stripes in my output.

[inbrissy]

Hi guys,

I'm a total noob when it comes to my laser machine. I'm having a lot of fun tweaking everything and I think I'm on the right track as things are getting better but I thought I'd ask.

I've got a 3.5 laser module and using PicLaser lite. My settings are feed rate of 3000, resolution of 0.1524, at 255 and 0 for the power engraving at -45 degrees.
My first attempt gave me a whole lot of light stripes in my etch so I tried horizontally, which reduced the stripes quite substantial but as you can see they're still there.

I then increased my resolution slightly to 0.1651 and my speed down to 2300, which reduced the stripes but introduced some thin white lines. So I reduced the speed a little more and things started to look better still.

Am I on the right track with increasing the resolution and reducing the speed or am I missing something else important?

Appreciate your help.

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[Picengravertoo]

The Pixel Resolution sets the step over, so it's based on the laser's burn line width (focal point). At a 45D angle, the burn lines will be slightly closer together then using a H or V engraving angle. You say you have a 3.5 laser. Is it the 3.5W J-Tech?

The reason you get different results at different engraving angles is, the J-Tech single element glass lens does not focus to quite a round spot. How you resolve this is, raise the laser so it's way out of focus. The beam will be a rectangular shape. Loosen the screw in front of the heat sink and rotate the module so the long side of the beam is parallel with the 45D engraving angle. The blue rectangle represents the laser beam and the red line is the engraving angle.

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Tighten up the screw and move Z back down to a 3" distance from the face of the heat sink and your material. We use a piece of black anodized aluminum to focus on to see when it's the smallest. After you get it focused, secure the lens in place with a few dabs of hot melt glue from the lens thread to the heat sink/module. Always use this same engraving angle in PicLaser.

[inbrissy]

No its the L-Cheapo 3.5W module.

Thank you for that advice, I'll have a go at that and make sure the beam is parallel to the 45 degree angle and give it another go.

[inbrissy]

Ok so the problem is that my diode is mounted in the heat sink without a screw so I cannot rotate it. Luckily, its vertically placed. So I'm assuming my best angle will be vertically? I'll give that a go now and see if it fixes my line issues.

[Picengravertoo]

If the long side of the rectangle beam shape is parallel with the vertical angle, then that is what you need to use.

Remember if you use any Pixel Resolution other then .254mm, you will have to resize your image in the editor using the Auto option.

[inbrissy]

Yes I always use the auto option. Thanks mate! this has been very helpful..

Before at 45 degrees

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After at Vertical

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Much better I would say.. Any other tips to make it even better?

[Picengravertoo]

It looks like you have un-burnt lines between the burnt lines, so try making the Pixel Resolution smaller. The key to detailed laser engravings is to focus the laser beam down as small as possible.

[inbrissy]

This one was done at 0.1524. How much smaller do you recommend I go?

[Picengravertoo]

.127?

[inbrissy]

This is at 0.127. You think I need to go smaller still?

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