better mouse bites

[John Larkin]

I'm using mouse bites to mount one PC board on another PC board.

https://www.youtube.com/watch?v=LFrdqQZ8FFc

First pass on this little board, I centered the contact pads on the
board edge and routed them in half.

https://www.dropbox.com/s/7bsc43mtvkvyiyn/T577A_Mice.jpg?raw=1


I found those to be a bit hard to solder and desolder. So on rev B, I
moved the pad centers off the board by 10 mils. That's quite a bit
better.

https://www.dropbox.com/s/2ybu9qrd5304xr3/T577B_Panel_Back.JPG?raw=1

https://www.dropbox.com/s/e7yzccyoie2ob2s/T577B_Mice.jpg?raw=1

I might try another 10 mils next time, and maybe make the drill
(currently 60 mils) a little bigger, to get a shallower bite.

I've seen boards with basically just a stripe of copper on the edge.

 

[John Robertson]

On 2019/09/30 3:14 p.m., John Larkin wrote:

I'm using mouse bites to mount one PC board on another PC board.

https://www.youtube.com/watch?v=LFrdqQZ8FFc

First pass on this little board, I centered the contact pads on the
board edge and routed them in half.

https://www.dropbox.com/s/7bsc43mtvkvyiyn/T577A_Mice.jpg?raw=1


I found those to be a bit hard to solder and desolder. So on rev B, I
moved the pad centers off the board by 10 mils. That's quite a bit
better.

https://www.dropbox.com/s/2ybu9qrd5304xr3/T577B_Panel_Back.JPG?raw=1

https://www.dropbox.com/s/e7yzccyoie2ob2s/T577B_Mice.jpg?raw=1

I might try another 10 mils next time, and maybe make the drill
(currently 60 mils) a little bigger, to get a shallower bite.

I've seen boards with basically just a stripe of copper on the edge.

Watch out for Lyme disease - so be sure to disinfect the mouse bits
prior to use...

John ;-#)#

 

[John Larkin]

On Mon, 30 Sep 2019 16:38:11 -0700, John Robertson <spam@flippers.com>
wrote:

On 2019/09/30 3:14 p.m., John Larkin wrote:

I'm using mouse bites to mount one PC board on another PC board.

https://www.youtube.com/watch?v=LFrdqQZ8FFc

First pass on this little board, I centered the contact pads on the
board edge and routed them in half.

https://www.dropbox.com/s/7bsc43mtvkvyiyn/T577A_Mice.jpg?raw=1


I found those to be a bit hard to solder and desolder. So on rev B, I
moved the pad centers off the board by 10 mils. That's quite a bit
better.

https://www.dropbox.com/s/2ybu9qrd5304xr3/T577B_Panel_Back.JPG?raw=1

https://www.dropbox.com/s/e7yzccyoie2ob2s/T577B_Mice.jpg?raw=1

I might try another 10 mils next time, and maybe make the drill
(currently 60 mils) a little bigger, to get a shallower bite.

I've seen boards with basically just a stripe of copper on the edge.


Watch out for Lyme disease - so be sure to disinfect the mouse bits
prior to use...

John ;-#)#

All our mice go through a solvent wash.

 

[John Robertson]

On 2019/09/30 5:09 p.m., John Larkin wrote:

On Mon, 30 Sep 2019 16:38:11 -0700, John Robertson <spam@flippers.com
wrote:

On 2019/09/30 3:14 p.m., John Larkin wrote:

I'm using mouse bites to mount one PC board on another PC board.

https://www.youtube.com/watch?v=LFrdqQZ8FFc

First pass on this little board, I centered the contact pads on the
board edge and routed them in half.

https://www.dropbox.com/s/7bsc43mtvkvyiyn/T577A_Mice.jpg?raw=1


I found those to be a bit hard to solder and desolder. So on rev B, I
moved the pad centers off the board by 10 mils. That's quite a bit
better.

https://www.dropbox.com/s/2ybu9qrd5304xr3/T577B_Panel_Back.JPG?raw=1

https://www.dropbox.com/s/e7yzccyoie2ob2s/T577B_Mice.jpg?raw=1

I might try another 10 mils next time, and maybe make the drill
(currently 60 mils) a little bigger, to get a shallower bite.

I've seen boards with basically just a stripe of copper on the edge.


Watch out for Lyme disease - so be sure to disinfect the mouse bits
prior to use...

John ;-#)#

All our mice go through a solvent wash.

That does indeed solve the problem...

