How to forge (Techniques)

[Arthur]

http://www.americanbladesmith.com/ABS_School1.htm

 

 

If you have the time [2 weeks] and the money [$700 plus transportation and lodging] this is the place to be!!! When you leave you will know how to forge knives!!

 

Teaching yourself is very challenging....you're off to a good start...keep at it!!!

[Dee]

first thing i see if a whole lot of potential for flying fibres with all that exposed wool ..

this stuff is really nasty for your lungs and can really seriously harm you ..

if you arent going to coat the wool in anything .. then at VERY LEAST get the best respirator you can possibly find and wear it at all times around this thing.

 

the ceramic wools tend to be made from a form of silicate ... and it can and will get inside and end up as silicosis.

its real, it happens.

dont think that just because you cant see it its not there.

please.

 

the itc type clays dont cost That much .. and you obviously have the handy skills to put something together that will contain and seal the wool after from your breathing space.

 

can you run down how your forge is put together ... cause i cant really see 100% as whats going on ..

do you have a regulator on your tank? ..

 

am i right in saying that you have connected a pipe direct to the propane tank ... which leads to a modified gas torch that is putting gas into a pipe .... which has a hair dryer attached to it ... and all of that goes into the insulated chamber? ...

is that it?

[Geoff Keyes]

I use 1/4 inch line for my gas line, and a 1/4 inch needle valve for control, more than that you don't need. You should be able to freeze the tank valve pulling fuel out with that setup.

 

Bright yellow in the sun is plenty hot, probably hotter than you really need. Take a cardboard box, or a metal bucket and shade the piece with that, then what color is it? If you see sparks popping off of the surface, you are WAY too hot. You might want to try a bit less steel ( I know we all suggested this, and I know you wanted to go big) but you would probably have more success in the short run, which leads to more success in the long run.

 

Get hold of some coil spring, you know that it can be hardened because it's already hard. If the piece is small enough to put in your forge you can heat a big piece of it, drop it over a bar clamped in a vice, grab the end with a vice grip, and walk away. You can pull out 20 feet of steel this way, easy.

 

A 1/2 inch coil can make 1 inch wide blades without too much work, and it's pretty easy to flatten out the pieces, you don't even need a buddy with a 15 lb sledge.

 

Geoff

[Kurt]

Dee: I'll try to find something soon. But I'm young and immortal still, and I've sunk nearly $400 in to this adventure already, with no profit yet, or for a few weeks to come. Some of that would be nice first. Also, you got it. Tank => Modified torch valve => 1" pipe with two hairdryers => furnace chamber.

 

I look forward to blowing you all away with my first knife. I hope I can.

 

Geoff: I actually have a spring from my Honda Odyssey lying around in the garage. If I can't make sheet steel budge, it's going to be hell to straighten that thing out and then flatten it. It's at LEAST 1/2" steel, possibly 3/4". But there's no way in hell I can just stretch it out, I'd have to cut it in to pieces and work with small chunks.

 

Tomorrow I'm not doing anything, (my wrist is still a bit stiff for fruitless endeavors) but Thursday I will get back to forging, and I will be carefully watching the furnace in case something goes wrong. It's capable of getting scarily hot now, and I hope the setup can take it. I know for sure it gets to at least 1000 C throughout, which, according to http://ajh-knives.com/metals.html, is within the forging range of spring steel.

 

Is that piece still usable? I was thinking I'd flatten it out, finish the tang, and cut the rest in to shape. At least then some of it won't go to waste.

[Geoff Keyes]

Just saw the pics, Dee is right. You need to cover the exposed wool somehow. The fibers, (or fibres if you prefer ) , are microscopic, are really bad for you, and bad for anyone around you. You would do as well to stack some fire brick in front of the opening, I'm not sure your door is helping much.

 

You are plenty hot, much hotter than I like to forge. Your fire has too much air and not enough fuel, this is called a oxidizing fire. Scale and rust are the same thing, one is just much faster. You are losing 1% or better of your steel every time you take a heat in an oxidizing flame, not to mention that you are burning carbon out of the steel. It is possible to burn so much carbon out of the steel that you can't heat treat it.

 

What you want is a bit of flame coming out of the door. This means that all of the air in the chamber has burned and the excess fuel is igniting as it hits the outside air. This prevents the really excessive scale you are showing us in your pics.

