Granted, the heat given off by the oxidation of the two fuels isn't identical per molecule, but I don't get why there should be such a significant difference between the two pressurized gases in NA burners as long as the design allowed for proper fuel to air ratio and proper mixing in the burner tube.

For many of your questions there is no specific answer. A LOT depends on what you want to do and the shape and size of stock you plan to work. My first gas forge was way bigger than it needed to be. What I'm using currently is a disposable helium tank you can get at party supply stores for blowing up party balloons. I used 2 one inch layers of Superwool, which gives me an inside diameter of approximately 5 inches and it's about 11 inches long. Using a single 3/4 inch T burner of Frosty's design I can get the entire chamber to yellow-white heat in just a few minutes. However, I do think that for some things I do it would be better to have 2 one half inch burners instead. The pass through door - definitely. I can't imagine trying to work without one and unless you build a behemoth of a forge you will want one too. I welded a hinge and thin steel flap to cover the pass through when I'm not using it. You lose some heat through the opening, but it's well worth the trade-off in my opinion. I've tried a couple different entry angles for the burners, but all I can tell you is that for some things I prefer no direct contact with the flame and a more even heating in the chamber, and for other things I really like a "hot spot" to concentrate the highest heat in a small area on the metal. I haven't worked with a ribbon burner yet, but it's on my list of things to build and try out when I get the time. The chamber shape and size is really smith dependent and probably not even you knows what you'll end up wanting yet. My advice is build something fairly small to start with and recognize that within a couple months of using it you'll probably already have a list of design changes that you want to put into your next build. I can just about guarantee you that if you build one and you get the banging on hot metal addiction, you will build several forges within a few years. As for the heat to the outside of the shell - obviously around the openings it gets very hot. For the main part of the body mine is too hot to touch after a few minutes, but not hot enough to burn the original paint off even after several hours of use.

Thanks all. Frosty, that name is a holdover from my online gaming days more than 20 years ago (back when you had to "lag shoot" if anyone remembers that). I guess I just got used to using it everywhere online and never really thought about the implications. Anyway, he loved the knife and doesn't know me as "Uncle Buzzkill," so it's all good. I'm guessing your nieces know the score whether you show them the post or not.

Leaf spring steel. Dyed and stabilized maple burl handle. Brass pins. His favorite colors are green and gold so I thought this was a good match for him.

My "broken waist" HB had bolts through 2 holes a couple inches up from the broken point when I got it. Unfortunately someone had also welded angle steel to the bolts and to the anvil itself. I don't know for sure how much this compromised the anvil if at all, but I really wish that had not been done. When I made a flatter in the hardy hole the "ring" didn't sound right to me - almost like 2 pieces of steel touching each other rather than one solid piece. Again I don't know if that had anything to do with the welding or not, but I'd avoid welding on the anvil at all unless you really know your stuff there and even then if you have another option I'd try it first. If you try things that you know won't damage the anvil first, you can always move on to other things later.

Another option would be to use plates of steel (3/8 inch or thicker) on both sides in such a way that they clamp it in place. If the broken part of the waist was resting on a solid wooden block that is just a hair narrower than the waist, you could run bolts all the way through the wooden block and the 2 steel plates. Then just tighten those bolts up good and solid. After that your block could be mounted to nearly anything. You'd need to run the plates a fair way up the sides of the anvil and make sure they are *really* tight so that the anvil can't rock loose while in use. If the plates were long enough you could run extra bolts through under the horn and heel near the waist for extra clamping power and stability too.

Isn't it funny how a lot of those memories involve some combination of fire, explosives, and projectiles? Sometimes when I look back it's hard to believe I'm still alive. When you have curiosity, imagination, time, and access to tools, information, and certain substances there's no limit to the interesting and dangerous situations you can put yourself in.