Engraving Bronze Urn

[Terry Wade]

Hey guy's I have a customer that wants me to engrave the death date on a bronze urn. I stopped by Hobby Lobby and found a small bronze sheet to test on and I'm not getting the results I was expecting. I have a 50 watt fiber laser and have tried various settings for brass, aluminum, stainless and still haven't been able to get anything acceptable. Does anyone have any experience with bronze?

Thank You,

Terry Wade

[Gary Hair]

Do you want to mark it or engrave it? My settings to mark were low power (30%), high speed (1,500), and high frequency (60). To engrave I used 100% power, 250 speed, 30 Frequency. My laser is 30 watts so adjust to suit your 50.

edit: the bronze you got at HL is not likely the same as the urn so your results will definitely be different between the two. Try testing on the inside of the lid.

[Kev Williams]

There's bronze, and then there's bronze... Chances are the urn will be a much different bronze than the sheet you have.

I've been inundated with brass tag and name plate orders lately, this pic,
the big plate is engravers brass, the small plate is just 'plain' brass, some tags I've
had for years that I'm testing the fiber on...
426945
note the leaded engravers brass I can get near jet black (it's actually really really really dark brown ;) ),
but the 'hard' brass, not so much. The darker 'TEXT' I got by using a slow, tight spaced wobble, pretty slow
but will be do-able for brass wire tags...

To get the leaded to go black, using my ebay1 30 watt with a 150 lens, I run
just a single 30° hatch pass at .002" spacing (yes, 2 zeros), 100% power, 600 speed and 80kz.
But, these same plates, I started a few tonight on my ebay2 machine, identical to ebay 1 EXCEPT
it has a 220 lens, which tempers the beam to the point that all new settings are needed;
cross hatch instead of a single pass, .003 hatch spacing, 100% power, 800 speed and 38kz.
I can get this machine to do it in a single pass, but it's slower than a double pass at these settings, and not as consistent...

With your machine, try a .003 single hatch, 100 power, 800 speed and 120kz on the piece of bronze.
If no go, make 20kz adjustments downward, I've found brass and copper to be very frequency dependent...

[Terry Wade]

I want to thank you guy's for the suggestions, the lady called and had something come up so we have to reschedule. But when I tried the settings on the bronze test sheet I was able to get what I was looking for when the frequency got to 80kz. So I feel like a have a good place to start when I get the actual piece here. I was quite amazed how much just changing the frequency has on the end result, still learning about this fiber laser and you guy's are great teachers, again thank you!!!

Terry Wade

[Kev Williams]

Be aware that sometimes what looks great with copper/bronze type materials, even SS sometimes, will wash away with a little cleaning, sometimes the ash goes very dark but will wash out. You've likely done this but my first time I learned the hard way! ;)

[Chris DeGerolamo]

Be aware that sometimes what looks great with copper/bronze type materials, even SS sometimes, will wash away with a little cleaning, sometimes the ash goes very dark but will wash out. You've likely done this but my first time I learned the hard way! ;)

Really fun on firearms, like Henry Goldenboys :/ When in doubt, a qtip with simple green or WD40 can help determine whether it's permanent or not....kinda hard to line up items after the fact.

[John Lifer]

Now that was a GOOD tip Chris. I've not had issue with any coming off, (done 3 or 4 Henry's) but I I totally agree that brass, bronze and similar materials can be a pain.

[Kev Williams]

If your red light is aligned dead-on to your engraving, it's actually pretty easy to line back up to re-engrave-- a 2x or 3x loupe and some patience helps! ;)