Richard Boyle

Richard Boyle has submitted responses to the following questions.

How To Remove Oxidation On SMT Components
It is always difficult to remove oxidation once formed and is dependent on how safety critical the devices are. Ideally ...

Baking Old PCBs Prior To Reflow
You are baking the boards to ensure that there is no moisture, if they are sealed and all the moisture ...

Solder Joint Blow Holes
Potentially it could, one of the results of using a HASL finish is that the surface of pads are never ...

Contamination From Anti-static Foam
Before soaking the whole board I would look to try any cleaning solvent you try to se on a small ...

Selective Solder System Purchased At Auction
You have a few options, but first you might want to check if the machine is compatible to run lead ...

Concerns With Silver Finish Component Leads
Silver finish should not be an issue, just make sure it is not dissolved in the soldering process. ...

Extending Shelf Life for Jars of Solder Paste
Firstly ask the supplier their advice, alternatively carry out a simple solder balling test Cut 3 circles out of a ...

BGA Joint Voids - Accept or Reject?
Reject the joint, the level of voids and where they are would look to be too high, I would x-ray ...

Insufficient Barrel Fill on Through-hole Components
The answer is 'it depends.' The IPC has an inspection standard for finished assemblies and I think it is 610 ...

Conformal Coating Over Heat Sinks
It will not stop the heat sinks from working but may reduce their efficiency, but leaving them uncovered also increases ...

Black Land Edges
Thegold at the edge of pads and at through hole can be substantially thinner thanover the rest of the pad. ...

Variation in Solder Paste Thickness
Thelikely cause is that the paste is being robbed from the slightly largeraperture / pads. It may sound strange but ...

Glued SMT Components Falling Off
There are a number of reasons why components might fall off, but if this is happening after cure but not ...

Gold Plated Hole Defects
Gold is the best finish to use to stop oxidization of the boards but is not always the easiest to ...

Electroplating Over Solder Joints
I would go withpure tin as it would be the most conductive and also cut out the risk of issueswith ...

Mixing Solders
Absolutelynot, for all practical and most physical and chemical reasons, they areidentical before,during and after the soldering process so mixing ...

Stencil Design Guidelines
It is definitely a very good place to start, you may find that for your particular process a modification from ...

Wave Solder Pot Contaminated with Lead
If you add fresh Pb free alloy of the correct amount to reduce the % of Pb to below the ...

Re-qualifying Cored Wire Solder
Always a tricky one, in theory there is nothing in the solder wire that can go off so the expiration ...

Stagnant DI Water Usage
To be on the safe side I would exchange the columns for fresh ones, the whole idea of Ionic exchange ...

Lead to Hole Ratio for Lead Free
The hole to lead ratio subject has been covered a number of times in the past, generally due to the ...

Use of Nitrogen for Hand Soldering
Ultrasonic soldering has been used without flux for many years, this certainly works with Die attach how ever not sure ...

OSP Interval Times for Reflow
Normally as quick as possible. Without knowing your reflow profile it would be nearly impossible to give an accurate estimate. ...

Solder Hardness Comparison
As they have been run through the same process one would assume that they have both seen the same operating ...

Uneven Conformal Coating
It may be something as simple as the surface tension of your matte finish boards, The fact that you already ...

Circuit Board Exposed to Rain
One would have to ask first what the board is used for and how important its function is. The problem ...

Nano Coated Stencil Wear
Interesting question. The obvious problem with Nano coatings is that they are very thin. You are scraping a sharp metal ...

Opens at BGA Component Corner Balls
The most likely cause is probably warpage of the BGA Package, this seems to be the reason for the opens ...