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15 hours ago, ThomasPowers said:

someone who knows how show you and work you through a couple of welds

Cool might actually buy the book Thomas. True it would be a real good idea alright with having someone show us how it is done. Had a wild goose chase now today with the blacksmith, the place I was told about was a motorbike repair shop. Don't ask. But anyways I did find that failing having someone show you as an alternative, maybe watching 20 YouTube videos by blacksmiths showing how it is done and watch for the similarities. At least that is the only option unless you are lucky to someone show it to you.  

Just to see if I got at least some of it worked out. The fire needs to be very hot, but not so hot as to melt or burn the steel one would be using. Air flow quantity is how that is controlled. It looks like the temperature is right just as the sparks are starting to fly. With my fire burning wood it would not get that hot. But noticed I do need the clay bricks of my forge to be glowing to get white heat. Hammer blows need to be very light for the first weld, tapping the mid line and then the edges and repeated the same on the other side of the weld. Reflux and get it back in to the fire fast. Next weld needs to be slightly harder and the third weld needs to be hammered hard enough to merge the steels together. Each time flux is applied by most. But then I have seen people do it all in one weld too. Maybe they edited it all out. As for burning of the flux no idea,. Difficult alloys one would need to know what steel you have, all I know is that welding high carbon steels to themselves is difficult. Also and because you and Charles told me - that certain fluxes do not work on newer steels, as the melting temperature of the flux needs to be lower because the alloys in them oxidize at lower temperatures. If you take to long from fire to hammer your steel will change color from white heat to orange and at that heat it is to late. The color may change depending on if it is day time or night time. Sure is not easy, but eventually we will get there.  

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Remember, the higher the carbon content the lower the welding temp. A thoraly heated billet is more important, so slowly roast the stock, don't sear it. I don't know if you roast marshmelows in India, but think that or cheese. 

Sparcks flying is bad for carbon steel, you are burning the carbon! Befor the sparks fly! A lot of miss information is based on wraught iron, rought acualy included silica Slag and was welded very hot. Modern steel, even 1018 will not tolerate that. 

I wouldn't describe the first strikes as light. I would call them firm, not so hard that the hammer bounces back off the anvil but hard enugh to drive any imperfections in fit together. Repeat at least 3 times 

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Forges burning charcoal not wood have been used to forge patternwelded swords for over a thousand years.  If yours will not weld it's an issue with the set up and user not the fuel.  Many people base their wood burning forges on the Whitlox on which I think is not a good design whatsoever---I wonder who the "professionals" that use it are?

The one CRS recently posted a picture of is a much better design and swapping out the bellows for a blower would make it easier to use.

Some alloys don't like to weld to themselves other even high C allows weld to themselves just fine---think of cable; it's all the same alloy generally.  It's things like chrome and nickel that cause issues.

High carbon steels generally weld before sparking temps; sparking may be too hot.

The size of your billet needs to be proportional to the size of your forge.

taller stacks are generally easier to weld than wider stacks.

I tend to start at one end of the stack and proceed to the other, (cooler end first if it's all are welding temp; hotter end first if only some of it's at welding temp.)  Firm not sharp blows to set the weld.  After it's set you can hammer hard on it; though usually not on the sides till you have worked it a bit.

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One pieceof advice I have to add that may be of some help:

I have only done a few (7-8?) stacks of 'damascus' and I am fairly inexperienced, but one easy to notice thing for me was the feel of the steel under the hammer when setting the welds. To me I could feel a change in resistance and rebound with the hammer as the spaces between the layers would vanish, I would almost describe it as the billet becomes more firm as the welds are set. So my process while overlapping blows was to also take a mental note of how each blow felt as I moved down the billet. If an area felt too 'soft' I would back up and go over it again before continuing down the billet. In my mind, imagining the steel and knowledge of how the physics of materials work, if a spot felt soft, then there was still space between the two materials and therefore a pocket that must be expelled by pressing the steels together in a directional manner.  

I'm very limited in my experience, but I do enjoy sharing what I have learned. The change is quite subtle, but if you pay attention you can probably feel it. 

As a side note, my last stack was probably a little too big for my own experience, but I did it anyways. I had one spot that on the 2nd welding pass that still felt soft... I decided to give it a really good whack, about twice as hard as all the other hammer hits. Well there WAS a gas pocket trapped in there, and it made its way out the side, at probably 4X the speed of sound as I thought someone shot a 300 Weatherby next to my head. Scared me, ears ringing for 5 minutes, neighbors coming out to look around, and I wear earplugs most of the time in the shop. I wonder if some flux was trapped and vaporized? or a hot gas jet met atmosphere and just detonated as the gas mixed with oxygen? I don't know, but I will take a LOT more care to have good control and overlapping hammer blows in an attempt to NEVER have anything like that happen again.

