Re: [CAD_CAM_EDM_DRO] Was Laser Engraving. . .question regarding reflectivity issue

Peter Stempel wrote:

>This is a how did they do that. . .
>
>I am curious about the reflection issue. In the mid 90s I had many parts
>cut from stainless sheet that had been prestamped with a pattern--it was
>somewhat reflective, and was about 18 gauge. I mention the stamping,
>because not only was it reflective in its finish, it was variably shaped.
>We only re-finished the edges after cutting. Although a few cutters sent
>me away, the one I used had absolutely no problem, and claimed they could
>even cut mirror finished stainless. This was probably about 1996 or 97 at
>the latest. Wondering how they got around the reflection issue. Is
>Aluminum more reflective than stainless in the required wavelengths?
>

it may be, but the real difference is the thermal conductivity.
Aluminum is a
GREAT thermal conductor, and also has a very high specific heat, unusual
for a
light metal. It takes about twice as much heat to raise aluminum a degree
C than for copper or Iron (Don't have a number for steel). The thermal
conductivity is about 3 times that of iron, and almost as high as copper.
So, this is the worst combination - high specific heat AND high thermal
conductivity.

Jon