Black Granite, Power and speed..

[Jeffrey Dewing]

I have a brand new Trotec Speedy 300, 80 watt.I'm getting great results engraving photos on black marble! I'm using 30 power and 100 speed... can anyone give me starting points for power and speed for black granite? Laser u said 100 power and 4.5 speed and that's not working at all. Any input would be appreciated... Thanks, Jeff.

[Bernie Fraser]

That just seems like way too much power for granite and you would blow away any detail. I can only tell you what my settings are for a Rayjet 30. Default is power 30 and speed of 50. I have even reduced the power down to 20 and got good results. Try with much lower power and much higher speed. Let us know how it goes.

[Bernie Fraser]

Jeffrey,
I will have a guess and say power 10 and a speed of 100. Only a guess and I have no idea for your machine but if you have a little piece of granite to test it out on you could try that. Disclaimer I am only on my learners for my machine and very new to lasers so my guess could be totally wrong.

[Jeffrey Dewing]

I'll keep you posted. I don't have a lot of granite to work with at the moment, so I'm trying to be careful. I'll try those settings on a small pc. and let you know what happens... Thanks.

[Jeffrey Dewing]

30 power, and 100 speed is getting me in the ball park. still not happy though...

[Bernie Fraser]

Could you post a photo of your results?, and some granite engraves better than other. The really dark fine grain is what works for me. Also you may have to adjust the brightness and contrast in your file to get a good end result. Hopefully somebody else can help who has the same model machine.

[Bill George]

Could you post a photo of your results?, and some granite engraves better than other. The really dark fine grain is what works for me. Also you may have to adjust the brightness and contrast in your file to get a good end result. Hopefully somebody else can help who has the same model machine.

The Search function here brings up such good results, you can read and learn for hours. With all the new folks with questions.... most have been asked before, try the search first.

[Ross Moshinsky]

What is the default setting in Trotec's driver? I'd start with that and tweak from there.

[Scott Shepherd]

What is the default setting in Trotec's driver? I'd start with that and tweak from there.

Unfortunately, the default is 100 power, 4.4 speed. Why? I have no idea. The factory settings are really bizarre on some things. Some have reasoning, some, I don't understand.

Jeffrey, get the machine running, and in Job Control, you can click on the setting for the black while it's running, change the value, and hit enter and it'll change the power on the fly. Send a photo over, start engraving it, change the power as it goes down until you get it where you like it, then change the material database to reflect that setting (there's also a "save" button next to the power setting that should do that for you). Should only take a couple of minutes to get it dialed in and set.

[Bert Kemp]

are you sealing the granite first with a stone sealer sorry if I missed that.

[Jeffrey Dewing]

Thanks Scott, The default setting for granite is nuts. I'm now in the ball park and can use your method to tweek my result once I get some more laser grade granite. The save button next to the power setting is news to me and will be great on many substrates if it remembers the setting when it's sent over from corel. Thanks again!

[Don Corbeil]

Thanks Scott, The default setting for granite is nuts. I'm now in the ball park and can use your method to tweek my result once I get some more laser grade granite. The save button next to the power setting is news to me and will be great on many substrates if it remembers the setting when it's sent over from corel. Thanks again!


There's also a export/import function in the material database tab, so that when you get the settings where you like them you can export them to an .xml file. I back mine up once in awhile in case of a crash or loss of settings.

Scott (Steve), I didn't know there was an 'on the fly' power adjustment option. That's a great thing to know. Another reason I really like trotec job control... gotta love it.

edit: steve

[Bill George]

http://www.sawmillcreek.org/showthread.php?171122-Tips-for-Lasering-Granite-tiles-with-Photos

[Jeffrey Dewing]

No, I'm engraving on a finished, or polished surface. I don't think there is anything on it, but It's been polished to a mirror finish.

[Andrey Anfimov]

Please, look at http://www.sawmillcreek.org/showthread.php?99125-How-to-find-correct-power&highlight=power

You can find correct power of laser for any material fast and easy.

[Jeffrey Dewing]

305094Came out fare I think....

[Jeffrey Dewing]

305155305156 Not bad...

[Jeffrey Dewing]

30523930P. 100S. on my 80watt Trotec

[Jeff Belany]

Are you going to add some white pait to these? Really makes them much better IMHO.

As far as changing speed/power on the fly -- the Epilog will kind of do this, not exactly on the fly. Send a job with power high (or speed of you want to check that), start the job and let in burn an inch or so. Then hit stop, then you can change the power by 10 or so and run another inch. Keep doing this and you get a real good idea how things sre going to look. Save these test pieces for future reference.

Jeff in northern Wisconsin