maddog

It means any combination of weights where the anvil mass is 25x the mass of the hammer. 50:2 also 25:1, 1000:40 etc. They will all have the same %loss.

Great deal! It does look like an HB. Check above the left front foot under the horn. If there is a single digit about 5/8" high stamped there, its almost surely an HB. Looks like the plate is sound, the edges are good and just a bit of swayback around the sweet spot in the center. Looks like there are a couple of cutting torch nicks in the edges which is not unsual. It looks great!

I was looking over the offerings on ebay for Wilton Vises. How does one know whether a model is cast iron or ductile steel

I think a degree in physics would be serious overkill as a background for practical smithing in a regular shop. But doing the basic college physics curriculum e.g working through Sears & Zemansky with emphasis on the sections about mechanics would be very useful. The math that goes with it wouldn't hurt either. Now if he wanted to work in a big industrial operation (I mean big industry not big forgings) then I expect some kind of engineering degree would be necessary.

Bob, thanks, I'm okay now. Deep breaths. Think happy happy place.... fciron, I thought your comment about user error was on the money. Another comment you made about the shape of the anvil is IMO very much to the point. The analysis above assumed an idealized simplified set up. The anvil is somehow magically suspended in the air and all its mass reacts simultaneously, sort of like hitting a solid cone of steel on its pointy end. There is no consideration of support or shape. I think in the case of power hammers, because of their design, this is reasonably close to what actually happens. With an anvil however you are essentially striking a fat bar in the middle. The center goes down, the ends fold up, the anvil vibrates and energy is wasted. Consider an extreme case in which a 400# "anvil" is shaped as long piece of 2" sq. Striking it in the center is not going to give you 400#'s worth of reaction. So the length of the anvil, the thickness of its waist and such are going to have a significant effect on its "effective mass". A Peter Wright should be more efficient when struck in the middle of its face than a Hay Budden of the same size. Similar considerations should apply to working on the horn or the tail. I don't have the knowledge to work out a quantitative analysis of this effect. Looking at beam deflections might give some insight. To really be able to compare a PW vs an HB pound for pound and dollar for dollar would require the use of a finite element program. Something MEs use all the time. A finite element mesh is really a kind of 3D spreadsheet The other significant issue is the base and how the anvil is mounted on it. It seems to me that some mounting schemes could increase the effective mass of the anvil and others have little effect.

