Can anybody help k40 takes 7 or 8 passes to cut 3mm mdf I’m having issues with laser strength
Depends if it’s a new problem or has always been that way. This is usually a problem with alignment or focus. Check those first before worrying about hardware (like a failing tube). Also check mirrors and lens for cleanliness.
Also, what kind of speed/power are you using? I used about 6mA, 20mm/s & can cut through 3mm ply in 2 passes. Can’t recall for MDF, but it was similar.
If it by bad alignment try this guide https://plus.google.com/+ArielYahni/posts/ho5JAUMgTmE
@Yuusuf_Sallahuddin_Y , with air assist, I do 8mA @ 10mm/s for a single pass. Less power if I’m cutting something like Aspen as there’s no glue to cut through.
Thanks guys I was right up to 20mA and aroun 8mm/s I tried maybe 6 passes and still didn’t go fully through I realigned today and cleaned lenses but still no luck I’m going crazy
Is the lens right side up and focus correct?
I try that Jim not sure how to focus do you mean align the mirrors
20mA is too high for a K40, you’re over driving it and shortening its lifespan. When you look at the lens while it’s in the screw ring, you should be able to see your face reflected back. Or, if you can tell the difference, the curved side goes up, flat down. As for focus, by default, all these machines come with a 50.8mm focal length, meaning the bottom of the lens to the material should be that distance.
What @Ashley_M_Kirchner_No said - make sure the bump is up for the lens and then the distance between the bottom of the lens to the top of the material is 50.8mm. You can get a bit more performance by making it 49.3mm so you’re focused midway through the 3mm material but it’s not really necessary to get good cuts with lower power than you’re using now.
@Ashley_M_Kirchner_No thanks for your help and for the advice I really didn’t want to use the k40 at 20mA but it was the only way to get the cut done il adjust everything tomorrow hopefully that works
Another test you can do is called the ramp test. Put a scrap piece of board at an angle, whether front to back, or left to right, doesn’t matter. Then run a cut mark in the same direction. You’ll notice it starting with a wide burn, gradually get thinner, then go wide again. Where the line is thinnest, that’s your focal plane. This YouTube video shows one method. Notice how the line gets thinner towards the end. https://www.youtube.com/watch?v=o4ccNRMTpGQ Where the line is thinnest, that’s the focal plane.
It’s also worth checking whether both the bed itself is level, as well as the rails being level in relation to the bed. I used to have a hard time cutting things in the lower right corner till I paid closer attention and noticed that the bed was lower in that corner, causing the laser beam to be out of focus and not cutting all the way through. Small details make a huge difference.
Thanks a million guys that worked brilliant I levelled everything out and
raised the bed thanks for the tips on the focus point it’s working better
than ever that’s the end of two of me going crazy
Awesome! Glad you sorted it out.