[ATM] How dark is dark

[Fabio Pettinati]

Are you using a 60-degree bit for the V thread or a custom angle? Any  
rule of thumb regarding ideal thread pitch versus thread diameter?  
Sharp threads are more fragile than threads with a crest; how sharp  
are your light absorbing threads?

Fabio
San Jose, CA

On Sep 27, 2006, at 6:02 AM, Don Clement wrote:

> I also thread the internal black anodized surfaces with a sharp "V"
> thread for the same reason. The sharp "V" threads behave as a  
> helical stack
> of razor edges to trap and absorb light. The sharp "V" threaded  
> internal
> surface appears much blacker (less reflected light) than a surface  
> that is
> smooth black anodized.