We often encounter special process problems during the PCB production process.

We often encounter special process problems during the PCB production process.

1. Thickness
1) The copper thickness of the wall of the plated-through holes is specified as 0.001". It's too tight for our production. We suggest as per IPC class 2. that's to say, It's 0.0008".
2) The plating thickness of Au in edge contact is specified as 1.2-1.5um, it is too tough for us, we suggest following our normal standard, that is to say, 0.45um instead.
3) The copper thickness is specified as 2OZ. We suggest a finished copper thickness 2OZ. And we will use the base material with 1.5OZ copper thickness and plate to 2OZ for our production.
4) The solder thickness is required to be plated 0.0005-0.003", We can not reach the requirement. We suggest following IPC class 2 for the solder thickness and we will assure the solderability.
2. Tolerance
1) The tolerance of dimension is specified as XXX.+/-0.005" .It is tight for our production . We suggest +/-0.008" instead。
2) The profile tolerance is specified as +/-0.005" in *.pdf file. We suggest as per IPC class 2, that is to say, it is +/-0.01".
3) The tolerance of the board thickness is specified +/-0.007" in layup detail which is different from NOTES 1 +/-0.005".We suggest 0.062"+/-0.007" is acceptable for +/-0.005" is very tough for us to control.
4) The tolerance of the outline is specified at +/-0.1mm. It's above us. We suggest +/-0.2mm instead.
5) The remaining tolerance of v-cut is specified as +/-0.06mm and the offset tolerance is +/-0.05mm. they are too tight for us, we suggest both tolerances are +/-0.1mm instead.
6) The tolerance of the hole position is specified as 0.05mm. It's too tight for us, We suggest +/-0.076mm instead.
7) The tolerance of the angle is +/-0.5 degrees, it is tight for us, and we would like to control the angle of the v-cut within 30+/-5 degrees.
8) It is special that the tolerance of the hole to the board center is +/-0.05mm in the 1MB5476-01.pdf file, it is too tight for us, we suggest as per IPC class 2.
9) It stated that conductor width and spacing shall be within +/-0.03(0.001) of Gerber data, it is tight for us, and we would like to relax to +/-20%. Please confirm.
10) The tolerance of the holes with a diameter of 3.0mm is required to control within +0.05mm, it is tight for us, and we would like to relax to +0.1/-0mm. Please confirm.

3. Pattern Layer
3. Pattern Layer
1) Two holes are near the outline, which will cause copper exposed and the hole to break, we suggest copper exposed and hole damaged is permitable.
2) Some pads are close to the outline. We suggest shaving the pads about 0.4mm avoid to the copper exposure.
3) The copper pad extends to the board outline, it will lead to copper exposure if we follow Gerber to do, We suggest copper exposure is acceptable.
4) The three pads are so close to the v-cut that they will cause copper exposure. We suggest shaving the pads 0.4mm to avoid copper exposure.
5) The copper grids on the bottom side are only 0.178mm in some places, we can not do it per this gap, so we suggest decreasing the trace width to make copper grids to 0.2mm.
6) We suggest putting some extra copper on the waste tab in all layers to improve plating quality since this is no functional effect.
7) We suggest putting some copper in a blank area on the top side to improve plated quality.
8) We have found that the gap between two blocks of copper is only 0.013mm on the bottom side, we suggest they are connected.
9) The two fiducial marks are over the v-groove line. They will be cut. We suggest moving them 1.0mm toward the left.

4. Profile Layer
1) The unit outline can’t match the panel profile. We suggest following the unit outline to modify.
2) The actual Gerber dimension is different from the description in the drill chart. we suggest per actual Gerber.
3) We suggest the remaining v-cut line as per the old version. (0.3+/-0.1mm).
4) The angle of V-CUT is specified as 30-45 degrees. But our normal reamer of V-CUT is only 30,45,60 degrees. Their tolerance is +/-5 degrees. So we have to suggest the angle of V-CUT 30+/-5 degree is permitted.
5) We suggest waste tabs connected around the panel to have it more robust.
6) We did not find the outline of the board in the Gerber file, please send the outline Gerber file to us, otherwise we can not manufacture this board.
7) The slots are only 1.0mm in the original Gerber, can we expand them to 2.0mm to improve our production efficiency?
8) The gap between snap-off holes is only 0.15mm, and the size of the board is large. We suggest decreasing the snap-off holes (dia.0.599mm) to 0.45mm to get the web stronger.