So the buzz has gone and we are now talking reality? Let’s do some of that. The reality is that this thread is not about finances, mismanaged businesses or layoffs it’s about the anvil mass, why and how it might be important. But since it seems to have been hijacked by sour, mean spirited rants on the evils of thinking, I have a few things to say. Bajajoaquin and I both went to some effort to develop and present this material. It was done in the spirit of making a useful contribution to the discussion. A very interesting and useful discussion. To have this dismissed out of hand with the words “spread sheets be xxxxxx” is rude. Xxxx rude! And with what justification? That someone once misused this very fine tool? This is like saying “hammers be xxxxxx” because you once saw someone hit his thumb. Is that a realistic assessment of hammers? This followed by another post frankly gloating over the fact that someone had xxxxxx on the parade is unpleasant and nasty. Spreadsheets are wonderful tools. They are heavily used in engineering and science as well as business. A great many of the products you use and depend on were designed with them and are the better for it. If you don’t know how to use one or even what they can do, that’s your loss. Are you proposing that businesses don’t do any accounting and just keep their money in a shoebox? Or perhaps they should do their books with pencil and paper? All accounting software is essentially specialized spreadsheets. Should they not make plans or forecasts at all and just take it as it comes? Reality is that most products today are deeply engineered and that means serious mathematical modeling up front by the “knowers” who learned this stuff in school. In fact many of today’s products would simply not be possible with this kind of work. The very computers that people use to get online and rant about the evils of theory depend critically on just that - deep theory . Many deep theories. Among them Quantum Mechanics. (no that does not involve tiny wrenches). Modern engineering even more than science or perhaps any other discipline has produced a long series of fantastic accomplishments. To contemptuously dismiss the men who do this work is peevishness not realism. Practical experience only goes so far. When the US wanted to land a man on the moon, who had the necessary practical experience that could be consulted? How many times will your bridges have to fail or your aircraft fall out of the sky before you have the necessary experience to build one that works? The bizarre concoctions for welding and tempering that were part of the lore of blacksmithing were all fruits of practical experience. Practical experience can blind you to possibilities that seem to contradict it. It was practical experience that told us the Earth is stationary and that the sun rotates around it every day. After all, if the earth is spinning why don’t things fly off? It took a significant mathematical effort by men like Galileo and Copernicus to see things clearly. It was from this work that an understanding of gravity finally evolved. An effort that involved years and years of meticulous recording of astronomical observations and then scrutinizing them for deep patterns. Yes, spreadsheets and bean counting! Of course theory must be tempered with experience and of course it must be used wisely with some skepticism and a clear understanding of its limits. Of course there are idiots out there who misuse their tools and there are times when even the best design efforts go wrong. Practical experience and theory should work together. An industry where the trades and the engineers are at war with each other is essentially a circular firing squad. What else do you call it when a craftsman thinks it’s funny to hand an unsuspecting office worker a piece of iron at black heat and watch him burn? They should be trying to make each other look good, not bad. They should be helping each other to avoid pitfalls not leading them into traps. I am not surprised many of these industries fail. That’s a dose of reality. Reality is that without engineers and their theory to design our products we would be a third world country. Developing countries go to great lengths to train their engineers at first rate schools in the West. Successful industries compete for the best engineering graduates and at considerable cost. Why don’t at least some of them wise up , hire a bunch of “doers” in hard hats and save a bundle? Reality is that after several pages of discussion in this thread, much of it by people with a great deal of practical, professional experience using anvils and power hammers we hadn’t gotten to a close understanding of how things worked. We understood that that bigger the anvil the less it moved and that meant less work wasted. We realized there must be a point of diminishing returns but no one knew where that was. Grant pointed out that 100% efficiency was impossible since it required an infinitely massive anvil and also suggested that the relationship was quadratic. Which it is in a general sense. But no one could answer the simple question, “should I spend the extra money for a 400# anvil, or go the extra expense for the power hammer with a 2000# block?” until Bajajoaquin posted his spreadsheet. Not that his numbers are the last word but they are a big step forward. And how would you get this information otherwise? It wasn’t available as ready knowledge from those with the practical experience. Short of lining up a series of power hammers and anvils and having the same worker repeat the same tasks on each machine, how else? There seem to be quite a few power hammers out there with seriously mismatched hammers and anvils. Perhaps the fruits of seat of the pants engineering by people who don’t like spread sheets. I didn’t do the math. Newton did. I did some simple manipulations to specialize his equations to this question. I presented my results with some skepticism though I would bet fighting money that they give a useful insight into what is going on. I stated that I would have been more confident if they had come from a mechanical engineer who has practical experience in analyzing this kind of problem and applying the equations. Newtons equations have been around for 500 years and are well tested by practical experience. They give good results in non relativistic applications. The numbers that I got are consistent with industry practice. So how was this unrealistic? Why on earth shouldn’t we use this resource? Bajajoaquin when presenting his excellent spreadsheet, was very careful to list his working assumptions. How do you get more real than that? Mathematical models are very much like drawings. A drawing can give you a great deal of insight. It can show relationships clearly and even point out ones that you didn’t suspect existed. It allows you play "what if?". It has limits. A drawing is not the same as the real thing and if you forget that you will have problems but would you design anything more than a trivial project without some kind of drawing or at least a sketch? A mathematical model is more abstract and more versatile but more difficult to interpret, hence the need for things like spreadsheet presentations. When you multiply WxL to figure out how much carpet you need for your living room you are using a mathematical model for surface area. What happens in reality is never quite WxL. The walls aren’t quite straight, the floor is bumpy and even your ruler is not that accurate. But you get results that are close enough to be very useful. If you forget the limitations of this model and use WxL for a problem like covering thousands of acres of farmland with fertilizer you might be seriously off because the model doesn’t account for the curvature of the earth. Something you can ignore when carpeting your living room. The equations for elastic collisions are not very complicated, but even the most sophisticated mathematical models are just like this. They are simplifications and approximations that are extremely useful when used wisely.

Nah, you don't need to worry about how long it took. Even an experienced smith expects to improve his time considerably the first time he forges something new. In your case, you basic skills will be improving too. Make more tongs. You will improve rapidly and have lots of tongs. :)

I wish your mom good luck with this. Having a pet waiting for you at home can really boost your spirits.

