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Questions relating to designing PCBs
By RC
#52136
I'm just getting started with Eagle and working on my first board. If the Pads layer is on the bottom of the board, how do a create a header that is installed on the bottom of the board with solder pads on the top like SFE's breadboard supply? Thanks.
User avatar
By bigglez
#52141
Greetings Rick,
RC wrote:If the Pads layer is on the bottom of the board, how do a create a header that is installed on the bottom of the board with solder pads on the top like SFE's breadboard supply?
That's a wrong assumption, the Pads layer is independent
of any other layer. Objects (pads) on layer 17 are printed
in copper on all external layers, and with smaller diameter
on internal layers (i.e. more than two layer boards).

To learn more run the DRC (in the board editor) and select
the "Restring" tab. There is a pictorial sectional view of a
PTH (Plated Through Hole), from which you can see the
EAGLE nomenclature.

For a newbie a lot of this jargon will be as clear as mud.
Stick with it, when you have one board back from the
PCB house it will start to make sense.

Comments Welcome!
By RC
#52150
So if the top and bottom settings for Pads on the Restring tab of the DRC are the same, I'll get a solder pad on both the top and bottom of a two layer board. Is that correct? My layers setup is the default (1*16).
By lou
#52157
RC wrote:how do a create a header that is installed on the bottom of the board with solder pads on the top like SFE's breadboard supply? Thanks.
If you use the mirror tool (the icon is a rectangle with a dotted line across the middle, and it's immediately below the move tool (at least it is in version 4.15)), you can move the header from one side of the board to the other.
User avatar
By bigglez
#52158
Greetings Rick,
RC wrote:So if the top and bottom settings for Pads on the Restring tab of the DRC are the same, I'll get a solder pad on both the top and bottom of a two layer board. Is that correct?
Yes.

If you are asking about flipping a polarized component to
the "solder" side from the "component" side (in effect
making a two sided PCB with parts on both sides, you
will need to mirror the parts from the component side.
(As noted by Lou in another post).

In all PCB CAD work the final PCB is viewed from above,
and both the components and PCB core are transparent.
For example, any wording on the "solder" side will be
mirrored when viewed.

A good way to grasp these concepts is to throw a few
familiar parts on a test PCB design, and run the CAM
job to create Gerber output files.

These may be viewed independently of EAGLE using a
(freware or shareware) third party Gerber viewer. The
Gerbers are the master phototools that are printed on
to the copper at the board house. (If you print them to
paper you can make a model of your PCB before
committing to production - a useful way to catch
placement errors).

Comments Welcome!