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Hey Thomas Powers, why do you think the whitlox is not a good design, i have basically gather all the material to build something almos identical, in the intermediate size of their mini and the full size, haven't welded the parts so it's not finished yet, but im now skeptic on finishing it.

i have plans to build at least another one, propane fueled in the immediate future though.

what issues do you see in the design?

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lets see it takes a fuel pile about a dozen times the mean fuel size to get to a reducing zone and then you need more fuel on top of that---try it with their design cold! (value is based on calculations for a bloomery listed in "The Mastery and Uses of Fire in Antiquity", Rehder.)

Compare it with charcoal forges that have been in use for over 2000 years and see how they differ. Do you think that after 2000 years of building forges that could be easily modified by the users that design would not have been tried?

I think they would make a better coal or coke forge myself; of course I burn my wood in a separate fire and transfer the hot coals to my forge as needed MUCH nicer not to have to deal with the heat and smoke up close and personal!  I started forging with charcoal in 1981; used to make my own in my backyard in the city...

I would suggest building an adobe forge or even a Tim Lively Washtub forge and experiment until you learn what works best for you.  The Tim Lively washtub forges have been around for a couple of decades now.

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I built a trough forge after seeing the Whitlox design. I wanted to have the ability to make a long fire. The first fire I built in it was coal. Big mistake. Clinker (slag) stuck to the fire brick, and if i had continued it would have been ruined. I haven't tried wood, only charcoal. The ash clogs it up too quickly making fire management a chore. The "v" shape just funnels the ash right into the tue holes My forge is not an actual Whitlox, so i can't say much regarding them, but I'm planning to make a JABOD for charcoal. All I've read and common sense tell me to go side draft not bottom draft, and I've dug up plenty of clay to make it with. I will probably redo my first forge sometime as well, which has too deep of a bowl, but otherwise burned coal adequately. That one is bottom draft so I don't want to use charcoal in it.

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Sure 2000 years is more than a good time to trust Thomas. From my limited experience using just wood in the forge ( use what you got before you figure out that that wont work) it can get up to heat if one allows the fire to burn without turning on the blower for ten min. This builds up a lot of embers and when it is time to get the fire really hot one can turn the blower on again. For it to work the wood needs to be hard wood and 100% dry. Noticed that under those circumstances it does get hot enough to weld. Working on making charcoal all the time because we use it for the soil. But runs out fast too :) Jclonts82 I for one will see what you mean now today by soft vs firm. But the soaking thing I must try out too. Gonna give some welding a try today. 

I just reread everything and man if I may say so without coming of wrong this is some good usefull info. 

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I agree with Thomas, But a wood forge can work.. 

 

The Whitlox design will work for most people as most won't know it's marginal as there simply isnt enough room to hold all the needed wood before it turns to charcoal.. 

Ideally you need a firebox or feed chute to feed the wood in at a large enough volume to create the correct amount of charcoal needed for the job at hand before being turned to ash. 

a ratio or 4 or 5 to 1 in feed rate is about right for soft hardwoods..   4 to 1 for white oaks or harder woods..    So ideally the forge would look more like a wood stove  at the top, tapering at the bottom with a firepot to direct the coals into the center for maximum heat density zone.... Ideally also in a side blast design vs bottom blast as this would allow for cinder and soot to help insulate the bottom.. 

The wetter the wood the higher ratio to feed rate is needed.. 

 

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Charcoal isn't hard to make, if one looks at what the black powder guys are doing (making high quality willow charcoal) infact it's rather an art form in Japan. They cut thumb size regrowth sustainably and use kilns to make it. 

I have a Wilton style forge I built, a fuel hungry beast, but useful for heating larger stock than my typical charcoal forges will handle. I typicaly use softwood scrap to fire iit and to make charcoal for forging. I find the lower amounts of ash a benifit. Tho I admit to a lazy streak and am happy to use Thommas and Frosty's method of keeping a separate fire going to Prada every hot embers (no, the Tom&Jerry image did not except me) 

for general forging, tho indirect charcoal making is more efficient. 

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"The Devil wears Prada every hot embers!"     Coppicing of woodlots was a standard method of providing sustainable wood in Medieval Europe. When I was trying to recreate some medieval items I was able to make use of coppiced woodlands---of course they didn't know that they were doing that.  In Ohio they were areas under high tension power lines that they cut off every X number of years.  In NM it is along the banks of irrigation canals out here that they cut back every year or two producing marvelous materials for wattle work!

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Did a lot of willow coppicing back in Ireland meself. Here we use the funnel shaped pit method to make charcoal. You just keep layering new material on to the fire and it excludes the O2 as it burns the top most layer. Having the funnel shape is important to allow the air to get into the pit though. Every thing is easy enough, but it all depends on what you have available. For instance I have 5 big mounds of coconut husks (minus the inside shell) available. It does not burn very hot when it is made and also I would wager that it makes not such a good charcoal for use in a forge. It is a very soft wood. What are your opinions on charcoal made from soft wood vs charcoal made from hardwood. 