I wish a mechanical engineer would say something on this topic. But in the meantime I opened my college physicis book and played around with the equations for elastic collisions. This assumes that the hammer just strikes the anvil face, without any deformation and rebounds. A real life forging blow is more complicated. For different ratios of anvil mass to hammer mass, I get these numbers for the percentage of energy lost to anvil movement. Ratio %Loss 5:1 55% 10:1 33% 15:1 23% 20:1 18% 25:1 15% The equation I used was %Energy loss = 4r /(1+r)^2 x 100 where r is the anvil to hammer mass ratio. These results should be treated with some skepticism. I am not an ME. The numbers do seem plausible. They say there is not much point in going beyond 20:1 which seems to be industry practice and it's hard to get more than 80% efficiency.

Those are pretty darn good for a first pair. A lot of first efforts are not really practical for various reasons, like a thin section near the jaws. Yours not only look nice but are sound too. If you can do that, you can make yourself all the tongs you need. I have a pair with jaws like that and find them very useful. Just a suggestion: You might draw out the straight jaw (dunno what to call it) to a short taper and curl it back on itself in a little scroll. Just for looks.

Yes there is a limit to the speed available. At some point increased speed comes at the cost of hammer control.

It's possible she was just looking for an example of what she has in mind rather than expecting you to produce Lowe's version at Lowe's price. I don't know how the conversation went, but it's easy to make the mistake of reacting to words that were never said and never intended.

I didn't mean to offend or hurt anyone. I am sincerely sorry if I did. This is a painful matter and I feel for Bentiron. I raised kids and I know the anguish involved. I had never heard that expression and just wanted to know what it meant. It occurred to me afterwards to google it. Perhaps it was insensitive to ask but I wasn't alert to it. I am not a native born American and sometimes the slang gets by me. Everyone gets to act like a jerk sometimes. Often without realizing what they have done. When that happens, it's usually enough to give a person a nudge in the right direction without having to imply that he does that all the time.

Nice! You can find a whole range of old vises using the same basic design as a leg vise, From large leg vises down to small handheld clamps 6" long. You can usually find a good selection on ebay. I think at one time that was the standard design pattern for vises. FWIW I have seen the size you have described as a jeweler's vise on ebay. I have a few of the hand clamps. I've been wanting one similar to yours for a while but couldn't justify the cost. I don't need it. Just want it :)

What does that expression mean?

I'm inclined to say that a ball pein doesnt have enough mass to make a decent flatter. I made a flatter by butt welding a square piece of leaf spring onto the end of a block of 1 1/4" mild steel. I tack welded the face in position with my arc welder, heated it up in the forge and hammered the weld. It went easy and has seen a fair amount of use.

Forge welding is done from light yellow to white hot. You don't say whether you are using coal or gas. The fire management is important and different with each. The borax goes on at about orange hot. The weld area should be clean but does not have to be free of scale. The mating surfaces should be convex. The pieces are welded with light taps not heavy blows. Larger stock is easier to weld than small stuff because it holds the heat longer. The weld you described, called a faggot weld, is an easy one to do but not a good one to start with because it's harder to know when the weld is sticking or just held in place by the bend. Try putting two pieces of, say 1/2" round side by side in the forge. Flux at orange. Heat to yellow/white and touch them together. When they are ready to weld you will feel them stick. Give them a another minute and push them up against each other, perhaps squeeze them together with tongs. If they hold, pull them out and see if you can complete the weld.

The plan sounds good. The price seems about right. The dent doesn't matter much but knocking it back out is a good idea. What are the dimensions of the tank? I like to put at least two inches of kaowool in the liner. What size burner are you going to use?

That's an interesting idea. My first thoughts are that having the head counterbalanced will rob the hammer of impact since its center of gravit will be behind the head. Also most of the handle flex will now be in the middle, where your hand is, rather than at the head. If I understand it, Hofi's technique is to use the rebound, together with a bit of arm motion to rotate the hammer to vertical before lifting from the shoulder. Amit Harlev says about this that getting the hammer to vertical is the hardest part of the stroke. So they seem to agree with you on the main issues in lifting the hammer for a strike. The blocky shape of the hofi hammer makes it easier to tilt since the mass is compact and also helps to keep the center of gravity above the face when using the edges to fuller.

