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Getting Started Forging

Posted by Nothingman 
Getting Started Forging
March 08, 2016 03:26PM
Can anybody point me down the right path to getting started forging? I found that Murray Carter offers a school for this, but it is quite cost prohibitive at this point. Any thoughts?

Also are there any real performance benefits that are gained from forging other than being able to forge weld laminates and not having as much mess (I would imagine anyways)...?



Edited 1 time(s). Last edit at 03/08/2016 03:27PM by Nothingman.
Re: Getting Started Forging
March 08, 2016 05:16PM
Biggest benefit seems to be in more efficient use of steel...if forging to shape you can save yourself a lot of grinding (especially with odd shapes) and also make use of smaller pieces of steel.

_______________________________________________________________________________________________

Always in search of a good choppa'
Re: Getting Started Forging
March 09, 2016 07:41AM
nothingman,

getting started in forging is pretty easy. get a heat source, coal, charcoal, propane, waste oil. find something to burn it in. find a hammer and something mostly solid to hit the hot steel on and away you go. ear plugs, safety glasses, gloves, and a way to hold that hot steel while you are working it in would be good ideas also.

sure there are benefits to being able to forge. besides the excersise. you can have a lot more freedom in what you can make. now a lot of that applies to making knives out of salvage materials like leaf springs, coil springs, lawnmower blades and such. but even when you purchase new steel sometimes you may not have the right stock to just grind your knives out. like say you want to make a large chopper with an integral guard. the width of the guard will be 3", but you only want the blade to be 2" wide, and only have 2" wide steel. you can hot cut the guard from the handle, then bend it up to form the guard. this would save a lot of time and material vs buying a 3" wide piece of steel and grinding what you don't want away. or you need to make a little wider blade on a 9" chef than what you can fit into a 2" bar, just heat it up and stretch some of the material that you were going to grind away anyhow into the wider portion that you need.

or yesterday, I turned a piece of 1" 52100 round stock that was about 4" long, into a 9" chef 2 1/4" wide, with a hidden tang. it would be pretty tough to do that without forging.

for the performance part, while I do believe that the forged blade has the potential to be a better blade, there are a lot more ways to screw it up during the process.

plus you have a whole new skill set for making shop tools. need a cold chisel of a certain size? grab a piece of an old coil spring, and about 20 minutes later, you have it. new set of crucible lifting tongs for the foundry? couple pieces of rebar and some other scrap and away you go. how about a specialty wrench for holding the water pump pulley on your truck still so you can take the holding nut off? take an old lawnmower handle, straighten it out, forge the points, then bend them to 90 degrees, then bend the whole thing in the middle, set your spread on the points, and get that truck back in service.

Performance above all else!!!
CaltonCutlery.com updated 5-22-15
CaltonCutlery@yahoo.com
Re: Getting Started Forging
March 10, 2016 11:04AM
Joe, can you elaborate more on how forged blades can be better? It will be really interesting to hear.
Re: Getting Started Forging
March 10, 2016 12:38PM
nattypringles,

sure, but its more of a thought than anything ive proven or anything, so you will have to take it as what it is, just the ramblings of a maker who has seen some odd things that I haven't seen explained anywhere.

so lets say you start with 2 big chunks of steel at the mill, after they have poured or cast, but before they start the rolling process to get them down to something that we can work with in our shops. ive seen youtue videos where these things are huge, several hundred pound chuncks of steel. now assume that both chunks are identical in chemical composition. and lets also say that at the mill, where they roll the steel into sheets, that the higher the temp that they can run it through the rollers at, the more they can work it with each heat, the less stress that gets imparted to the rollers, and besides, there is a pretty big lag time from the time they pull it from the furnace and get it to the rollers that is just lost heat, so they would have to heat it hotter to compensate for that. now lets follow the 2 chunks:

lets also say that the end product will be a standard 1/4" thick hunting knife out of a carbon steel of your choice. so we go from the big chunk, down to that particular knife. but with the difference being the size of the steel that the smith starts with as he gets it from the mill.

1. start with the big chunk, and the mill rolls it down to say 5/16" hot, and then rolls it that final 1/16" cold, and anneals it, shears off sticks, and ships it to the suppliers, who then resell it individually to the smith. this steel has been rolled almost to its final dimension under the higher heats that the mill would use to prolong the life of their rollers.