 

You also need to get a regulator for your tank, and you need to do it RIGHT NOW! You probably won't get a flashback up the hose, but we would all feel pretty bad if we heard that a young man in Canada was killed in a propane explosion. This is serious. There are lots of places where you can skimp and scrounge stuff. THIS ISN"T ONE OF THEM.

 

Geoff

[Kurt]

I've lit the end of the propane outlet. It makes quite a flame, but nothing is going to go to the tank. Guaranteed. I've taken the valve apart thoroughly, the flame needs to get through a 1mm hole in order to reach even the hose. The higher pressure zone means the flame isn't getting past there. This is assuming the flame makes it down to the torch with the hairdryers running. Even then, the forwards pressure of pure propane will douse the fire. I've actually TRIED to get this setup to light on fire anywhere but the top, many times, some today. It's relatively safe.

 

Mind you, that doesn't mean I'm going to ignore the risks. Especially with this modification, I'll keep a good eye on it. Don't worry about me, I didn't just throw this together without an eye for safety.

 

I didn't think I wanted any flame out the door. There's a point of maximum heat, which can be seen on the kaowool as it instantly changes from yellow to white to really white to white to yellow as you adjust either the propane or fans past the adiabatic zone in either direction. I spend a good ten minutes every time I light the thing getting to this perfect balance.

 

Today, however, I just let 'er rip. I had the fan and propane on full, and luckily enough, it appears the fan is once again the limiting factor. Also, at that temperature it was hard to tell where the adiabatic point was.

 

Mind you, I ordered a thermocouple from eBay. It should be here in a few days, and then I can accurately say which point is hottest, which means no wasted propane, and no oxidation.

 

What was bubbling? Was that the iron oxide?

 

Also, how's this: http://www.canadiantire.ca/AST/browse/3/Ho...%2B710%2BmL.jsp

 

I was told by the refractory guy that this was essentially a grout marketed as something a little bit more. But a thin layer might do the trick?

[Dee]

ok .. Kurt, my man .. if you want to turn a profit .. there are a few things you need to consider.

 

first and foremost is your ability to keep yourself alive long enough to do so.

 

its ok to look at the figures and say that you are too much out of pocket ... but you really need to take it seriously in terms of safety.

you are learning an incredibly complex art/craft here ... the more you forget about trying to make a profit asap .. the better it will be on you and your skills.

 

you dont just want to turn a quick profit on knives .. if you did, then you would more than likely go off and become a knife dealer or something of the like ..

the actual making of a blade is the part you need to keep in mind more than the profit scale or ratio.

 

yes, the gas would need to travel through a 1mm hole ..

but it Can and it Does.

there are far more impossible things done each and every day.

 

i look forward to being blown away, honestly i do.. we are just trying to say down get blown away yourownself in the meanwhile.

[Arthur]

Rigidzer: http://www.knifeandgun.com/ProductDetails.asp?ProductCode=IT

 

 

This is sprayed on the isowool inside a forge to protect it..perhaps you could spray it on the outside of your forge to protect your lungs as previously mentioned....My father worked in a shipyard at the outset of WW2 and the asbestos fibers came back to haunt him as he aged...

 

Also as previously mentioned,even real tongs made for knifework can be a pain...your much better off using a longer piece of steel or welding on rebar...

 

As Geoff showed in his video an angle cut in the front of the bar can be a real help,If you stay with a rectangular piece at least radius the corners to help avoid the dreaded fishmouth..

 

A 4# hammer is too heavy to learn with....stay lighter and practice hammer control..

 

And don't worry too much about your first few knives really looking like knives, your learning a skill.not producing masterpieces.....Me and I guess many others spent a few years forging "Christmas Presents" before we made knives we actually wanted to put our names on.But then again I'm a slow learner and have to be shown what to do.

 

Your off to a real good start...stay with it and don't get discouraged....Keep learning..

Edited June 10, 2009 by Arthur

[Geoff Keyes]

I think I may not have been clear.

 

I didn't think I wanted any flame out the door. There's a point of maximum heat, which can be seen on the kaowool as it instantly changes from yellow to white to really white to white to yellow as you adjust either the propane or fans past the adiabatic zone in either direction. I spend a good ten minutes every time I light the thing getting to this perfect balance.