Some more alternatives: Arc welding a shank on. Using mild steel when appropriate not only is it softer but it can be worked at welding heat. Doing the heavy reduction with a aggressive fuller or a pair of fullers in a spring too. Forging from leafspring with a flat shank that fits the hardy hole on the diamond. Making a removeable insert for the hardy to reduce it to 3/4" or even 5/8" so that the forgings are smaller. What's so bad about fishlips? I just let them form and then grind or cut off the end. I use a 5# hammer for the initial knockdown of heavy stock. I am very careful with my technique when I do. It's easy to damage one's arm. Also there are plans for a small home built rolling mill which is idea for drawing out. I don't know it's capacity though.

Well thats interesting info about the degradation to Boron Trioxide and the ph. I will have to see what happens in practice. I looked for roach powder in my town but couldn't find it so I bought from ebay. If the roaches ever show up in my house they will be xxxx sorry! I add brake drum chips to my borax and find it really helps. Just another recipe in the Black Art of Forge Welding.

10 mins to full welding heat! Looks like you are cooking with gas now! I confess I am a bit jealous of your hi temp pyrometer. I suggest you use it to train your eye to read the colors in your forge. I don't know about shipping to SA but needle valves are available on ebay for $20 or less. Needle valves on ebay Like you I dont use a nozzle when the burner is in the forge. I find they just corrode away. I shape the refractory to channel the gas. If you need to use the by itself, put the flare back on. In this setup the burner and the forge are all part of a single venturi system. The burner has to be tuned to the forge and that will depend on how you have it set up at any time. How is the front blocked off. What kind of work piece is in the forge etc. The relationship between the choke and the combustion mix is complicated. On mine it, at 20 psi I can set the choke down to 25%. At very low pressures when the air entrainment is not as strong, I need to open the choke to get a neutral burn. I just do it by experiment and experience. When you get the exhaust looking right for a neutral burn, do fine adjustments based on the amount of scale that gets formed on the work piece. Atmospherics often burn hottest running a bit lean. I like to set mine a bit lean and then kick up that gas a notch when the work goes in, to reduce scaling. To get a tangential alignment, your burner probably needs to point in horizonataly and perhaps slightly backwards. If you switch to a 3/4" you may have enough space to change the angle. Anyway this is a refinement. What you have now is working great. The forge shell will get hot enough to boil water. Some configurations will get hot around the burner entrance. This is more likely if you have a tangential entry. Make sure this is not due to combustion gas backing up through the burner port and flowing into the kaowool lining. Your lining will deteriorate fast if that happens. Seal the burner tube by packing it with kaowool. It is likely that the end of the tube will start to corrode. I just consider it a consumable and replace the nipple every so often. You can coat it with ITC 100 to slow down the process. The kaowool barrier in front is a good proof of principle but it wont last long. You need to decide on a configuration. A moveable door lined with refractory or a stack of soft firebrick or whatever. I like the firebrick because its versatile but the bricks fall apart. Any opening through which you can see directly into the forge chamber should be as kept as small as reasonably possible. Line of sight is a direct escape path for the radiation. I find it very useful to have a firebrick porch at the mouth of forge and place the reflecting barrier on that. This allows me to lay long pieces across the forge mouth without having to thread them through the chamber. I guess if you are just doing blades this doesnt matter. I find that with the right configuration I can even do welds at the mouth. I dont often put the work into the chamber.

Let's cut the XXXX. Bigger is better! Why? Because it's bigger and that's better! I have a 355# HB and I say all you guys with 354#'ers or lighter are a buncha girlie men. As for Stewart with his 700# beast I say, "do I really need an anvil that big?" ;)

"...Mr. Hung said his wife told him she never would have married him if she had known he would become a blacksmith. " It is sad. Bit if there is a market for blacksmith work, the craft will survive.

At forging temperature, the main factor in heat transfer is radiative. Meaning the forge sheds heat in the form of light at a tremendous rate. That big opening is draining a huge amount of heat from the little forge. You need to set up a barrier of fire brick, for instance, to reflect back the heat. It doesnt have to be air tight. You can set it an inch in front of the forge mouth. You can't stop the exhaust from escaping anyway and you don't want to choke an atmospheric burner. Here are some examples. . It should make a very big difference. If you have one, I think a 3/4" burner would be a better match. Though it looks like the 1"er is working okYou should get a smaller or no cold spot depending on the setting and you will be able to idle at a much lower setting. If you turn down that big burner too much, the flow in the tube will slow down to the point where it will burn back and start popping.