How to make a wanted shape from a raw material?

[Demystifier]

I know almost nothing about engineering, so my question is very basic. Basically, assuming that I have a scheme for a prototype of something, how do make it from a raw material? If it is still not clear what do I ask, let me further simplify. Suppose that I want to make a well-shaped iron ball - how do I make it? How to shape the melted iron into a ball? Or into a nail? Or into a screw? Or into some other wanted shape?

I guess this type of problems has its own name, but I don't know what that name is? It would help me for further googling about such problems.

It would also help if you know youtube videos or something like that where the process of shaping can be better visualized.

 

[DrClaude]

I'm no engineer either, but to my knowledge for metal you can do forging, casting, or machining. See for instance http://www.sheldonbrown.com/dp-forging.html

There is nice presentation (not a video, but lots of nice images) here: https://prezi.com/clbg1br9sjf5/machining-vs-casting/

 

[256bits]

Try
https://en.wikipedia.org/wiki/Metal_fabrication
which gives you an outline of processes than can be done to make a part.

 

[CWatters]

Do you have access to TV programs like "How it's Made" (Discovery Channel). Some are on youtube..

https://www.youtube.com/channel/UCjHsPBHX1NNbIqTy4eXVTig

Nails and staples..


Steel forging..


Ball Bearings


Loads more available. For example to find out how Scissors are made just type in "How it's made Scissors" (without quotes) at the top of any youtube page..

 

[Demystifier]

I'm no engineer either, but to my knowledge for metal you can do forging, casting, or machining. See for instance http://www.sheldonbrown.com/dp-forging.html

There is nice presentation (not a video, but lots of nice images) here: https://prezi.com/clbg1br9sjf5/machining-vs-casting/

That's useful, but leads to a kind if infinite regress (or chicken-or-egg) problem.
For casting, I first need to make a mold. How do I make a mold in the first place?
Likewise, for machining I first need to make the machine. How do I make a machine if I don't already have one?

 

[Demystifier]

Do you have access to TV programs like "How it's Made" (Discovery Channel). Some are on youtube..

https://www.youtube.com/channel/UCjHsPBHX1NNbIqTy4eXVTig

Nails and staples..


Steel forging..


Ball Bearings


Loads more available. For example to find out how Scissors are made just type in "How it's made Scissors" (without quotes) at the top of any youtube page..

That was very useful, thanks!

 

[CWatters]

That's useful, but leads to a kind if infinite regress (or chicken-or-egg) problem.
For casting, I first need to make a mold. How do I make a mold in the first place?

Try "sand casting".

 

[SteamKing]

That's useful, but leads to a kind if infinite regress (or chicken-or-egg) problem.
For casting, I first need to make a mold. How do I make a mold in the first place?
Likewise, for machining I first need to make the machine. How do I make a machine if I don't already have one?

Fortunately, there are people who make machines and machine tools who sell these items to machinists and other skilled craftsmen who use them to make things.
No one mines iron ore, smelts it, turns it into iron, converts the iron to steel, shapes the steel into parts, assembles parts into a machine and makes stuff with it, all under one roof, and all from scratch. That's what a manufacturing economy is for. Different companies specializing in doing one part of the entire process.

 

[johnbbahm]

From what I understand cast iron is much weaker than forged.
I would think a machine shop could turn you a fairly good iron ball
from a chunk of scrap.

 

[SteamKing]

From what I understand cast iron is much weaker than forged.
I would think a machine shop could turn you a fairly good iron ball
from a chunk of scrap.

If you've got a lot of time on your hands, you can take a lump of iron and use a file.

That's what students who were apprentice machinists in Germany would do. They were each given a piece of steel and a file and told to make a cube measuring 150 mm on each edge. They were given something like 6 months to complete this project. After they were finished, the master machinist would inspect each apprentice's finished product and carefully measure the sides of the cube to ensure each measured 150 mm. The losers got voted out of the machine shop.

 

[tfr000]

If you've got a lot of time on your hands, you can take a lump of iron and use a file.

That's what students who were apprentice machinists in Germany would do. They were each given a piece of steel and a file and told to make a cube measuring 150 mm on each edge. They were given something like 6 months to complete this project. After they were finished, the master machinist would inspect each apprentice's finished product and carefully measure the sides of the cube to ensure each measured 150 mm. The losers got voted out of the machine shop.

Yup. The skill is called "flat filing".
About 100 years ago, one was required to have the skill to make machine parts by hand if no other means were available. One of the steps, for iron parts, was to first anneal the metal, that is, to heat treat it until it softened up some, to make it easier to work. Then one would harden it again with more heat, rapid cooling, and tempering.

 

[256bits]

Funny about the flat filing.
We had to make a letter opener out of brass using a file.
And a gauge for a set angle measurement out of steel by file.
Sandpaper to make it all nice and shiny.

I still have them as testament to my handywork.