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brian fithian
12-26-2015, 1:12 PM
Have done only a handful of SS jobs and got good results in the past. I am using Thermark engraving on SS tags that are only 1/64" thick. Using a 40W laser with settings of 40S/100P. Engraving looks good but the tags are bowing pretty good. Only have about 8 samples to work with to get it right. Any help on settings before I go through these very small samples.

Mark Sipes
12-26-2015, 3:21 PM
Bowing is a sign of toooo much heat. Speed up or reduce power.... 2 sides to samples?? I would cut power by 50% and see what the effect is. If material is not bowing and not covering well increase % of power. I find sometimes hitting it twice with a second light coat...same settings gives me great results.

Tony Lenkic
12-26-2015, 6:01 PM
1/64" is way to thin to laser with thermark so bowing is what I would expect. In order to get good mark you need high power/slow speed or it otherwise etching will not stick.
Can you get heavier gauge tags (0.35-0.40 minimum).

Scott Shepherd
12-26-2015, 6:42 PM
1/64" is way to thin to laser with thermark so bowing is what I would expect. In order to get good mark you need high power/slow speed or it otherwise etching will not stick.
Can you get heavier gauge tags (0.35-0.40 minimum).

Totally agree with Tony. We did some tags for a customer that were log dog tag size but numbered for hanging on pipes in a facility. They had to be stainless steel and they were very thin. We marked them and they were happy, but they did bow and there's nothing you can do to stop it when it's that thin.

Neville Stewart
12-27-2015, 7:33 AM
Spray, freeze, lase! Maybe :)

Gary Hair
12-27-2015, 10:54 AM
Only have about 8 samples to work with to get it right. Any help on settings before I go through these very small samples.

Same advice I give everyone for Cermark - run a power grid.

Dan Hintz
12-27-2015, 12:35 PM
If you know the thickness of the samples, grab some similar gauge stainless from your local McMasters (et. al.). No need to waste the samples.

But I'm with the others... you have your work cut out for you with such thin pieces. About the only way you can expect to keep it (somewhat) flat is to make up a fixture that grabs onto the edges... it'll still bow, but possibly a bit less.

Kev Williams
12-27-2015, 1:40 PM
The only SS I've engraved that thin are military dog tags. Because they have rolled edges, their very rigid, and resist warping. However, even when hitting them with not enough heat to fuse Cermark to the surface, it's still enough heat that it actually distorts the metal, you can read what you engraved by the 'dents' on the opposite side...

There's a fine line between enough heat to adequately fuse Cermark to stainless permanently and not- My LS900 for example, I get iffy results at 20 speed, so I never run it lower than 18 speed, and usually 15 speed or lower. I recently ran a test at 25 speed, and it looked great, up until I took a try terry cloth towel to it, and wiped half the black off.

FWIW, I tested my speeds with a stopwatch (as best I could), my 25% speed equates to 18.5" per second, 18% equals 13.3" per second, and 15% speed equals 11.2" per second.
My machine's full speed is 72" per second, and interstingly enough, my numbers are very close to 'actual' numbers: 72x 25%=18", x18%=13.96, and x15%=10.8...

All I know is, Cermark fuses nicely at 18 speed, not so well at 25 speed. And when Cermark is fusing well, SS can warp due to heat buildup...

Russel Nidel
01-03-2016, 2:41 PM
I've been surprised by the wide range of power I need for Cermark LMM-6000 (rattlecan) on stainless. Y'all probably know it already, but I'm just figuring out how the thickness impacts the power requirement.

On the rolled-edge dog tags, I had to back off power to 70% Pwr / 100% Speed (60W ULS) or it would over-burn, extend the edges, and brown out the Cermark. At the reduced power, it had much less 'embossing' visible from the backside, and good black results.

The same coating on a flask needed 100% power 60% speed for a good black mark that wouldn't scrub off.

A stainless thermos? 100/100, somewhere in between the other two.

Making test grids seems to be the only way to really dial in the maximum blackness for each substrate. Keep good notes. :)

brian fithian
01-05-2016, 8:48 PM
thanks for all the help fellas... I ended up finding the "sweet spot" and they turned out pretty good..

Bryan Spiegel
01-06-2016, 1:37 AM
Would placing them on a larger metal flat surface help? So the heat does its job but is moved away quickly? Maybe on the back of a discarded PC CPU heatsink.