John ;-#)

 

[Robert Baer]

John Larkin wrote:

I'm using mouse bites to mount one PC board on another PC board.

https://www.youtube.com/watch?v=LFrdqQZ8FFc

First pass on this little board, I centered the contact pads on the
board edge and routed them in half.

https://www.dropbox.com/s/7bsc43mtvkvyiyn/T577A_Mice.jpg?raw=1


I found those to be a bit hard to solder and desolder. So on rev B, I
moved the pad centers off the board by 10 mils. That's quite a bit
better.

https://www.dropbox.com/s/2ybu9qrd5304xr3/T577B_Panel_Back.JPG?raw=1

https://www.dropbox.com/s/e7yzccyoie2ob2s/T577B_Mice.jpg?raw=1

* First impression is the PCB material is crappy: i have never seen
laminations like that before, and so many...

I might try another 10 mils next time, and maybe make the drill
(currently 60 mils) a little bigger, to get a shallower bite.

I've seen boards with basically just a stripe of copper on the edge.

 

[TTman]

On 30/09/2019 23:14, John Larkin wrote:

I'm using mouse bites to mount one PC board on another PC board.

https://www.youtube.com/watch?v=LFrdqQZ8FFc

First pass on this little board, I centered the contact pads on the
board edge and routed them in half.

https://www.dropbox.com/s/7bsc43mtvkvyiyn/T577A_Mice.jpg?raw=1


I found those to be a bit hard to solder and desolder. So on rev B, I
moved the pad centers off the board by 10 mils. That's quite a bit
better.

https://www.dropbox.com/s/2ybu9qrd5304xr3/T577B_Panel_Back.JPG?raw=1

https://www.dropbox.com/s/e7yzccyoie2ob2s/T577B_Mice.jpg?raw=1

I might try another 10 mils next time, and maybe make the drill
(currently 60 mils) a little bigger, to get a shallower bite.

I've seen boards with basically just a stripe of copper on the edge.

We did something similar when a memory chip went obsolete... trouble was
that after reflow soldering, there were 'dry joints' on some of the
'pads' to the main pcb. Hand soldering was not an option as we had to do
thousands... In the end, bad joints had to be touched up. Could be we
missed some and they would have ended up as early field failures......

--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

 

On Tue, 1 Oct 2019 11:55:47 +0100, TTman <kraken.sankey@gmail.com>
wrote:

On 30/09/2019 23:14, John Larkin wrote:

I'm using mouse bites to mount one PC board on another PC board.

https://www.youtube.com/watch?v=LFrdqQZ8FFc

First pass on this little board, I centered the contact pads on the
board edge and routed them in half.

https://www.dropbox.com/s/7bsc43mtvkvyiyn/T577A_Mice.jpg?raw=1


I found those to be a bit hard to solder and desolder. So on rev B, I
moved the pad centers off the board by 10 mils. That's quite a bit
better.

https://www.dropbox.com/s/2ybu9qrd5304xr3/T577B_Panel_Back.JPG?raw=1

https://www.dropbox.com/s/e7yzccyoie2ob2s/T577B_Mice.jpg?raw=1

I might try another 10 mils next time, and maybe make the drill
(currently 60 mils) a little bigger, to get a shallower bite.

I've seen boards with basically just a stripe of copper on the edge.

We did something similar when a memory chip went obsolete... trouble was
that after reflow soldering, there were 'dry joints' on some of the
'pads' to the main pcb. Hand soldering was not an option as we had to do
thousands... In the end, bad joints had to be touched up. Could be we
missed some and they would have ended up as early field failures......

We'll hand solder these baby boards to the main boards. I don't want
to re-reflow them. This is high price stuff, and there are only 10
connections, so it's no big deal.

The real motivation here is to not have to rework a blown GaN fet;
just replace the baby board. The BGA fets are fragile, so need to be
glob-topped, so are impossible to rework.






--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

On Mon, 30 Sep 2019 21:59:28 -0800, Robert Baer
<robertbaer@localnet.com> wrote:

John Larkin wrote:

I'm using mouse bites to mount one PC board on another PC board.

https://www.youtube.com/watch?v=LFrdqQZ8FFc

First pass on this little board, I centered the contact pads on the
board edge and routed them in half.

https://www.dropbox.com/s/7bsc43mtvkvyiyn/T577A_Mice.jpg?raw=1


I found those to be a bit hard to solder and desolder. So on rev B, I
moved the pad centers off the board by 10 mils. That's quite a bit
better.

https://www.dropbox.com/s/2ybu9qrd5304xr3/T577B_Panel_Back.JPG?raw=1

https://www.dropbox.com/s/e7yzccyoie2ob2s/T577B_Mice.jpg?raw=1
* First impression is the PCB material is crappy: i have never seen
laminations like that before, and so many...

It's a perfectly fine 4-layer board from Cirexx. It's fabbed as a
panel array, and we break apart the little tiles after assembly. I
think we'll arrange to test and glob-top them before break-apart too.

Gotta make a test fixture with pogos.



--

John Larkin Highland Technology, Inc

lunatic fringe electronics