 

Today, however, I just let 'er rip. I had the fan and propane on full, and luckily enough, it appears the fan is once again the limiting factor. Also, at that temperature it was hard to tell where the adiabatic point was.

 

You do want flame out the door, it's called a reducing flame. It's not that you want a plume of fire 3 feet long out the front of the forge (which is uncomfortable in a tight space) you want a soft greenish (which will be hard to see in the bright sun) flame which indicates that all of the air in the combustion chamber has been used up. This will give the minimum scale. It's not that most of us want to get every last BTU out of our systems, we want to get a predictable and controllable forge. Mine is such that I can tell the state of the fire by listening to the sound the burner makes. A hard, crisp note means that I have an oxidizing, scaly fire. A softer, more muffled note is the sweet spot, a nice soft flame out the door, and very little scale. Because my forge has a fair amount of head room in terms of performance, that sweet spot can be adjusted up and down 5 or 600 degrees (F) by a couple of simple changes.

 

If you are running the gas flat out with no regulator, your line pressure should be something like 20 psi (someone please check me on that, I don't run small tanks anymore). I'm not surprised that your hairdryers are maxed out.

 

I run my vertical forge (which is about the same internal cubic as yours) at 1 psi line pressure and regulate the gas to the burner with a needle valve, so I'm running between 4 and 8 ounces of gas pressure to the burner, and it still is a bit hotter than I want much of the time.

 

One of the benefits of ITC-100, aside from the safety issue with flying fibers, is that has a high level of zirconium in it. The zirconium reflects 98% of the IR that hits it, improving the efficiency of the forge by a large factor.

 

Geoff

[Matt Bower]

High pressure regulators aren't that pricey, and that way if you manage to drop yellow hot steel on your fuel supply hose at least you won't have a flamethrower at unregulated tank pressure (which can easily be well over 100 psi, depending on a lot of variables) emerging from the melted end. You'll also be able to achieve consistent gas flow as pressure in the tank changes over time (which it will do).

[Kurt]

Fair enough.

 

I assume I can get the regulator at any old hardware store. How about that coating, though? Where do I find that? (Tomorrow you'll see pictures of my second attempt at forging)

[Geoff Keyes]

ITC products and regulators and stuff

 

Geoff

[Michael Pyron]

Tomorrow you'll see pictures of my second attempt at forging

 

There's really nothing wrong with the piece you were forging on, it just needs to be forged more, you're already off to a start with that one, but if you want to try with a smaller piece or something I guess I can understand that.

[Matt Bower]

Agreed. Don't give up now -- you've just started making progress on that piece! (But grind out that nasty bird's mouth. Or cut it off.)

Edited June 10, 2009 by Matt Bower

[DJPratt]

People have been telling you how we do it this whole time.....

 

Get a regulator and a needle valve it will cost you less than 50 bucks.

 

There are reasons the people here do things the way they do its because its safe and it works. So not only will you work more efficiently you will continue to be alive.

 

While i dont pretend to be any where close to the skill level that is present on these forums the difference in quality i can see between each knife i do is immense, and i attribute that mostly to carefully reading this sight. Don't rush in to things go back on the forum and dig read every post you have time to, and dont expect to make money right away (you might sell a knife for a 100 bucks but if your any thing like me i has 20 hours of work in it) its about the love of the craft not just making a quick buck.

 

 

Good luck

 

~~DJ

[Stewart Light]

Kurt,

 

Is your end goal here to have this as a source of income or is it just a hobby?

[Doug Lester]

As mentioned, you have two major safety factors, no regulator on your tank and exposed ceramic wool insulation. You need a 15 psi regulator for a blown forge (anything above that will also work) and you are exposing yourself and others around you to silicon particles from the heated ceramic wool in your forge. A ball valve on the line would be good for shutting the forge down in an emergency. You may consider yourself young and immortal, but I used to work in a walk in medical clinic and I ran into several men who have perminant injuries because they wouldn't listen to what more experienced people told them. Most of them ended their tale with the comment that they now wished that they had listened to what they had been told..

 

It would be exceptional if you were to make a knife worthy of selling on your first attempt. You will be doing good to make one that is worth giving away. Mine is hidden deep in a drawer. A Y chromizome does not give you the ability to make knives. Only study, practice and time will give you that ability. If you try to short cut things you will set yourself for failure. It's not uncommon for someone to study this craft for two, three, or four years until s/he sells their first knife.

