Thermal relief problem

[Greenalien]

Why do thermal relief details only show when a layer is selected, but disappear when no longer selected, and don’t subsequently get manufactured?

[scone]

I think you may need to provide a longer explanation (real screenshots are always preferred over photos of screen) and the actual project files in order to get a real answer. As it stands, I’m not sure I understand the issue in the two photos you’ve attached. It almost looks like you are viewing two different layers, one grey and one light purple. Possibly the zone on the grey layer has thermal relief set in zone properties, but the zone on the purple layer does not?

In answer to your manufacturing question, you can always check exactly what will be fabricated by viewing the Gerbers generated by KiCad in the built in Gerber Viewer. This is a good plan in general, just to double check all the layers you expect to be there are there and there are no extra Edge Cuts or similar where you don’t expect.

[Greenalien]

It’s the same layer (B/Cu) - the only difference is that in one case, the layer has been selected, by clicking on it. Thermal relief looks fine.
Deselect it, as it looks when you first open the file, and the layer is solid, with no thermal relief.

[aaron]

I looks you are looking at two different layers on your screen shots. I can’t see the side layer tool bar selection, but I am guessing Bu looks correct and de-selecting it switches the to view Fu (top layer) which is hiding the Bu layer thermal reliefs behind the annular rings. I can get cross-eyed looking a multi-layer boards with a lot going on sometimes, so here is what I suggest:

1. Hit ‘H’ to toggle the layer highlighting (or just only set one layer to be visible in the sidebar layer bar)
2. Walk through each layer one at a time with only that layer visible.

I always do this before sending a board to fab to make sure I didn’t miss something.

[Tojan]

It looks like you have two zones there which overlap each other, one with thermal reliefs on and one without. so obviously then the zone without thermal reliefs fills in the gaps created in the other zone. To fix this you could change the priorities of the zones so that the one with thermal reliefs is the “main” zone or you could just set the other zone to thermal reliefs as well.

[Greenalien]

Thanks for all the suggestions. This board isn’t my design, and as Tojan saw, I now realise that it had 2 GND layers on each side. Deleting the second ground layer restored the thermal relief. I guess the originator wanted to have higher current capacity.