Changing normal vias to b lind or burred vias

On 23.09.2016 01:04, Karl Lautman wrote:

I'm developing my first 4-layer board in v4.16.  My plan is to prototype it

with Osh Park before doing a pilot run with the final vendor.  For

aesthetic reasons (this is for a piece of functional sculpture), I'd like

the final version to use blind and, possibly, buried vias (so one side of

the PCB will be "unblemished"), but Osh only supports normal ones that go

all the way through.  It's not clear to me from the Eagle docs

1.  How to specify which type of via is created when routing on an internal

layer, or

 

2.  How to change a normal via to a blind or buried one later.

 

Any tips on either or both of these issues appreciated.  I'm wondering how

big a chore it's going to be to go back and change all the normal vias for

the production version.

Blind vias are vias you dont see, cause they are internal only, in your

case between layer 2 and 3. They normally need microvias between L1-2

and in your case, maybe between L3-4 too.

I'm not sure if I understand you, but if you want it to be "free of

holes", there are easier and cheaper ways than using blind vias.

1-If there is nothing on the board but hole mounted components, you can

just add two outer layers of nothing. A 6 layer board may be cheaper

than what you are trying to do. You will also get some artistic freedom

to draw art on the outer layers

2-Just fill the vias with solder.

3-Stop filled holes, make the diameter as small as possible, and

under DRC->Masks, set the "Limit" parameter larger than your via drill

parameter to make eagle remove stop mask over them. Also talk to your

manufacturer to make sure they can fill them. The end result will not be

as flat as when using 2 or blind+microvias, but sufficient to keep

dirt/humidity out.

4-Copper filled vias. You need to find a manufacturer that can do that

and actually talk to them about it. If your design has PAD's, you need

to make your own CAM file to output VIAs in a separate file, so they

don't fill your PADs too.

On 23.09.2016 01:04, Karl Lautman wrote:

I'm developing my first 4-layer board in v4.16.  My plan is to prototype it

with Osh Park before doing a pilot run with the final vendor.  For

aesthetic reasons (this is for a piece of functional sculpture), I'd like

the final version to use blind and, possibly, buried vias (so one side of

the PCB will be "unblemished"), but Osh only supports normal ones that go

all the way through.  It's not clear to me from the Eagle docs

1.  How to specify which type of via is created when routing on an internal

layer, or

 

2.  How to change a normal via to a blind or buried one later.

 

Any tips on either or both of these issues appreciated.  I'm wondering how

big a chore it's going to be to go back and change all the normal vias for

the production version.

Blind vias are vias you dont see, cause they are internal only, in your

case between layer 2 and 3. They normally need microvias between L1-2

and in your case, maybe between L3-4 too.

I'm not sure if I understand you, but if you want it to be "free of

holes", there are easier and cheaper ways than using blind vias.

1-If there is nothing on the board but hole mounted components, you can

just add two outer layers of nothing. A 6 layer board may be cheaper

than what you are trying to do. You will also get some artistic freedom

to draw art on the outer layers

2-Just fill the vias with solder.

3-Stop filled holes, make the diameter as small as possible, and

under DRC->Masks, set the "Limit" parameter larger than your via drill

parameter to make eagle remove stop mask over them. Also talk to your

manufacturer to make sure they can fill them. The end result will not be

as flat as when using 2 or blind+microvias, but sufficient to keep

dirt/humidity out.

4-Copper filled vias. You need to find a manufacturer that can do that

and actually talk to them about it. If your design has PAD's, you need

to make your own CAM file to output VIAs in a separate file, so they

don't fill your PADs too.