 

Doug Lester

[Dave Stephens]

Kurt,

 

If you send me your mailing address I will buy and mail you a regulator. Seriously.

 

Not coating your forge wool is like smoking. It's going kill you, but slowly. Dumb, but your call.

 

Running a forge with nothing preventing the flame from going up the hose to the tank is like Russian Roullete. It'll kill or maim you fast. Really dumb and may hurt others nearby.

 

Go to google images and type in "shrapnel wounds." That propane tank is a whole lot of shrapnel waiting to happen.

 

Still feel immortal?

 

--Dave

Edited June 11, 2009 by Dave Stephens

[Kurt]

Actually, nowadays tanks are designed not to explode, although the resulting flame from a punctured tank would be called an explosion by most.

 

I gotta buy some epoxy still, and some brass. I'll get a regulator then. As for the coating, I'll work on that too.

[Dave Stephens]

Actually, nowadays tanks are designed not to explode,

 

[Greg H.]

Actually, nowadays tanks are designed not to explode, although the resulting flame from a punctured tank would be called an explosion by most.

 

Please don't believe that!

 

 

A few years ago I worked at a natural gas shaving operation, where they take propane mix it with enough air to bring the BTU value down to that of NG and inject it into the NG line serving the city.

 

Despite all the safety measures, a tank explosion was their biggest fear, and because of that they had concrete barriers between each group of 6 tanks - simply put there motto was " not if but when " and worked on the presumption that a fire was going to break out..

 

My job at that place was after hour leak detection and fire watch, and I about went ballistic early one morning when I was out on patrol:

 

I had just crossed in front of the tanks and was walking on the hill behind them and heard something sounding a poorly tuned jet engine.

 

I was just high enough to be able to see just over the top of the 2nd row of tanks but not quite high enough to be able to see the tops of the 1st row of tanks that were lower down, and when I heard sound, I looked back over my shoulder to see what appeared to be a 20-30 ft flame ( that was very obviously from propane burning ) shooting up from the tanks - and it was all that more surprised since less than 10-15 min before, I had just walked less than 10 ft from the very tanks, that the flame appeared above and saw no sign of leak or anything else wrong .

 

I didn't waste any time, and just busted out running - thinking I was a dead man as I was 200 yrds from the nearest phone ( which had to come first because it was the closest phone in almost a mile ) and 300 yrds from the closest exit of the facility, where I had to then go to stop traffic on the road, and had just rounded the corner of the nearest building, when the sound of the burning propane cut out like someone flipping a switch.

 

Thinking that was mighty funny for a burning propane tank to do - I stuck my head around the corner of the building and to my amazement - saw no sign of the fire that had been burning less than 30 seconds before.

 

 

Ever so carefully, I started walking down to where I could see the 1st row of tanks - and I didn't see or hear a thing.

 

 

I then walked down to where I could see the front of the 1st row of tanks, and still saw nothing wrong.

 

 

I then proceeded to walk across the front of them ( maybe 20 yrds - 30 yrds max ) so I could get a clear view of all of them and when I had reached a spot about dead center, of where I saw the flame, and saw nothing ---- no flame, no scorch marks, no evidence at all that anything had been burning.

 

I tell you - I was one puzzled SO.

 

 

 

 

I was still facing the tanks and was literally, just about to head back in and make a report - when all of a sudden that sound of a poorly tuned jet engine was back ----- WHAT THE HELL???

 

IT WAS BEHIND ME!!! ..............

 

 

I whipped around to see a hot air balloon rising up out of a depression just across the road.

 

 

It was about as far from me as I was from the propane tanks - all the balloonist was looking at was a nice empty field to take off from - that it was within rock throwing distance of forty-eight 55,000 gal tanks each about 75% full ( about max for propane tanks of that type ) didn't enter into his brain.

 

Sure it's funny to think about it now - shoot it was funny even an hour after it happened, but it sure as heck wasn't funny then, because of the seriousness of the problem.

 

It was pieced together after local law enforcement had a small talk with the ground crew of the balloon.

