Affinity Designer - Adding "cutting guides" around a PNG

[benjig]

I have some hand-drawn illustrations from another illustrator which we used on a project not too long ago.

It's now being used as part of a 3D billboard (i.e. some areas of the billboard will be sticking out from the surface).

The printer company has asked us to add 'cutting guides' around the illustrations. I assume so they have a guide to cut around when adding these elements on top of the billboard.

I'm not sure how best to go about this. From what I understand, you can not add cutting guides around object automatically in Affinity Desinger (?_ so i'd need to essentially create a stroke around these objects.

However these are PNG files which are transparrent but are not vector/curves. So the strokes I get a really bumpy and not at all suitable for guides. The end result i'm looking for is the image with the pink outline. I did this manually using the pen tool - but as I have several of these objects to do, some very complicated, I'm hoping there's a better solution.

Any suggestions?

 

Edited October 5, 2022 by benjig
clarification

[GarryP]

25 minutes ago, benjig said:

I assume so they have a guide to cut around when adding these elements on top of the billboard.

Welcome to the forums @benjig

It’s probably best not to “assume” anything if it’s for an expensive public display.

Try and get the exact details of what they want first, then we might be able to help better.

Otherwise you’ll be getting guesses about a guess, and that may not lead to a good result.

[Palatino]

3 hours ago, MC909 said:

• Add a thick outer stroke, this will later serve as padding between the shape and the cut line

At this point I would like to suggest the Contour Tool. You have a better overview of the contour.

Konturführung.afdesign

[Palatino]

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