kicad-developers team mailing list archive
Mailing list archive
Re: 3d-viewer: via diameter calculation off?
Our usage of “drill” in the terminology is pretty misleading. As far as I’m aware the vast majority of board houses treat it as “finish hole” diameter.
> On 8 Jul 2020, at 23:00, Seth Hillbrand <seth@xxxxxxxxxxxxx> wrote:
> That really depends on the manufacturer. Many manufacturers will overdrill and expand the size of their bits to account for the plating. If you are thinking of making a change like this, it would need to be an optional preference.
> Seth Hillbrand
> Lead Developer
> +1-530-302-5483 <tel:+12126039372>
> Davis, CA
> www.kipro-pcb.com <https://www.kipro-pcb.com/> info@xxxxxxxxxxxxx <mailto:info@xxxxxxxxxxxxx>
> <https://twitter.com/KiProEDA> <https://www.linkedin.com/company/kicad>
> On 2020-07-08 14:47, Joshua Redstone wrote:
>> I'm a bit new to pcbs and Kicad, but I thought that the effective diameter of a through-hole is the drill diameter minus copper plating thickness (since plating is done after drilling).
>> In the 3d-viewer code, it looks like it's increasing the drill diameter to account for the plating so the plated hole is the drill diameter rather than the unplated hole, which seems odd.
>> I was thinking of doing a diff to fix that, but wanted to check if I'm reading the code correctly.
>> Specifically, in 3d-viewer/3d_canvas/create_layer_items.cpp
>> the calculation of a hole's inner diameter is (hole_inner_radius) rather than (hole_inner_radius - [plating_]thickness). And there's a corresponding offset in the calc of the outer diameter.
>> An example: https://gitlab.com/kicad/code/kicad/-/blob/master/3d-viewer/3d_canvas/create_layer_items.cpp#L306 <https://gitlab.com/kicad/code/kicad/-/blob/master/3d-viewer/3d_canvas/create_layer_items.cpp#L306>
>> I played around with rendering some test circuits and confirmed that the rendering seems to be producing holes that are too big.
>> Am I reading this right?
>> Mailing list: https://launchpad.net/~kicad-developers <https://launchpad.net/~kicad-developers>
>> Post to : kicad-developers@xxxxxxxxxxxxxxxxxxx <mailto:kicad-developers@xxxxxxxxxxxxxxxxxxx>
>> Unsubscribe : https://launchpad.net/~kicad-developers <https://launchpad.net/~kicad-developers>
>> More help : https://help.launchpad.net/ListHelp <https://help.launchpad.net/ListHelp>_______________________________________________
> Mailing list: https://launchpad.net/~kicad-developers
> Post to : kicad-developers@xxxxxxxxxxxxxxxxxxx
> Unsubscribe : https://launchpad.net/~kicad-developers
> More help : https://help.launchpad.net/ListHelp