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A question on the number of heats before light steel eventually becomes burnt and uinuseable.
Lets say I have a 14 inch piece if 5/8 round light steel that I want to make into a kitchen implement. Being a beginner I would need to take more heats on the steel than when I acquire more skill and knowledge. So my question is how many heats would be OK before the steel becomes burnt and useless - assuming a bright cherry heat each time and no forge welding??
Is this an exact science or more experience and observation?

Brian

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blkbear, welcome to the site. It's not the number of heats, it's the length and intensity of the heat. Get the steel nice and bright red-to-dull orange, and hammer away. Just don't let the piece set in the forge long enough to start to throw sparks, that's when the steel is junk. You can heat it as many times as you want.

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You should take the heat up to a bright yellow, not just orange or red. And don't beat on it below an orange. There is much more danger of ruining your work from hitting it at too low a heat than from heating it too often. RED is not hot for mild steel forging.

What kitchen implement are you making? From your concern, It sounds like spatula or ladle work. In that case be VERY attentive to keep your heat between yellow and orange. It is so tempting to keep beating on it because it cools so fast when you have it thin. But put it back in and pull it out before it burns. Know what you are going to do before you even reach for it. Be thinking and feeling the specific hammer blows as it comes out and be swinging as it touches the anvil.

I know, I know. You only asked whether you can heat too often. The answer is yes... but it's not usually an issue. You will normally ruin something with some other form of neglect or abuse LONG before you scale it to death.

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The answer is theoretically "infinite" below scale temps but as the other folks have stated, burning and/or scaling will influence the final result. I have tried to measure the thickness of scale with a micrometer and gotten a number around 3-5 thousandths. If a bar that is .500 in diameter is taken to scaling heat every turn in the forge and the scale is removed once, then an average of .004 x 2 (scale on both sides) would mean you could heat it 62 times before it went away.

In reality, it is not linear and you can lose a great deal more because heavy scale will be thicker, forging will obviously reduce the size, high heats will generate multiple layers of scale, etc. From personal experience, I have also left pieces in a gas forge for a long time and observed much more real reduction in size from scale loss than in the math exercise above, so the reality is that one VERY long and HOT heat may be enough to ruin a piece - even below temps where it is burned.

To answer your question - it's more about experience and observation. As Ed said, get it hot and move as quickly as you can while retaining the quality of the work.

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Check out a book called 'The Blacksmiths Craft' . It's available online (as an Adobe Acrobat pdf file) for free at:

http://www.countryside.gov.uk/Newenterprise/economies/craftpublications.asp

Scroll a third of the way down the page to see the available titles. You want to read through part two of 'The Blacksmiths Craft' specificaly as that deals with heat, colors of heat and what jobs can be done at the different heats.

Hope this helps a little

P.S. There are 8 titles there that are worth downloading and reading and they're completely FREE!!! :)

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Thank you, thank you, thank you. Much clearer now. I will definitely look into those free volumes.

Brian

Listen to Ian and the others and definetly download the books they are really worth having with alot of good info.I'm a newbe to and have learned alot from the gentlesmiths on this site.
As far as burning up steel the only time I burn it up is when I start getting impatient and start cranking the blower to fast especilly(spl) on thin material
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OTAY......you mentioned having 5/8 round light steel. Will assume this is common old manurealloy hot rolled ( probobly 1015-1020 ) steel. Not a lotta carbon in it. Everythings pretty well covered in previous posts. I just have a couple of things. Don't worry too much about the color of the steel in the fire at this stage. Just get it hot and hot until it forms scale on it ( alligator skin if you please). This scale initially will be tight on the steel, evidence being you pulling the steel form the fire and draggin it accross something to see if the scale is loose. Further heat will mean that the scale will loosen eventually. This is the place to forge (when pulling from the fire, the scale should be loose). There are temps that this happens at but we won't be concerned with that right now. Whatever color this is in your eyes, this is what you want. As Hollis said, scale will eventually make the stock lose some mass but no big deal. You can go to this heat with this stock MANY times and as long as you don't go no hotter, you good to go. Heat more and you will eventually damage. If you are using coal and have no forge rake, a piece of this stock would be good for this purpose. Start with a piece a couple feet long. Heat about 6" or so and forge this down flat and go to mebbe cardboard thin (looks like a golf putter in shape). This is then bent at 60-75

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This is a very interesting topic and is best learned at the anvil through trial and error. What I figured out after years of forging is that when you are forging a lot of detail at the end of a piece of stock its best to form the fine detail last. For example, I recently forged a horse head poker and forged the neck and ears too early. Before I could finnish the detail on the horse head, the ears and neck started to erode into the fire. So the best thing to do is try to forge the main profile first and then work on other features in descending order of thickness. But, I also believe that if you have a reducing atmosphere in your fire, less oxygen will be forming with the iron and carbon molecules which is the heart of the issue. Good luck. These types of problems are best mitigated through experience.

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Authentic, I will happily agree with your post. No need for scale in finer forging and I could have gone on for long time in my previous post about this. Sometimes just red is plenty to tune up or move something a little. Many things can be moved at black heat. For the purpose of this thread though, I thought I would try and answer the man's question with where I start.

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