Inconsistent Engraving on Anodised Aluminium Upgraded K40

Discuss laser machine here freely.

Moderator: baker

Post Reply
Adolphei
Posts: 11
Joined: Sun Aug 09, 2015 1:06 pm

Inconsistent Engraving on Anodised Aluminium Upgraded K40

Post by Adolphei »

I recently managed to convert the K40 to the lightobject DSP and running with Lasercad. I'm happy with the machine overall, given its price. It cuts and engraves wood and acrylic well.

I have a frustrating problem engraving white on anodised aluminium though.

The example I have attached used X Swing with speed 20 and power 14 and PPI 1200. I've tried many other settings, but the results are mixed. Either the engraving doesn't turn out bright white, or the engraving comes out bight white but with the burnt section where the laser starts the job. I have tried making sure that the work table is level, that the laser is aligned properly, and that nothing is loose. It doesn't solve the problem. I am using a good quality 38mm lens bought separately from lightobject.

In the image you can see that the top of the text appears darker than the rest, while the remaining text comes out perfectly fine. The top part looks like it has been burnt to the metal almost, as though the machine has applied too much power.

The real size of the engraving is about 7mm across so the image has been enlarged quite a bit.
Stanleydaph
Posts: 5
Joined: Thu Aug 06, 2015 10:09 am

Re: Inconsistent Engraving on Anodised Aluminium Upgraded K40

Post by Stanleydaph »

I think you are using too much power. I have had some problems before. I think the type and thickness of anodizing makes a big difference too. Sometimes it is really easy to get a nice white mark, other times it will remove the entire oxide layer and the bare aluminum shows through. Just reduce the power enough to prevent the burn through while still having a nice mark.
Post Reply