Terminology of Metallurgy?

[kin0kin]

hey guys, please help a metal n00b understand some of the terminology.

1) Is the hole within a hole at the jack called Cavity through-hole?
2) What is a counter sink?

thanks.

 

[dgardner]

The hole for the jack is called a counterbore.

 

[chillysalsa]

This is machinist talk, it is not metallurgy related.

A counter-sink is using tapered screws that will be flush with the surface.

 

[DaKi][er]

Quote:

Originally Posted by dgardner The hole for the jack is called a counterbore.

And you can think of countersinking as the same as a counterbore but instead of 90 degree cut, it is on a 45 and allows for a screw heat to sit flush with the surface it is attaching

http://www.diydoctor.org.uk/projects/Countersink.htm

And metallurgy is more the science and chemistry behind metals, about their internal atomic structure and properties

 

[kin0kin]

cool. What do I call it if I want the counterbore's edge to have 45degrees cut like countersink? counter sink bore?

 

[nikongod]

Quote:

Originally Posted by kin0kin cool. What do I call it if I want the counterbore's edge to have 45degrees cut like countersink? counter sink bore?

chambfered. someone else should correct my spelling...

 

[tangent]

Quote:

Originally Posted by DaKi][er And you can think of countersinking as the same as a counterbore but instead of 90 degree cut, it is on a 45

First, machine screw head angles are measured in terms of the angle the sides would make if they came to a point. So, if the screw needs a countersink with a 45 degree slope relative to the "flat" surface, you'd say the screw had a 90 degree head angle.

With that out of the way: screws with a 90 degree head angle are available, but they're the third most popular type. Far and away the most common are 82 degree. 100 degree is also popular, especially in screws meant for soft materials, since the load is distributed over a wider area. You probably can't even find 90's at your local hardware store.

Quote:

Originally Posted by nikongod chambfered

Drop the 'b'.

 

[DaKi][er]

Quote:

Originally Posted by tangent With that out of the way: screws with a 90 degree head angle are available, but they're the third most popular type. Far and away the most common are 82 degree. 100 degree is also popular, especially in screws meant for soft materials, since the load is distributed over a wider area. You probably can't even find 90's at your local hardware store.

Close enough, half the time i just use a big drill bit to countersink holes and that gives 120 degrees there for your standard drills, but that is mostly working with hardwood, i dont do that much metal work here