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Questions relating to designing PCBs
By slide
#30528
I've been using Ealge for a little while now, but there are some things that I do (people have told me to do specifically) and I don't know why.

What is 'isolate' for?
Some footprints I have, when I smash them, and delete both labels, they always come back and I don't want them!
I have a gnd poly on the top layer and for any circular through hole connection it always just uses a couple straight lines, why doesn't it just surround the entire pad?
How can I get the gnd poly TO surround the entire pad so its not just the crosshair thing?
User avatar
By bigglez
#30532
slide wrote: I've been using Ealge for a little while now, but there are some things that I do (people have told me to do specifically) and I don't know why.
Greetings slide,

EAGLE is a very powerful tool. I had done CAD (and manual layouts) before using it, but I found the learning curve to be quite steep.

slide wrote:What is 'isolate' for?
Isolate: Distance between polygon areas and other signals or objects in the Dimension layer (default: 0).

In other words, if you flood a layer to make a ground (or power) plane, this is the distance from the edge to other features (vias or pads, the board outlien, for example).
slide wrote:Some footprints I have, when I smash them, and delete both labels, they always come back and I don't want them!
Hmm. Not sure what you mean or intend. I also find the SMASH command confusing. Are you SMASHing existing parts or ones that you created (in the library editor)? Use SMASH to isolate the >NAME >VALUE text (so that you may move or delete then).
slide wrote:I have a gnd poly on the top layer and for any circular through hole connection it always just uses a couple straight lines, why doesn't it just surround the entire pad?
That is called a thermal. It is a break to stop the large plane form robbing heat from the via or pad when it is soldered. You can turn it off (Change -> Thermal -> On|Off). A board with planes and no thermals may be hard to solder.
slide wrote:How can I get the gnd poly TO surround the entire pad so its not just the crosshair thing?
Change -> Thermal -> Off

Comments Welcome!
By Philba
#30534
the deleting labels thing is a feature, not a bug. Not that I agree with the feature, though. You could just turn off the layers.

Smash is a very misnamed feature though I've often thought that there is no really good name for it. It seems to me that all lib devices should come pre-smashed,

I would not turn off thermals. they exist to make it easy to solder the pad. what happens if you don't have them is the surrounding copper sucks up a lot of heat and it takes a long time to raise the copper temperature to the point where the solder will flow.
By NleahciM
#30635
Philba wrote:the deleting labels thing is a feature, not a bug. Not that I agree with the feature, though. You could just turn off the layers.
It's always annoyed the heck out of me. I typically just delete one of the labels and drag the other off the PCB.