Problem on 0402 package

They say "the pads are too much large" and a lot of components are lost

Can it be compared to Cream area, like Cream "hole" not same as pad size.

In DRC | Masks | Cream, my Cream settings are 0mil, ie not extra area for

cream

Maybe could be check with gerber viewer or reading gerber files.

Also 0402 can come from different libraries, like rcl, and other libraries.

Is the problem on all 0402 or only some kind of them (resitors only)

If problem is too less solderpaste on board, maybe the boardhouse has

ordered too thin a pastemask for production.

Just my thoughts...

Christen

Il 02/08/2010 15.41, Christen Fihl ha scritto:

Can it be compared to Cream area, like Cream "hole" not same as pad size.

>

In DRC | Masks | Cream, my Cream settings are 0mil, ie not extra area for

cream

Maybe could be check with gerber viewer or reading gerber files.

The same applies here.

Also 0402 can come from different libraries, like rcl, and other libraries.

Is the problem on all 0402 or only some kind of them (resitors only)

For all components (resistors and capacitors).

If problem is too less solderpaste on board, maybe the boardhouse has

ordered too thin a pastemask for production.

If I'm not wrong they told me there was too much solderpaste so the

components moved from their position.

Marco

If I'm not wrong they told me there was too much solderpaste so the

components moved from their position.

What can too much paste do?

1) Spread to other pads?

2) ??

The solder should hold the components in place, if they get into contact

with each others. The surface tension will pull components into center

I have had same problem (tombstone) in my home office (50$ oven in the

garden), as some resistors only soldered on one end, leaving the other end

up in the air.

Here my solder paste might have dried out a bit before mounting components,

so they did not get into contact, or I simply did not press them firmly

enough onto the board (into the solderpaste).

PS: I have not worked with 0402, smallest are 0805, as I do my own

prototypes, and I am getting older...

I would check my pad size, and ask what size the company request. Too-much

is not that precise specification

If I'm not wrong they told me there was too much solderpaste so the

components moved from their position.

What can too much paste do?

1) Spread to other pads?

2) ??

The solder should hold the components in place, if they get into contact

with each others. The surface tension will pull components into center

I have had same problem (tombstone) in my home office (50$ oven in the

garden), as some resistors only soldered on one end, leaving the other end

up in the air.

Here my solder paste might have dried out a bit before mounting components,

so they did not get into contact, or I simply did not press them firmly

enough onto the board (into the solderpaste).

PS: I have not worked with 0402, smallest are 0805, as I do my own

prototypes, and I am getting older...

I would check my pad size, and ask what size the company request. Too-much

is not that precise specification