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21 hours ago, Jclonts82 said:

One pieceof advice I have to add that may be of some help:

I have only done a few (7-8?) stacks of 'damascus' and I am fairly inexperienced, but one easy to notice thing for me was the feel of the steel under the hammer when setting the welds. To me I could feel a change in resistance and rebound with the hammer as the spaces between the layers would vanish, I would almost describe it as the billet becomes more firm as the welds are set. So my process while overlapping blows was to also take a mental note of how each blow felt as I moved down the billet. If an area felt too 'soft' I would back up and go over it again before continuing down the billet. In my mind, imagining the steel and knowledge of how the physics of materials work, if a spot felt soft, then there was still space between the two materials and therefore a pocket that must be expelled by pressing the steels together in a directional manner.  

I'm very limited in my experience, but I do enjoy sharing what I have learned. The change is quite subtle, but if you pay attention you can probably feel it. 

As a side note, my last stack was probably a little too big for my own experience, but I did it anyways. I had one spot that on the 2nd welding pass that still felt soft... I decided to give it a really good whack, about twice as hard as all the other hammer hits. Well there WAS a gas pocket trapped in there, and it made its way out the side, at probably 4X the speed of sound as I thought someone shot a 300 Weatherby next to my head. Scared me, ears ringing for 5 minutes, neighbors coming out to look around, and I wear earplugs most of the time in the shop. I wonder if some flux was trapped and vaporized? or a hot gas jet met atmosphere and just detonated as the gas mixed with oxygen? I don't know, but I will take a LOT more care to have good control and overlapping hammer blows in an attempt to NEVER have anything like that happen again.

J: The gun shot BANG isn't uncommon forge welding, it's junk being expelled from between layers. Make your layers cleaner so you don't need so much flux and it's much quieter and you don't get the BIG fan of molten borax spraying around the shop. A good blow pattern to set the welds works for me. I like my welding hammer with a little more crown on the face than my regulars. My pattern starts in the center of the billet OR at the handle if I welded one on. If the billet is only 2" wide I can start in the middle and work outwards but if it's much more than 3" I have to work outwards from a center line. One on the line then one on each side, then up the line, center, right left, then down the line from center. Alternating up and down the line could be unnecessary but it's a habit. 

Bubbles are indications of junk that was trapped by the weld and if it's actually a bubble then it was probably liquid. (flux) That is probably a hammer pattern issue.

When I weld I'll take the joint to the belt sander if possible, flux cold and close it up as cold as possible. I know fluxing the outside at orange heat is "traditional" but I have better luck if the joint is shiny clean and the flux is present to melt and form a prophylactic barrier against oxygen at as low a temperature as possible. The warmer things get the more chemically reactive they are and  you're trying to prevent oxydization so stop it as soon as possible. If the join is clean then there isn't anything needing a hard squirt of liquid flux to flush out. (Flux means Flush, old English I believe BTW.) Anyway, that's how I weld if at all possible.

This method works well for spring to spring welds but you have to wipe the freshly sanded joint with an oily rag, chrome oxidizes VERY quickly especially when hot enough to melt flux. 

I started using this method to weld before I learned how real blacksmiths do it.

Frosty The Lucky.

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Thank you for confirming that, I guessed it was junk/flux finding its way out. I had no problems with the original stack, or after i cut into 4 then stacked again, it was on the third layer increase where I hot-cut 2X and Z folded into 3rds. That is where the mini explosion happened. 

I usually start at the handle end and work away from me too.  In doing the Z fold I closed a loose end on one side, while forming a pocket where the hot-cut folded part was. I believe thats where the pocket formed. Regardless, I think until I have better control and experience with hot cuts, I will square, cut, grind, then restack from here out. 

 

 

GREAT ADVICE on a more crowned/rounded hammer to help extrude any flux outta the weld. I had never thought to do that. Guess I need to customize one of my hammers. Again, Thank you. 

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Oh great, the Z fold. How can you drive the junk away from a trap in a Z fold? Wherever you start you're driving junk AT a fold or weld. 

Clean, Clean, CLEAN and a drop of oil so there's nothing to drive out of the joint maybe. 

Frosty The Lucky.

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"...What are your opinions on charcoal made from soft wood vs charcoal made from hardwood. ..."

I believe Japanese blade smiths use softwood charcoal, maybe someone could confim that.

I find softwood charcoal tends to light easier, but hardwood lasts  longer. As regards whch burns hotter, I don't believe there is an appreciable difference as the air flow will have a greater effect on heat in a forge. How you make and use the charcoal is likely to have as much or more of an impact on it's properties, I much prefer to use well seasoned wood simply because the process requires less heat value to achieve completion and producess a greater yield per load.

