I have started putting a new tube in my K40,

I have started putting a new tube in my K40, how far should the laser be from the 1st mirror? I’m guessing as my new tube is larger 66w!

Isn’t that tube too long?

I added an extension to add for the longer tube from light object plenty of room!

I can’t think of a reason it really matters. The closer the better to decrease angular sensitivity but not so close as to make adjustments and targets a challenge.

tube from light objects also?

The distance doesn’t matter, but in the future take pictures before you remove old one.

Also are the mounts big enough? The diameter of a 60 watt tube is generally larger. My true 40 Watt replacement required changing the mounts out.


No purchased from another firm , twenty dollars difference between 40 w and the 66w!

Had to replace tube, broke due to cold

@Jerry_Martin What length is your tube?

@Matt_Staum 40 inches