Everyone loves metal.
From name plates for corporate fat cats to monogrammed brass monocles for burning-man bums everyone has a use for some laser inked metal.
Put the two together and you can get some really cool results. You don't need a super powerful laser to mark on metal if you use a metal marking ink. In this Instructable I'll go over how to use Adobe Illustrator+RetnaEngrave+Cermark to make some cool designs on metal. This can be useful for all sorts of things, from making simple desk nameplates, to large signs, and all designs in between.
"I made it at TechShop"
Techshop is a great place for this project. They have all the necessary equipment and come readily equipped with eager admirers once you show them how awesome laser inked metal can be!
You can check out our other projects at smithallenstudio.com
Step 1: The Right Stuff
Unfortunatly it's not that cheap. There are a ton of instructions out there to other products that work for marking metals, and depending on the product and the base metal they may work okay. We tried a bunch of stuff on a bunch of different substrates and you really do get what you pay for. Our advice: get the right stuff.
So you will need:
A vector based drawing program (Adobe Illustrator, Rhino, AutoCAD, etc)
1 laser engraver (Full Spectrum Laser 36x24 used here)
1 can of Cermark (LMM-6000)
1 sheet of metal to be marked (6061 aluminum shown here) (McMasterCarr or equiv)
rubbing alcohol+paper towels
nitrile gloves (optional)
plywood to make jigs (optional)
Step 2: Prep the Artwork
Make your graphic or drawing in black on a white background.
You can go as heavy as you want, fills and thick lines work great. Thin lines work all the way down to about 0.25pt depending on the laser you are using. Explode your text to outlines to make sure it's read correctly. The laser will read both vectors and rasters so be mindful of what is filled and what is transparent.
Once you are done designing, measure your artwork, then measure your metal again, make sure everything will fit.
In order for Retina Engrave to respect the 0,0 position of artwork you must have something near to 0,0. So if your work doesn't contain both an x0 and a y0 you will need to trick the software. Do this by making a very time <0.5mm circle as close as you can to 0,0. This will force the driver to read the layout accurately.
Step 3: Prep the Metal
Cermark works well with almost all clean, unfinished metals. We've seen it work on polish, raw, brushed, and buffed textured metals. It seems to work best on metal cleaned with a scotch pad.
After removing any protective film on the metal clean it with water and a scrubber to remove an adhesive.
Scrub the sheet with a scotch pad to remove and residual imperfections and get a nice even finish.
After scrubbing allow the sheet to dry and wipe it down with paper towel and alcohol.
Try not to touch the parts of the metal to be engraved at this point, the oils in your fingers can mess up the inking.
You can put on gloves if you prefer.
If you have any extra metal or scrap you may want to spray it and mark it as well, it will come in handy if you are unsure of your laser settings.
Step 4: Spray the Metal
Make sure you are in a well ventilated area and have somewhere for the overspray to go.
Spray the metal with nice even strokes from about 8-10 inches away. The key is to make sure coverage is complete without over-covering. Too much cover can lead to weak marks.
Spray, wait for the paint to dry then tilt the metal to the light to see any inconsistent reflections, those are spots where the metal is still shining through.
When you are done the sheet should be a nice even matte tan on the side to be inked.
Let the ink dry and take it back to your laser.
Note: You CAN ink both sides of the plate at once, however the bottom side may get scratched by the laser bed. We'd recommend doing one side at a time.
Step 5: Set Up the Laser Job
Load the inked metal plate into the laser cutter. Focus the beam without scratching the sprayed ink coat.
Move the laser to be zeroed at the upper left corner of your material.
Make sure your edges are straight and parallel to the axes of the laser. If you're doing multiples or duplicated this is a good time to make a laser cut guide.
Once you're happy with the sheets positioning open up your artwork file and print it to your printer driver.
In this process I'm printing from Illustrator to the Full Spectrum Retina Engrave Driver. I have to open Retina Engrave separately in order for it to work.
Your vector lines should come into driver software depending on your artwork as Rasters or Vectors. Both work with this process and we will be using Rasters.
Go to the Raster Tab in Retina Engrave and you will see your artwork.
CHECK YOUR WORK AND YOUR SPACING!!!
DOUBLE CHECK IT!
If it looks like the work may have moved over it probably has, check that your layout dot from step 2 is large enough to be recognized.
Time to start the laser show!
Step 6: LASER Time!
For this demo I'm using a 120Watt Laser.
I'm graving at 90%speed and 60%power.
That is a very high power setting and is probably more than enough. The ink works a lot better when you overdo it than under.
If you have a piece of scrap metal that you sprayed, test the power and speed settings before moving on to the main event. To test engrave a small test graphic on the metal then wash it off to test the hold. If there is no hold then use more power/lower speed.
When in doubt blast it out!
Once your tests are completed position your sheet at the home location (if it isn't already).
Double check everything.
Click Play/Go/Start on your driver software.
The laser should respond shortly and start your work.
Step 7: Laser Tending
Watch it's mesmerizing glow.
It will trace out your artwork.
Wait for it to complete the job, stop and return to home.
Step 8: Post Processing
Remove the laser inked sheet carefully without damaging the laser cutter.
Take the sheet to the sink and wash the sprayed on film away.
Like magic the parts that the laser hit will be a dark black while the rest is raw metal!
You can lightly scrub any stubborn paint away with a scotch pad, the set ink should stay.
The marks should be durable and resist scratching.
Congratulations! You have just learned how to laser mark on metal!