Thermal spoke orientation

[eeintech]

Hello there,

I was curious to know how is the thermal spoke orientation determined for the zone connect and if there is a setting at the pad level (or elsewhere) to select between 45-degree angle and straight spokes.

In my design I found that there is both orientation for the same zone for 2 different connectors/pads:

45 degree angle spokes

Straight spokes

I came curious as I want to control the orientation for a specific connector (from 45-degree to straight) but haven’t been in luck to find out how.

Thanks!

[Rene_Poschl]

One pad is oval one is circular. 45 degree on the oval one would not really work.

[jos]

It still would be useful being able to define direction in regular round/square pads.

[paulvdh]

If this settings only influences a few of the pads, then you can also set those pads to “no connection” and then draw a few tracks by hand for those pads.

[Frederik]

Why do you bother about the orientation? Risk of starving the thermal maybe?

[Rene_Poschl]

I consider rotation selection for thermal spokes a valid request as it can easily improve connectivityand therefore EMC behaviour.

[Frederik]

I do not criticize the request. I just asked why.

[der.ule]

Apparently you can rotate the pad to control where the thermal spokes are placed, from an old thread:

Number of spokes in thermal relief

I tried rotating pads by 45°, the thermal relief change to cross like. I can’t understand why I should get two spokes increasing the clearance? With small value I got 4 spokes connected to the plane, increasing the clearance over 0.4 mm I got plane disappear and remain only the 4 spokes[image]

[John_Pateman]

You can edit pads on an individual basis and rotate them by 45º. Obviously not so useful for square pads.

[eeintech]

Thanks @John_Pateman and @der.ule, your little trick works great!

@Frederik I was hidding the real reason why
I have this connector with 3 ground pads (check out the right-hand side pad):

It does not carry much current (it’s a debug connector) so I wanted thin spokes to be able to install it without too much heat dissipation from the ground plane. Unfortunately, 45-degree angle thin spokes (< 0.3mm) wouldn’t pour over the pad, changing the zone settings would result in uneven copper shape (again, see right pad):

Rotating the pad 45-degree worked like a charm!
I get only one spoke and much more relaxed clearance settings

I’m not religious but this is a really sweet Christian cross

Thanks again all!

[Frederik]

Thanks for the explanation. It is clear now.

[paulvdh]

Found this post after searching for an explanation for spoke orientation in:

I do not agree with Rene’s remark of:

@Rene_Poschl

45 degree on the oval one would not really work.

For “oval” pads the thermal spokes could easily origin from the centers of the arcs instead of from the center of the pin.
But overall it’s not very important for me. When Zone connection may become a problem It’s usually for a small number of pads and those can be easily handled by using not thermal spokes at all and drawing a few track segments that fit that particular situation.