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Dave Johnson29
11-03-2008, 10:16 AM
Hi,

I am not sure if it makes any difference but the Y carriage is much lighter than the X so do you force the rastering on the X-axis by rotating text to vertical, or does it not really matter enough?

I would assume the Y would be faster and more accurate as acel/decel times could be faster.

Stephen Beckham
11-03-2008, 12:11 PM
Dave,

I'm not sure what you are reffering to as 'lighter' between X and Y.

My focus is on laser time. A single text line say 24 font put in horizontally may run 10-15 seconds of laser time.

The same line rotated (Plaque and all) will cause about a 3 to 4 minute burn do go down the Y axis. Your call, but I always rotate my plaque and all to try and keep my text horizonally to preserve burn time.

I worry about dark or lightness of the character related to DPI, speed and power.

Steve

Joe Pelonio
11-03-2008, 12:21 PM
I have seen that problem, like when engraving a grid, the vertical lines are much lighter/thinner than the horizontal. The solution is in creating the artwork, try making the vertical lines 1/2 point thicker than the horizontal,
that works on mine.

Rotating the work only helps when you have all vertical lines, and you are not using a material with a brushed surface where there's a correct direction.

Dave Johnson29
11-03-2008, 12:45 PM
I'm not sure what you are referring to as 'lighter' between X and Y.


Hi Stephen,

Sorry, I was talking in the mechanical sense. The X-carriage has the beam and wheel sets on both ends plus the Y-carriage, whereas the Y only has the mirror and focus lens to move. The Y-carriage probably weighs a 1/8th of the X.

I was wondering if it makes sense to rotate images and use the Y for the rastering as being lighter it should be able to travel faster.

Stephen Beckham
11-03-2008, 1:38 PM
:eek: oops....

Well, I'm not sure the difference between your ULS and my Epilog, if I were you, I'd just run some sample burns... When I'm doing narrow items just down the left side of the deck, it does seem to finish faster.

And when I'm doing three plaques side by side, I force the machine to finish one at a time then move over. Covering the whole x axis for three plaques at a time versus doing 1/3 of the axis times 3 seems to take longer.

Sorry I couldn't help more...

Steve

Richard Rumancik
11-04-2008, 11:13 AM
I am not sure if it makes any difference but the Y carriage is much lighter than the X so do you force the rastering on the X-axis by rotating text to vertical, or does it not really matter enough?

Dave, I don't quite understand what you are saying here. Firstly, most of the laser engraver manufacturers refer to the x-axis as going left to right, y axis back to front, with the origin (0,0) in the top left corner. Positive x direction to the right and positive y toward the operator. This may not be a "normal" axis convention in the CNC world, but laser engravers don't follow CNC machine conventions. I don't know how your particular machine is referenced.

Using this coordinate system, it is the x-carriage that is lighter. To raster, the x-carriage moves left and right, while the x-rail/carriage assembly advances a line at a time in the y direction. The y axis is carrying the heavy load as it moves the whole lens carriage and x-rail.

It may be possible to raster along the y axis but it would be very slow, as you would not achieve your specified laser raster speed when attempting to move the entire x-rail and carriage. I don't know of any case that would require this.

I am not even sure if my laser driver would permit it (I don't know how to "force" it as you say.) The default is to raster left to right along the x axis. It makes no difference if the text (or graphic) is aligned with this axis, rotated, mirrored, positioned at an arbitrary angle, etc. The laser will normally raster left-right regardless.

Here's a sketch from a ULS manual. I think it is typical nomenclature.

Mike Mackenzie
11-04-2008, 12:55 PM
Richard,

Not on his system the 1720 systems were orientated opposite with the X and Y directions. These systems used a Roland plotter motion system.

Dave you could probably save some time by rotating the graphic although those systems did not move very quickly to begin with so you probably won't see much difference.

Also there is a portrait / Landscape switch in the driver

Dave Johnson29
11-04-2008, 1:02 PM
Dave you could probably save some time by rotating the graphic although those systems did not move very quickly to begin with.


Hi Mike,

Thanks for that. The thing moves fast enough, I am just a speed-optimizing junkie. <g>

I posted the manual back on Monday. Thank you very much it was a great help.

Mike Mackenzie
11-04-2008, 1:07 PM
Dave,

I did get it back thank you, I am now searching for page 16 I am not sure why it is missing or if I ever had it. I have a couple of other boxes of the old stuff maybe it is in there. If I find it I will scan an e-mail it to you.

Richard Rumancik
11-05-2008, 11:38 AM
Richard . . . the 1720 systems were orientated opposite with the X and Y directions. These systems used a Roland plotter motion system.
. . . those systems did not move very quickly to begin with so you probably won't see much difference. Also there is a portrait / Landscape switch in the driver

Thanks for the info Mike . . . that explains why his post was a bit confusing . . . and since you noted that that system was quite slow, it also explains why you could actually raster in both axes. If you are moving at 5 or 10 ips maybe the penalty of moving the heavier mass when rastering was not such a big issue - but with newer machines it would take many times longer to raster parallel to what we now call the y axis so is not really practicable.