RE: [CAD_CAM_EDM_DRO] Re: Keling - Laser Cutting/Engraving Machine

> Returning to practicalities for the sort of laser cutting system we are

discussing

> here, I have a 50watt CO2 laser cutting system fitted with a Synrad laser.

The

> beam diameter at the lens (from memory) is around 8mm (I have a collimator
> fitted the output of the laser). I can use either 100mm or 50mm focal

length

> lenses. I almost never use the 50mm lenses, the increased depth of focus

of the

> 100mm lens greatly outweighs the advantage of the smaller spot diameter.

With

> the 100mm lens the cut kerf widths in 6mm MDF are typically in the 0.1 to
> 0.15mm range. I can't remember what they are with the 50mm lens, but they
> are not significantly smaller.

The kerf on a 50mm lens is about the same - 0.1 - 0.15mm. The difference is
you are more likely to get a slanted edge on material with the 50mm lens
(short depth of cut) than the 100mm one. 3mm stuff comes out ok, thicker
material has a problem. You can do two cuts and raise the table between
them to compensate.

I've got a 20mm lens, and it is very sensitive to getting the material at
the right height. It's depth of cut must be tiny (fair enough, it is for
engraving after all).

In the end, who cares what the kerf is? So long as it's consistent and you
know what it is, you can work to that. (For the imperial crowd we're
talking about 4-5 thou - many machinist would be happy with that.)

I wonder if the audiophile salesmen have moved onto lasers - "our CO2 beams
are MUCH warmer than theirs..."

Tony