Hello everyone! I recently acquired a 130 watt laser machine and wanted to know if it is possible to change the 20mm / 63.5FL lens for a 20mm / 38.1FL lens. The idea is to get a better definition in engraving.
Hi and welcome to the forum.
Shouldn’t be an issue as long as you get a lens that is appropriate for that power range or at least keep the power low.
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Hello Ned, I was wondering if the lens tube would have to be changed too, since the one I have in the machine is for a 63.5FL. I have not been able to see one for sale.
Yeah there is that also. Your tube lens or air assist tube would need to be short enough to accommodate the shorter FL.
They make laser heads with adjustable tubes like these.
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Thanks, that should do the trick!
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I get the best engraving with this compound lens…
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Thanks for the info! That is a pretty interesting nozzle and video. How many watts is your CO2 laser?
It’s a ‘China Blue’ 50 watt. It’s had some modifications to it, but it’s the standard general type co2.
This is the compound lenses mounted with the PiBurn rotary for mugs.
I would love to have a bigger machine. I do mostly engraving and it’s a minimum power settings. So at 10%, for example, I put out about 4.5 watts. If the lowest power you can ‘lase’ is 10% you cannot get the detail with 18 watts that I can get with 4.5 watts. One of the tradeoffs I was unaware of when I started this stuff…
Of course, I can’t lase my neighbors tree off either… 
Have fun…
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You’re totally right! My K40 gives me a better finish when engraving on rubber or acrylic. I´m gonna have to do a lot of testing with different combinations of lenses and power to see if I can get something decent. I need this new machine to start producing money asap.
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