When it comes to repairing lifted pads you will realize that there’re two main industry-accepted methods of in case the main objective is replacing the pad. The first method involves using curable adhesive of high pressure and dry fil heat which you will stick in your replacement pad. The other way involves using two-part epoxy so that you can glue the replacement pad tightly to the laminate.
Epoxy repair method involves repairing pads using a two-part epoxy adhesive system and replacement plated pad. For you to undertake this method you must clean the pad properly for it adhere well with the repair equipment. You must also inspect all the tools so that you can do the procedure properly. To begin this process, you will have to remove the pad using a knife and cut a small part of the connecting circuit.
Replacement of pads which have a commercial circuit frame.
Use flux and proper solder so that you can attach the replacement pad to the connecting circuit through lap soldering them together. To do this you will have to follow the procedure below:
- Mixing the two-part epoxy according to the instructions given by the manufacturer.
- Directing the mixture to the target part.
- Applying pressure to your replacement pad.
- Laminating and curing the pad according to the instructions given by the manufacturer.
What you should know is that this method can also work to attached and lifted pads. It’s therefore, important that you inspect the anomalies so that you can perform the test of electrical continuity( post repair chest).
The other repair method involves using plated replacement pad which is dry film backed so that it’s adhered to PCB laminate through pressure and heat activated dry film. There steps which are using in the epoxy method to also apply here up to where you will be required to select the repair material. After looking at the circuit frame and identifying the replacement pad, you will use a sharp blade to cut it out of the frame. In this scenario, an expert will ensure that he/she cuts through the replacement pad and the adhesive backing. After that, the pad will be soldered to the traced as required.
Replacement pad which is held using Kapton tape for resin or epoxy curing process.
In this case, handheld heating equipment that’s similar to a soldering iron will be placed into a fixture which controls the downward pressure. The adhesive will be able to cure through the tip pressure and heated tip temperature. The other remaining steps are usually similar the ones of the epoxy repair.
One the kinds of pad repair which are difficult to handle are the ones which have embedded vias. The main reason for this is that when they’re connected to other types of board layers, they will still require to maintain the connectivity to the connected layer after the repair process. There’re so many ways to maintaining many of these challenging repairs such as jumper wires for the trace interconnections of small copper.
Finally, as seen above you will realize that there’re two ways which can be used to repair damaged pads. These methods are the dry film and two-part resin/epoxy. By contacting a highly trained and skilled technician he/she will be able to assist you in any of these repairs if the reliability risks have been mitigated.