I ever wanted to know how much beam power my K40 realy has. So I bought a Laser Power Meter from Cloudray:
There is not enough space to place the meter between the tube and the first mirror, so I measured after the first mirror. At 18mA the meter shows around 28W. I expected to be less than the advertized 40W, but 28W is a bit low.
Does anyone have such measurements for his K40?