kicad-developers team mailing list archive

[Rok Markovic <rok@...>]

Hi

There are still some problems with thermals. One, that I encounter in my
boards is when in close pitch components (VQFP, ... ) two neighbouring
pads are on zone. When drawing thermal holes in such a situation, each
neighbouring pad draws around itself a hole. This hole cuts the thermal
connection to other pad. Please see atached pictures, I understand if my
explanation is unclear.

The only option I see is to add thermal connections after removing all
pads from zones. I understand that this concept has problems (DRC), but
I would like to ask if it CAN be done.

Rok


jean-pierre charras - INPG pravi:
> Vesa Solonen a écrit :
>> Polygon edge tracer has a following bug. It doesn't take care about
>> tracer line width on inside edges like miters on oval thermals. Miter
>> size changes while changing minimum width parameter. Would you look at
>> it Jean-Pierre?
>>
> Is really a bug ? just needs refinements.
> The main goal of this miter is to avoid (or reduce) problems with kbool.
> 
> So i am not sure the current code must be changed.
> In fact a full optimization is better:
> 
> Now we have a good idea about what thermal shapes calculations must be 
> done (including unused stubs removal)
> 
> A full optimization could be:
> a -calculate filled areas including pads (as now)
> b- test for unused stub (currently done after creating thermal shapes) 
> ising the current code.
> c - creating thermal shapes using a more refined shape calculations 
> taking in account the fact some stubs must be created, and others not.
> and remove shapes (that do not have any unused stub) from filled areas 
> (now thermal shapes are removed, and after unused stubs are removed)
> So because unused stubs are not created one can expect also better 
> thermal shapes
> 
> Calculation time will be shorter, because polygon calculations are made 
> 3 time (create filled areas, remove thermals, remove stubs),
> and could be made only twice, with better thermal shapes (including 
> miter enhancements, 24 or more segments per 360 deg arc approx ... ).
> 
> I believe you are volunteer to refine thermal shape calculation. Am i 
> wrong ?

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