My Cermark Tip

[Chris J Anderson]

I would just like to share this process that I use when cermarking Stainless Steel.
I'm not sure if this improves the marking on brass etc, but would be keen to find out.

Following a recent thread concerning marking of larger / thicker plates, all of the suggestions related to slowing down speed / increasing dpi etc.
All this does, is increase the heat at the metal surface where the laser strikes.

I had a client request a photo and text etched on to a large 1/4" thick SS plate supplied by him.
I was concerned about the etch not 'taking' to the metal properly...

so I preheated the plate after applying the cermark in a toaster oven.

The results were amazing. I have done several cermark jobs since and I always preheat after applying the cermark, and the difference is vey noticeable, it also ensures the cermark is completely dry before marking.

On one larger job I also used an air/heat gun to re-warm the plate during a pause in the job, again keeping the material hot.

I hope this info helps, it really is worth a try, and does make the result more consistent and reliable.

(My toaster oven is a $50 cheapie we use for surface mount pcb soldering as well).

Cheers to All.
Chris

[Dan Hintz]

I've often been tempted to run a few tests like this, to prove to myself one way or the other if preheating is a viable solution... but until then the engineer in me is not convinced.

The laser heats a very small area on the metal to an extreme temperature (hot enough to melt the glass frit in Cermark, so think about that for a minute), and this process happens in such a short period of time (<1ms) there can be very little transfer of that heat to the material outside of the focal point (at least during the melting process). Raising the temp of the substrate 50F via toaster oven, compared to the temperature differential at the focal point, is a very titchy change, comparatively speaking.

[Chris J Anderson]

Hey Dan,
Please give it a go, I would be keen to hear your thoughts after you try it on a heavy piece of steel.

I'm not an engineer, but I know it makes a difference at my end from my work so far.

Cheers Mate,
Chris.

[Mike Null]

I am inclined to agree with Dan. Additionally, most of my work would not permit handling and positioning after application. Most of my work is ok as is. When I've tried to hasten the drying time with a heat gun I've noticed some flaking.

I've had zero success with brass and aluminum but I will be doing some simple tests over the weekend which I hope will remedy that.