Darkly Labs Community

Focus power! or: how I learned to live with a cleaner lens

Noting on someone else’s post the relatively low pass count for cutting 3mm plywood, I knew there was a problem with my laser. With sufficient afterthought, I realized that I was previously cutting through with the same number of passes, but recently had to increment that number appreciably. Rather than hijack that thread, here’s my contribution.

I knew that I had a good focus, despite suggestions to the contrary. I had spent three hours dialing in that tiny dot and the resultant narrow-width lines, one focus ring notch at a time, with a 50x magnifier. You know you have it dialed in when the line is 0.05 mm wide, right?

Even better, I did not have to tamper with my focus to remove the laser module, despite the instructions. I’m not sure why the instructions suggest to remove the lens, unless it is to install in the replacement module. No replacement for me, no lens removal for me.

Flipping the laser module over so the lens pointed directly at my eyes, I was instantly blinded. No, not really. After all, it was completely disconnected from the carriage. However, I was able to detect an obvious fogging of the lens, in a rather large rectangle shape. Air from a compressed air can did nothing. I’m hopeful that the 70 percent alcohol I used with a lint-free wipe did not cause damage to the glass lens, but it did remove the fogged rectangle. A bit more canned air, and the lens looked loverly.

Back into the assembly and my laser sliced nicely through with the expected five passes.

I have been using honeycomb mesh under my work pieces since about day one, learning from posts here that it improves cutting. In this case, the test slice was made so the last piece fell away from the honeycomb, in a manner similar to cutting a board with a circular saw.

Very satisfying!

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Hi

I needed to give my whole machine a clean and seeing your post I did the same - I have been tempted to do so for a while. Very definite improvement in performance, I was surprised by the amount of black soot that had built up on the top lens of the assembly. Performance is now better than I’ve ever had it and finally aligned with what others have been seeing (rather than 10-15% behind)

Agree, very satisfying!

 

How long do you all think you ran your Emblaser before the lens needed cleaning? I’ve been putting it off because my fingers like to loose small parts :(.

 

Thanks

Mark

I probably cut mostly 3 mm plywood for about 30 hours or so before I had to clean it. The bigger problem is that instead of realizing the root cause, I kept slowing the rate of travel and increasing the number of passes. If you have a consistent reference that changes, it’s a good indication for the need to clean.

With the long-gone death of VCRs, I doubt I would easily find lint free swabs, but my future cleanings will not involve disassembly. I should be able to slide the laser module to the top of travel, apply the alcohol to the lint free cleaning material and rotate it within the nozzle assembly. I should be able to bend the air tube from the compressed air can to dry the lens as easily.

The product I’m using is a genuine Kleenex product named Kleenex Hand Towels, a non-abrasive paper towel substitute. I found it cleans lexan and acrylic without the scratches that paper towels create. A small portion torn from a corner is enough to perform the cleaning task.

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Thanks for the reply Fred. I appreciate it.

Mark