help to speed up a job

[Emma austin]

Hi there. Have a job engraving some clay bricks. I have done tests etc and think I have got it looking how I want, but have had huge variances in speed of job. when I look at the three I have done (admittedly different types of writing and one image), I have different settings for each and don;t have a good enough understanding of what they are.
So what are the things that affect RASTER speed?
At the moment am using 100% power and between 3-4% speed.
PPI around 400. Is this suitable? What does the setting for Z axis mean? For one it was 0, the other it was 10.0mm . Also what about Definition? does the higher number mean slower time?
What are the things that would be influencing a slow speed the most?
Also if you imagine a brick placed horizontally, with writing across the long part in a line or two, is it quicker to have it laid that way in the laser, or laid upright and vertical?

I am going to try and figure this on my own, but hoping some friendly people can save me about 20 test attempts.

Many thanks

[Rodne Gold]

2 things will influence speed the most
1) the speed setting
2) the DPI (maybe its called definition or resolution on your laser) setting (PPI normally is how many pulses the laser fires in one inch of X travel, not normally the same as DPI, but i dont know your machine)
If you set DPIi to 600 , the laser will go backward and forward 600 times in one inch of Y travel
If you set it at 150 , it will do it 150 x times and be 4x as fast
Try a lower resolution.
There are more factors involved , lower resolution might not give you enough heat in the product to make the mark , so you will have to experiment.
Im sure it will be better to engrave it like this
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than like this
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The Z axis setting is just focussing , the one brick might be thicker than another so requires a differnt Z axis setting (the Z axis is for the engraving table)

[Mike Null]

From another thread I recall that you are trying to vitrify bricks. Achieving a very high temperature is essential and may require using 1000 dpi and even breaking up the job into two or more parts. It will be difficult to increase your speed in this instance and still maintain your quality.

That said, Rodney's explanation is one with which I'd concur.

[Emma austin]

Thanks Rodney. I will have to check the manual to see which is which. Ppi is a main selection after power and speed and is in numbers like 400,500 etc. Definition is a slide along bar thing and measured from 0-100%.
So when you say resolution, are you meaning the ddi or somethin separate?
So the resolution will effect how deep the engraving would go on the bricks?
Thanks for your help :)

[Emma austin]

From another thread I recall that you are trying to vitrify bricks. Achieving a very high temperature is essential and may require using 1000 dpi and even breaking up the job into two or more parts. It will be difficult to increase your speed in this instance and still maintain your quality.

That said, Rodney's explanation is one with which I'd concur.

Thanks mike. Yes the verifying was more for interest sake. This job wants me to enrage and then colourfil ( am just spraying paint on through the mask.)
But I am still interested in trying to get the black glass look. So the higher the ddi, the deeper/more engrained the mark? Does it mean the same both vector and rastering?

[Mike Null]

Emma

I don't believe you'll get a deeper mark on clay using 1000 dpi but it should produce a darker mark. An easy experiment is to try it on wood along with your other dpi settings while leaving the power and speed constant. That will show the dpi variance in short order.

On the machines I've used the dpi setting applied to raster only.

By breaking up the drawing I was referring to, for example, Emma Austin, where I might break the name into two parts and engrave each separately. This may work better on a thin metal where you're trying to use Cermark but can't get the temperature high enough. Here a high dpi and a short drawing will cause the laser to concentrate on a smaller area thus raising the residual temperature of the material (metals and glass) so that the Cermark can be applied.

In answer to one of your early questions, rastering in the x axis is much faster than rastering in the y axis using your example.

[Emma austin]

Thanks mike. Haha just noticed the typo in my post, I meant engrave not enrage!
Will have a good play tomorrow and run tests. Seems like this DDI is what is PPI on my universal?
Someone else had saved a lot of my settings and they tend to always be around 500ppi. Will be interesting to see the speed difference and quality difference if I reduce that.

[Mike Null]

Emma

I think ULS uses the term density in place of dpi. Ppi is as Rodney explained.

[Pete Bejmuk]

my older ULS uses DPI…

[Martin Boekers]

If it just text, I believe someone posted a way to contour the texet into hairlines and then use vectoring the outlines.
This may be possible and may help.

Someone more familiar with the process may want to chime in.

[Dan Hintz]

Emma,

Without running with your version of the driver I can't say for certain, but at one (or more) times, the ULS drivers used DPI to control dot density in the X direction and the Density setting to control density in the Y direction (only in raster mode). I preferred the extra control, but ULS may have removed the functionality since my version of driver... others have verified this oddity, as well.

I'm not sure what setting you're talking about for the Z axis, as that should only be a height setting and have no effect on speed. Raising/lowering the Z height to purposefully place the beam out of focus is one way to get a thicker line to engrave at once (most often used with vectoring), but at the expense of higher power and/or slower speeds.

Engraving is typically faster if the majority of your blank space covers entire X-axis lines. Since the Y-axis movement is much slower than X-axis movement, skipping entire empty lines by moving the carriage down (rather than over) is always a help. Things get a little more interesting if the engraving is clustered in discrete, small areas across the work surface, in which case it comes down to a judgement call (the time simulator can help here).

[Mike Null]

Raising/lowering the Z height to purposefully place the beam out of focus is one way to get a thicker line to engrave at once (most often used with vectoring), but at the expense of higher power and/or slower speeds.

And usually at the expense of definition.