Using Precision Measurement Tools in Toolmaking
It is understandable that the average person knows very little about precision measurement tools.
After all, how many people use things like dial indicators, precision micrometers, pin gages, coordinate measuring machines, granite surface plates, gage blocks, and optical comparators? These are all basic tools of the trade for the skilled craftsmen who work in the injection mold making, tool and die making and precision aerospace machining trades.
Without these tools, it would be completely impossible to manufacture the things we all use and enjoy every single day.
These measuring tools enable precision inspection in the range of .
0002 in.
/.
005 mm..
This may not mean much until you put it into perspective.
Take, for example, a cigarette paper, which is typically .
0008 in.
thick.
If you were to split it in the thickness, you would have 2 pieces of .
0004 in.
thick paper.
Split one of those again and you have a paper that is .
0002 in thickness.
This is a typical tolerance in all of the precision machining trades, including micro precision andmedical precision machining.
The human finger is actually able to feel the difference in two adjacent surfaces that vary by .
0002, at least with some practice.
You can do the same splitting process with a human hair to get an idea of what a toolmaker deals with regularly.
The hair is usually about .
004 in.
in diameter.
You would need to keep splitting it 4 times to arrive at approximately the same tiny dimension.
With proper training, technique and tooling it is not extremely difficult to hold these tolerances.
It does take time, however.
You cannot rush through the process, or you will end up with scrap.
One of the biggest hindrances is the heating and subsequent cooling of the workpiece.
This causes expansion and contraction of the metal, which, of course, affects the size of the part.
It is remarkable just how much the size can change overnight! Some of the machines that are used to produce these parts and tools are:
For example: your computer monitor, keyboard, mouse, pen, lighting, desk, chair, fire extinguisher, smoke alarm, etc.
These are typical items we all use on a daily basis, yet rarely, if ever, consider what it takes to produce them.
In our society, manufacturing is often looked down upon, in comparison with the so-called professional jobs.
This is unfortunate because some of the most highly skilled and talented people to be found work in manufacturing.
The typical toolmaker has gone to a technical school and served an apprenticeship for 4 years.
On top of this, there are usually a number of special classes and training programs that they participate in.
So, the next time you use your cell phone, think of what it took to produce such a useful thing!
After all, how many people use things like dial indicators, precision micrometers, pin gages, coordinate measuring machines, granite surface plates, gage blocks, and optical comparators? These are all basic tools of the trade for the skilled craftsmen who work in the injection mold making, tool and die making and precision aerospace machining trades.
Without these tools, it would be completely impossible to manufacture the things we all use and enjoy every single day.
These measuring tools enable precision inspection in the range of .
0002 in.
/.
005 mm..
This may not mean much until you put it into perspective.
Take, for example, a cigarette paper, which is typically .
0008 in.
thick.
If you were to split it in the thickness, you would have 2 pieces of .
0004 in.
thick paper.
Split one of those again and you have a paper that is .
0002 in thickness.
This is a typical tolerance in all of the precision machining trades, including micro precision andmedical precision machining.
The human finger is actually able to feel the difference in two adjacent surfaces that vary by .
0002, at least with some practice.
You can do the same splitting process with a human hair to get an idea of what a toolmaker deals with regularly.
The hair is usually about .
004 in.
in diameter.
You would need to keep splitting it 4 times to arrive at approximately the same tiny dimension.
With proper training, technique and tooling it is not extremely difficult to hold these tolerances.
It does take time, however.
You cannot rush through the process, or you will end up with scrap.
One of the biggest hindrances is the heating and subsequent cooling of the workpiece.
This causes expansion and contraction of the metal, which, of course, affects the size of the part.
It is remarkable just how much the size can change overnight! Some of the machines that are used to produce these parts and tools are:
- CNC machining centers
- CNC lathes
- EDM machines
- WEDM a.
k.
a.
Wire EDM - Surface grinders
- Honing machines
- Manual lathes
- Cylindrical grinders
For example: your computer monitor, keyboard, mouse, pen, lighting, desk, chair, fire extinguisher, smoke alarm, etc.
These are typical items we all use on a daily basis, yet rarely, if ever, consider what it takes to produce them.
In our society, manufacturing is often looked down upon, in comparison with the so-called professional jobs.
This is unfortunate because some of the most highly skilled and talented people to be found work in manufacturing.
The typical toolmaker has gone to a technical school and served an apprenticeship for 4 years.
On top of this, there are usually a number of special classes and training programs that they participate in.
So, the next time you use your cell phone, think of what it took to produce such a useful thing!
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