Looking for help on understanding engraving metal. Specifically about paint.
Are people saying they painted their piece and then put it in the machine to be lasered? What about fumes and fire? I don’t want to explode my GF.
If the paint goes on BF, can I use acrylic craft paint or does it have to be a durable spray paint or dry lube spray and why?
Just learned about a product “CerMark” that is a paste or spray “paint” you apply to the surface and it bonds to the material (they have versions for metals & now glass & tile) where the laser hits it.
Regular paints can never do this–it requires special chemistry not only to acheive the reaction (and durable finish) but also to minimize and toxic or even flammable by products.
But the GF isn’t rated to etch most metals. (Other threads about this).
But if you do etch anything, you can apply a paint or dye into the etched areas (easier to do before you remove the masking) and pending the base material and paint/dye, it may be quite durable! E.g. for wood, acrylic paint works nicely. For acrylic, I’ve had great results using leather edge dye.
A few questions in there
There are a couple of basic approaches people are using to mark metal (a 40W CO2 laser can’t really etch anything except the anodization of aluminum).
The first is a material like Cermark or Thermark. You spray a coating on the metal and then laser (use an engrave setting). This fuses the material to the metal very similar to the way laser printers fuse toner to a piece of paper. This creates a very tough and mostly permanent black (or other colors with Cermark) engraving on the metal. It looks like all those steel water tumblers with various graphics you can buy in a store. The spray coating that was not lasered washes off.
Dry Moly Lube is an alternative to the products above. It’s about $11 vs $100 a can and is available in your local autoparts store. It doesn’t leave quite as black a design as Cer/Thermark but it is certainly good for many applications. You’d have to decide for yourself though if it fits what you’re trying to do.
The other major approach to getting a lasered design on a metal object is to use paint. You can paint first and everything you engrave will expose the metal. Or you can mask the metal with a vinyl transfer tape (it’s not really vinyl btw so it’s safe in the laser) and after the design lasers off the masking, you paint the piece, let it dry and then peel off the remaining masking.
Either approach is safe for your laser. Acrylics or other paints can be used in either case. It would be a rare paint that you couldn’t laser - certainly not any of the ones you’ll find in craft and home stores. Those should all be fine. They will tend not to be as tough and long lasting as Cer/Thermark but may well be all you need - you could experiment with some paints to see what their wear characteristics are. For art pieces paint would be fine as there’s not a lot of handling. On the other hand, a keychain might expose the paint to so much wear that it abrades off over time.
So your decision is really around what you would like the result to be - marking on bare metal (Cer/Thermark or masking then painting) or metal showing through a color layer (paint before lasering).
I am relatively new to this (I have engraved some wood so far) and would like to try engraving a metal tumbler. I have read the posts about the three methods to use, but one thing I do not see is the engraving settings either recommended or suggested. On that note has anyone “published” or added to a document with their settings for their projects?
I have the Pro with the 45 Watt laser, so I imagine the power setting would be less than for the 40 Watt laser.
It was also stated that the 40 Watt laser could not engrave metal hence the discussion of the three methods. Can the 45 Watt engrave metal or is it also not powerful enough or is laser-to-metal engraving just not a good idea in general?
What about anodized metal?
Any power setting other than “Full” is the same on all GF models so project settings are directly compatible. If the power setting is Full and the project was using a Basic or Plus, then you’d adjust by increasing the speeds since your Full power is more than theirs.
CO2 lasers (at least in the relatively affordable class) aren’t powerful enough to actually engrave metal. They can mark the metal using something like Cermark or Moly lube that the laser will fuse to the metal.
They can also burn through a top level coating like paint or powder coat revealing the underlying metal.
Aluminum is usually anodized and you can burn that (it’s actually removing the color) and reveal the underlying aluminum color which is usually silver.
you have a bigger issue with the tumbler than even whether the GF can mark it. the maximum material height in the GF is 2". that would be a very small tumbler. additionally, there’s no rotary attachment, so trying to engrave more than a small portion would be very difficult.
some people have gotten around some of these limitations, but often that means modifying the machine in a way that voids the warranty (and often means additional safety measures are needed).
Yes, the 2-inch limit is a consideration and I have no intention of altering this machine at least until the warranty is up!
One of the ideas I had was to buy aluminum plates, engrave them and then fasten them to the tumbler. Not as integrated as I would prefer but more easily worked.
Hi, I’ve not tried it myself, but my understanding is it should work OK–the laser is etching off the anodized layer. Likely you can find topics that provide settings & tips!