2. the second big chunk gets rolled down to thicker sheets, say 1/2" or into bars. then cold rolled to final dimensions, and then shipped to the suppliers.

now lets say the same smith makes a knife from the first bar, and just grinds it to shape, and heat treats it.

the same smith takes a 2" round bar from the second chunk, and forges it to shape under much lower heats than what the mill does, as he is working with presses, power hammers, and such and can take more time and works at lower heats. this blade will have more controlled thermocycles than the first. plus the steel that is in the center of the bar, that ends up being the knife, will have been protected by the higher heats by the steel on the outside of the bar and I think in a better condition to be a good knife.

when I came up with this thought, it was when I was working with a lot of 52100, I was getting that 52100 from McMaster carr in either 5/8" round or 1" round. not once did I ever have a blade from the 5/8" bar outcut one from the 1" bar and I wondered why. and this is about the only thing I came up with, assuming that the steel in each bar was roughly the same composition, and rolled by the same mill.

now whether its the thermocycles or the actual forging I don't know, but id lean more towards the thermocycles. one of these days I'm going to take a piece of 1" round stock {or maybe it would take 2" round so the cutting edge would come from the center of the bar}, and cut the sides off one piece and do a stock removal knife with it, and forge a knife out of the other end and test them against each other and see what happens.

but even at that, there are a ton of ways to screw up the forged knife. get it too hot, work it too cold, forge the scale deep into the surface forge too much on one side and not the other, ect.... which is why I say " I think the forged knife has the potential to be a better knife, but there are a lot of ways to screw it up first". and there are a ton of assumptions in the whole thought, and you know what assumptions do.

there is also the thought that the blade that is forged to shape is much like a lifting hook on a large crane. in that if you forge it to shape, the grain of the steel runs with the hook, but if you just grind a hook out, that the grain would run crosswise to it where it would be the weakest. now how much that would really matter, and how much of it you would be able to see in actual use with a knife I couldn't tell you.

and cliff or me2 or one of our resident metallurgical guru types could probably either say "there might be something to that" or "joe has finaly gone off the deep end" or "sure here is a paper or study where they proved this one way or another"
Re: Getting Started Forging
March 11, 2016 01:30PM
hi,
perhaps with 52100 all the thermocycles may make a difference. on KD there is usually discussion when NJSteel Baron gets a new batch of 52100 about normalization and other thermo cycles before final heat treat. on the other side, when using known source tool steels, Roman Landes and others recommend not thermo cycling. ref: [www.hypefreeblades.com]
on steel having grain, which "grain" pattern do you orientate to? the tool steel i use must be cross rolled. i cut my blade so the "grain" ran left/right. after some sanding with fine grit paper the left/right grain was replaced by vertical grain. go figure.
Nothingman: i would browse YouTube. here is a good one with pictures and explanation [www.cashenblades.com] from watching others, looks like the best way to start is to get an old lawn mower blade or leaf spring to learn how the steel behaves. enjoy
scott



Edited 1 time(s). Last edit at 03/11/2016 01:42PM by oldsailorsknives.
me2
Re: Getting Started Forging
March 15, 2016 06:53PM
Quote
Joe Calton

1. start with the big chunk, and the mill rolls it down to say 5/16" hot, and then rolls it that final 1/16" cold, and anneals it, shears off sticks, and ships it to the suppliers, who then resell it individually to the smith. this steel has been rolled almost to its final dimension under the higher heats that the mill would use to prolong the life of their rollers.

this blade will have more controlled thermocycles than the first. plus the steel that is in the center of the bar, that ends up being the knife, will have been protected by the higher heats by the steel on the outside of the bar and I think in a better condition to be a good knife.

there is also the thought that the blade that is forged to shape is much like a lifting hook on a large crane. in that if you forge it to shape, the grain of the steel runs with the hook, but if you just grind a hook out, that the grain would run crosswise to it where it would be the weakest. now how much that would really matter, and how much of it you would be able to see in actual use with a knife I couldn't tell you.

and cliff or me2 or one of our resident metallurgical guru types could probably either say "there might be something to that" or "joe has finaly gone off the deep end" or "sure here is a paper or study where they proved this one way or another"

While higher heats certainly make for easier rolling, I don't think its as simple as just using higher heat to make it easier on the rollers. That said, I feel sure Joe is making a simplification for the sake of example. Also, while surface scale, decarburization, and other things will certainly affect the surface, I'm not certain that the use of higher temperatures during rolling is inherently bad for the steel, thus requiring the center to be protected.

As with forging, even rolling mills get it wrong and I've seen some impressive flaws in rolled plate. I think it needs to be stated that we are assuming both the rolling and forging are done correctly when we make comparisons like this. Non-destructive testing is employed for both products to ensure flaws from both processes are kept to a minimum. The example of the crane hook is a classic in engineering texts and a great case for the advantage forging can have when properly employed. It's analogous to steam bending wood rather than just cutting the curve. Since blades are typically relatively straight, I, like Joe, am not sure if the advantage is realized in knives, and even in the case of severely curved blades like scimitars, it may be a case of forged is 9, stock removal is 8, but we only need a 6. I prefer to use the term mechanical fibering when describing the flow of different directional properties imparted by rolling or forging. It helps keep me from mixing grain flow up with the actual grains of steel. I have heard of makers orienting the edge of their knives parallel and perpendicular to the rolled direction and being able to tell a difference in use. I've never tried it personally, but there might be something to it.
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