I make my own charcoal from mainly Willow and a little Eucalyptus, oddments of other soft and hardwoods on occasion such as Privet, Rose, Brier, Mahogany, Ash. various conifers, Pine etc.  I do have some commercial lumpwood which I have recently discovered is imported from the far east so have no idea on species. Appart from the shape of the origin material I cannot tell any one from another either in hand or fire. At  the end of the day any char will suffice, some may be better than others and spit less, but what you can get locally or freely is what you will ultimately use.

 

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Ah, the old hardwood vs. softwood charcoal debate. Properly made both are relatively pure carbon, hardwood contains more minerals but that just means more white ash. Hardwood is denser so it was favored in the day volume determined how much a shipper could carry and sell. Lb for lb. the BTU content is the same but when you look at volume more dense means more BTUs per cubic foot. At bloomeries, foundries, etc. denser meant less handling per BTU.

That made hardwood charcoal more economically profitable all round. 

Well, then there's the physics of the stuff. Being denser means fewer voids between particles. Why does that matter? Well carbon is carbon so when it burns it releases X btus. per unit. In many cases the total BTUs are what count but in others how fast it's released is what counts.

Less dense softwood charcoal has more voids which equals more surface for overall volume. More surface area means more contact with oxygen so it burns faster. Faster burn means more BTUs per second released means hotter fire.

Hardwood lasts longer but softwood burns hotter. That's measured temperature NOT total energy per lb.

Frosty The Lucky.

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In a bloomery or blast furnace (yes the early ones ran on charcoal!  Abraham Darby in the 1700's figured a way to smelt iron ore with coal by using pre-coked  coal in the blast furnace; prior to that it was all charcoal!) the crush resistance of the charcoal was an important factor!  So hardwood charcoal was preferred.

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3 minutes ago, Frosty said:

Ah, the old hardwood vs. softwood charcoal debate. Properly made both are relatively pure carbon, hardwood contains more minerals but that just means more white ash. Hardwood is denser so it was favored in the day volume determined how much a shipper could carry and sell. Lb for lb. the BTU content is the same but when you look at volume more dense means more BTUs per cubic foot. At bloomeries, foundries, etc. denser meant less handling per BTU.

That made hardwood charcoal more economically profitable all round. 

Well, then there's the physics of the stuff. Being denser means fewer voids between particles. Why does that matter? Well carbon is carbon so when it burns it releases X btus. per unit. In many cases the total BTUs are what count but in others how fast it's released is what counts.

Less dense softwood charcoal has more voids which equals more surface for overall volume. More surface area means more contact with oxygen so it burns faster. Faster burn means more BTUs per second released means hotter fire.

Hardwood lasts longer but softwood burns hotter. That's measured temperature NOT total energy per lb.

Frosty The Lucky.

+1  yup what he said... I prefer softwood charcoal when working Japanese style blades especially for hardening..

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1 hour ago, ThomasPowers said:

revolution In a bloomery or blast furnace (yes the early ones ran on charcoal!  Abraham Darby in the 1700's figured a way to smelt iron ore with coal by using pre-coked  coal in the blast furnace; prior to that it was all charcoal!) the crush resistance of the charcoal was an important factor!  So hardwood charcoal was preferred.

Abraham Darby first used coke to smelt iron in January 1709. He had access to low sulfur coal for coking purposes. It could not have come at a more opportune time.

England was running of forests by the sixteenth and seventeenth centuries. So much so that strong laws were passed to protect tree for the use of the British navy.

Needless to say, the price of charcoal kept rising during those years.

Coke had already been used to smelt brass milling machinery in the grain malting factories for beer making.

Indeed the malters used coke in their malting process. (the sulfur dioxide produced in burning of COAL meant that it could not be could not be used for that purpose, as it would contaminate the malt).

Mr. Darby was aware of that brass smelting use of coke.

He, himself, also had a hand in such casting of brass using coke.

He patented sand casting of cast iron about 1705. (his apprentice, John Thomas, devised this process and the particular molds that were used).

His cast iron pots & other products were thin and strong enough to begin a cast iron implement revolution in England and elsewhere.

Sadly, he died in 1718 at 38 years of age.

I honor such extraordinary men.

SLAG.

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I love the old history stuff.. 

In the town where I grew up they had a village called old furnace which supposedly made cannon balls during the revolutionary war.. 

Not quite sure as I believe it or not since there is also a landing zone called New furnace where there was a cast iron or smelting furnace.. This was right on the river and to this day you can walk the river and pull out pieces of lime stone and fragments of slag and iron and charcoal from where they just dumped the remain part of the charge.. 

The  town eventually built a rail line over the sight and ruined any of the building structure so all that is left is the slag dump.. 

There is still an old foundry in town which went out of business back in the late 80's and in the early days there they also dumped all the slag directly into the river.. 

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