 

When I first saw the flame, the balloonist had just started his burners, and was adjusting them - thus the reason why I saw a long flame shooting up " from the propane tanks ", and why it took from the time I saw them to the moment I got out of sight behind a building - the tanks, the balloonist, and myself just happened to be lined up to make it look to me that some of the tanks had suddenly caught fire.

 

 

 

 

In a very unique way, the balloonist was very lucky........

 

........had I made it into the building, before he finished adjusting his burners, he would not have had a friendly talk with a single LEO, he would have had to explain his actions to the sheriff, city police, and fire dept, because that phone call, I was going to make, would have activated a contingency plan, that I would not have been able to stop on my own, because it is assumed that I will be out of contact with anyone until the first emergency crews arrived - such is the danger.

Edited June 11, 2009 by Greg H.

[Dick Sexstone]

Kurt,

Looks like you have gotten enough advice about propane and heating .... I would like to address your wrist problem...... sounds like you are swinging the hammer for too long at each heat.... and if the steel was not hot enough you are working far harder than you need to.... when my arm gets tired I start to lose control and to compesate for that I grip the hammer even tighter to get the control back ( So I learned not to do that a long time ago).... this is the worse thing you can do.... If you are still gripping the hammer hard when the hammer hits the steel the mussels and tendons absorb all the shock..... you have already experianced what that feels like..... you only want to grip the hammer hard enough to pick it up but when it comes down and when it makes contact with the steel you want to have a light grip ... you are only guiding the hammer to the spot you want to hit..... let the hammer do the work not your arm.... when your arm gets tired try choking up on the handle.... and when you lose control set the hammer down and take another heat and let you arm rest.... and when your arm tells you( Like you wrist already has) that you have had enough ....listen to it.....stop for the day and do something else.... some of us dogs are old and can still swing a hammer only because we have listened to our body and made adjustments as needed...." it's not nice to fool with mother nature".... All of us were young once and most were foolish as well (they go hand in hand LOL).... and most of us have gotten tennis elbow (smith's elbow) from our huberis.... in the long run you learn to use you brain cause you run out of brawn.... It is good to see you DO as Sam said .... mistakes are the best way to learn .... It only becomes insane when you make the same ones over and over.

dick

[C Craft]

I commend you for jumping in with both feet here. But please take some advice from well meaning folks. I was once young and bullet proof too!

Saftey first, even when you do everything right, sometimes it still can go wrong. Protect eyes and ears when they are gone they are gone.

The unregulated propane is down right dangerous.

The unsealed refractory coating is just plain crazy. The fibers get into the air and you constantly inhale them. Once in the lungs they are there. They don't go away and with time they will imped the lungs ability to expand and allow you to breath, as well as setting you up for lung cancer later in life.

You asked what you are doing wrong and everytime someone mentions the dangers of what they are seeing you basically scoff at them!

 

Take a little time and shut down and put saftey concerns first and then go back and learn what you need to about the actual forgeing of a piece of iron or the wrist may end up being the least of the problems. I am not preaching here just trying to tell you have got your priorities in the wrong order.

 

A racing analogy: "To finish first, you must first finish"

 

The way you are going at it you may cross the finish line but, you are going to kill yourself doing it, and no matter how great a knife you produce it's not worth it!!!!!!!!

[Arthur]

Fair enough.

 

I How about that coating, though? Where do I find that? (

 

Go to the link on post #33

[Kurt]

Okay! Safety soon, I swear. I put some old ducting over the propane line just in case, will soon cover exposed wiring, and address the issue of my tree stump smoking and creating embers from the radiant heat of the blank. And there's the whole "my forge is falling apart and needs a coating to stay together and help me from not dying a painful death" thing too.

 

Apart from that (Which WILL be addressed soon), I made some nice progress. I heated up the steel a little hotter, and managed to hammer out a tang and a little more length in about an hour. But because of the previous hammer dents, I ended up treating it like a stock removal job. I had to get rid of about 1/8" of thickness to get all the dings out. Luckily, it's still a decent thickness for a small knife.

 

Here's pictures!

 

1:20PM, 1:33PM, 1:54PM, 2:04 PM, 4:19PM (Moment of Zen), 5:33PM (Stock removal appears to help me reach that state), 6:05PM, and then shortly after I had to stop for dinner.

 

Any advice regarding adding the blade edges? I was just planning on using the belt sander and going slowly.

Edited June 11, 2009 by Kurt