When the lens cracks, the only thing you can do is open the lid to your trash can.

When the lens cracks, the only thing you can do is open the lid to your trash can.

I do not want to sound like your mother, but keeping your laser clean not only improves your productivity, it also saves you money. More specifically, I am talking about the cleanliness of your laser optics. To be honest, I am extremely guilty of making those expensive mistakes where we forgot to periodically check the laser optics and then were forced to replace the expensive laser optics.

Depending on the type of material that you are engraving and the quality of your exhaust system, you may have to clean the optics multiple times a day! If you decide to ignore the problem, you will be quickly reminded of the $200 mistake. In addition, if you do not carry additional optics, you will likely have to pay air freight for replacements.

So, the basic question is what should you clean with, and what technique should you use? First, when you are laser engraving items, the resulting smoke carries oils and other contaminants which coat themselves onto your optics. This is yet another reminder that your exhaust system should be strong enough to quickly remove the smoke from your laser cabinet. Check with your laser manufacturer on exhaust specifications.

Running your laser with dirty optics is like looking through a dirty window. You can still see something, but it is difficult to do so. In the same vein, your laser will still work with dirty optics, but instead of the laser beam being focused and directing all its energy on your product, some of the laser energy is held back by the dirty coating. If you let this happen for too long, the laser may melt the contaminant on the lens, or the lens may even crack. When the lens cracks, the only thing you can do is open the lid to your trash can.

While cleaning laser optics is considered very basic maintenance, it is often ignored. But what should you use to clean the laser optics? Window cleaners such as Windex should never be used, as they contain chemicals which will eat away at the specialized coating and will essentially deteriorate your optics. An alcohol-based cleaning solution which evaporates quickly and does not leave any residue is highly recommended. All laser manufacturers sell their own version of laser cleaning solution. Third-party companies also sell their own version of cleaning solution which is laser friendly.

We often use a high-grade, also known as scientific-grade acetone. Let me repeat this, because this is essential. If you want to use acetone as your primary cleaning solution, you must, and I mean must use a high-grade, scientific-grade solution. You will not find this type of acetone from your local hardware store, and likely you would have to contact your local industrial chemical supplier. Because of the ability of the scientific-grade acetone to quickly evaporate, make sure you reaffix the cap as quickly as possible after using. Otherwise, you will be wondering where all the cleaning solution went.

One of the leading suppliers to laser engravers told me that he has seen everything when it comes to laser maintenance and cleaning. He has even heard of people using Everclear, a distilled grain liquor. Everclear liquor, which has a very high concentrated composition of alcohol, does work in theory. I am not sure I would highly recommend using Everclear as a cleaning agent.

Spray off any debris from the optics using compressed air. Always wet the optics and the tissue when you are cleaning. Using light pressure, use a laser tissue or special q-tip to remove grime from the lens.

The next step is the actual technique of cleaning the lens using the proper cleaning solution. Once again, let’s start with the no-no’s. Do not use paper towel, as the rough fibers in paper towel will actually damage your optics and create minute scratches on your lens. You may not be able to see the scratches, but once you magnify you can understand why the laser beam does not freely pass through and hence reduce your laser efficiency. You should never use a rag or cloth which could contain particles which could also scratch your lens. Another product which I would not recommend using is the traditional q-tips. Once again you run the risk of scratching the lens with q-tips.

I would recommend using proper laser optic tissues when cleaning the lens. These are inexpensive and available from numerous sources including laser manufacturers. These are very handy in those tight spots.

Depending on your laser, you may have to remove the lens and the accompanying holder to clean the lens. After this, you simply spray off any debris from the optics using compressed air. Second, you need to apply the cleaning solution to the optics by spraying it on. Last, using light pressure, use the laser tissue or special q-tip to remove the grime from the lens. Ensure that you clean in one direction and do not re-use the same spot of the tissue or q-tip. It goes without saying that you should never wipe the laser optics with a dry tissue or specialized q-tip. Always wet the optics and the tissue when you are cleaning.

This article predominantly is discussing the importance of cleaning your focal lens, but the same principle applies to all your laser optics, including mirrors. You can operate the laser with a dirty mirror, but only for so long. As I mentioned previously, the grime will be fused to the mirror and eventually disable it. A supplier shared a great little story with me. He mentioned that a client of his was in a pinch, as one of his mirrors had cracked and hence the laser was inoperable.

Many of us have been in tight situations like this where we are in the final hour and Mr. Murphy and his law comes into play. The laser project was due the following morning, and the operator became rather ingenious. He took part of a stainless steel cooking spatula and buffed it to a mirror finish. He then cut part of it out and mounted it on top of the dead mirror. Apparently, it worked and he was able to get the project completed. Wow. This reminds of the 1980’show “MacGyver”, where the lead actor would undoubtedly create some sort of device with chewing gum, shoelaces and his trusted Swiss army knife.

It goes without saying that you have invested a lot of time, money and attention to your laser. Why not ensure that your laser operates as efficiently as possible by keeping the optics clean? Trust me; your mother and your banker would be happy with you!

On a different note, I would like to invite the readers of A&E to share their insights with their fellow laser engravers. Basically, I would like to hear about the unusual, interesting and weird items you have laser engraved. I would like to do an article describing what you did and how you did it. Please forward your details to rkorbyl@columbia-awards.com. If you have some photos, please send them along also!