Single-layer Aluminium PCB Solder Mask

[dave_kelman]

Hi,

I have completed the layout for the singe-layer Aluminium PCB I want but the preview for this is showing the small copper dots I have used to help part orientation without solder mask covering, how can I have these covered by the mask?

I created the copper dots as a device without any connections, is there a better way?

NB because the design will be clean white other than the led's and connection points, silk-screen isn't an option

Thanks,

David

[jorge_garcia]

Hi @dave_kelman ,

I hoe you're doing well. If you cover those dots with solder mask, won't that create problems for the pick and place machine? Those dots are called fiducials and the machine needs to be able to see the copper to locate parts. Sometimes they can be covered but I would recommend talking to your board house and see if their manufacturing process can cope with the fiducials being covered.

Let me know if there's anything else I can do for you.

Best Regards,

[dave_kelman]

Hi Jorge,

Thanks for your reply.

In this instance, the copper dots were positioned by me as a help for my manual component placement but it's good to know about fiducials for the future.  

The original board I'm using for guidance has small copper + markings under the solder-mask but I couldn't find a way in Fusion to place these in copper so I went with dots derived from pads but I'm guessing this is why the solder-mask isn't covering them?  

It would be great if you could suggest another method in Fusion I could use to be able to mark a single-layer board with copper symbols that would be covered by the solder-mask.

Best regards,

David

[jorge_garcia]

Hi @dave_kelman ,

I hope you're doing well. Thanks for the explanation. If you want to have the fiducials covered with Stopmask then you can edit the fiducial in the library and remove the stopmask there. Stop mask is a property of the SMD pad so in the library click on the pad and then uncheck the Stop check box in the inspector.

Let me know if there's anything else I can do for you.

Best Regards, 

[dave_kelman · Accepted solution]

Works just as I wanted, thanks Jorge

Best regards,

David