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Saturday 24 May 2014

The Versatility of The PCB Epoxy Repair Kit


The epoxy found in the BEST PCB epoxy repair kit has been proven useful for many different kinds of repair. It’s main use if for adhering or re-adhering pads and traces onto PCBs when they are lifted or need to be replaced. In addition, the epoxy has found use in the repair of damaged corners or repairing burnt out areas of the laminate as filler. By adding the proper colorant and by creating a “skim coat” for the outside surface of the repair, the PCB epoxy can be an effective replacement. Another use of the PCB epoxy is for mask replacement. Here again a little colorant plus the properly mixed epoxy will repair damaged solder mask areas.

green colorant for PCB repair
Green Colorant for PCB repair


The PCB epoxy comes convenient packed and premixed. Simply “burst” the barrier between the resin and hardner and mix it by moving it along the hard edge until it looks consistent.




Cut the tip off the bag and you can begin applying the epoxy.


PCB repair epoxy resin and hardner
PCB Repair Epoxy Resin and Hardner


Not only is this a versatile product but it has been a proven, reliable and effective material for 20 plus years having been used on tens of thousands of PCBs. There are a few published reliability and efficacy studies. There are many more company confidential studies that have been generated to prove the material is being effective in their end user environment including in leading cell phone, IT infrastructure and medical products.


Friday 25 April 2014

Different Types of SMT Stencils and Their Uses

By Bob Wettermann

There are a variety of different configurations of SMT stencils depending on the intended end usage. SMT stencils are used from prototyping a few boards to mass assembly of hundreds of thousands. Their usage and configurations are varied for a variety of reasons.

typical framed smt stencil
Typical Framed SMT Stencil

Prototype SMT stencils are used to build the first few assembled prototypes of the PCB or they may be used to prove out a concept of only a single function of a PCB. Typically the prototyping quantities are from a few pieces up to 50 pieces for mass volume assemblers. These SMT stencils tend to be “frameless” stencils in that they are held tautly to non-permanent frames. “Foil only” or “frameless” SMT prototype stencils are foils with the appropriate aperture patterns lining up to the locations on the PCB requiring solder paste. These foil only SMT stencils can be manufactured from either plastic (Kapton™) or nickel-based stainless steel alloys. Plastic stencils have limitations on the size of the apertures and the distances between apertures because the limited rigidity of the plastic is not as high of that of stainless steel.

Kapton™ smt stencil
Kapton™ SMT Stencil

In another derivative of this stencil “flaps” can be added to the sides of the metal SMT prototype stencils which will help limited solder paste flow to other areas of the PCB.

prototype smt stencil with flaps
Prototype SMT Stencil with Flaps

Another form of SMT stencils are frameless stencils. These are used when there are many board “spins” requiring lots of different stencils or when the PCB assembly area is space constrained. A single frame system has air pressure applied to the frame system and therefore creates the tension on the face of the stencil in order to create a quality print. These stencils are more cost effective than framed versions as the frame is eliminated and the shipping costs are reduced.

Finally, there are a variety of framed SMT stencil options which are fit to a given machine configuration. The frames provide the rigidity and the tensioning on the stencil. They come in a variety of different sizes and materials. Older stencil printing machines have cast steel frames while more modern stencil printing machines accommodate aluminum frames. Sometimes the SMT stencil frames are color-coded for a variety of reasons including identifying the alloy or solder paste versus adhesive versions.


Tuesday 11 March 2014

How to Reball Your BGA Using a Preform BGA Reballing Kit

By Bob Wettermann

There are cases when you need to quickly repair a BGA or CSP or POP package location. In removing the device there may be times where you would like to reball it and place it back onto the same location. In those cases you may night have the time to wait those few days for a customized reballing preform to the fit the package exactly. In those cases the BEST BGA reballing kit is the right tool/kit to have in your tool box.

BEST BGA Reballing Kit for Versatile Reballing Solution
BEST BGA Reballing Kit for Versatile Reballing Solution

By using this kit and some ingenuity when it comes to cutting, or some tape for blocking off or a few solder balls for adding at certain location many different new patterns can be made. This kit includes a variety of preforms at certain consistent patterns and pitches that allows you to do this.

Follow These Steps to Reball your BGA:


1. Deball and Prep Site Location. After the device is removed the remnant solder needs to removed. By using a soldering wick and hand soldering iron and some paste flux the remnant solder can be removed.

Apply paste flux to the BGA requiring to be cleaning up

apply paste flux
Apply paste flux

use braid and soldering iron to clean up site locations
Use Braid and Soldering Iron to Clean Up Site Locations

Clean up sites
Clean Up Sites

Inspect the BGA for any missing pads, scratched solder mask or any open connections that violate minimum electrical distance




2. Place preform ball side up on flat surface.

solder preform ball side up
Solder Preform Ball Side Up


3. Apply paste flux (water soluable preferred) to solder balls.

Apply paste flux to solder ball side of preform
Apply Paste Flux to Solder Ball Side of preform


4. Align and place BGA onto preform

align and place preform
Align and Place Preform


5. Put “sandwich” through the reflow process

6. Peel apart preform

7. Clean with water

8. Inspect

The process for reballing a single BGA once you get good at it is 5 or so minutes of labor assuming that no rework is performed. Once you get some proficiency at this process you should be yield 85% or better. The BEST BGA Reballing kit is your answer to your fast turnaround BGA reballing challenges.

Tuesday 4 February 2014

Effective Uses of Solder Training Kits


Solder training kits are used for a variety of reasons. The greatest reason these kits are purchased is for the purposes of training soldering technicians in the art of soldering. The second greatest use to for verifying the skill level of potential new hires in soldering and confirming their skill level. 

solder training kit
Solder Training Kit

Soldering technicians use solder training kits for training and certifying and re-certifying. If the soldering technician is IPC certified then a soldering kit will be used for the initial certification. This means that for either the IPC-J-STD-001 certification or for the IPC 7711/21 certification these soldering kits are used to verifying soldering skills for the instructor. After initial certification then once every 2 years these same soldering kits need to be used to re-certify the skill level of the technician. Internal certification programs wither based on the IPC program or not require solder training kits in order to verify the skills of the soldering techs as part of an internal training program.

IPC JSTD 001 lead free solder training kit
IPC JSTD 001 Lead Free Solder Training Kit



Wednesday 29 January 2014

Significance of Circuit Board Repair Kit


There are various kits available in the market for repairing PCB  otherwise known as the printed circuit board. In this article, we are describing the significance of circuit board repair kit that is widely used by electronics technicians. The kit consists of  a variety of tools and materials for the repair of both SMT and throughhole component locations. There are two methods of mounting the electronic items to PCB. The first and the most common method of attaching the components today is through the surface mounting process. In this process components are placed by a robot into printed solder paste located on pads on the PCB and then reflowed or melted.  

circuit board repair kit 


Thus, when the component is mounted in this fashion it is called a surface mount device. These components have flat contacts, short pins, leads or array of solder balls which enables attachment to the printed circuit board. In the second throughhole technique device leads are pulled through and soldering is done on the opposite or secondary side on which they are mounted. The assembly operation is much slower in this method, but it provides mechanically rigid connections and is done when components are massive or when the components will force applied to them such as a person connecting a cable.

A PCB repair kit is used when there is a PCB board physical defect and the assembly was already deployed in service or there was a defect induced in the manufacturing process. Generally, a circuit board repair kit is used when there is some of type of defect and the board may suffer from some physical damage. Thus, in case of such situation, the technicians need to repair the printed circuit board with the utmost excellence and accuracy. This can be done by using different kinds of soldering tools that are included in repair kit. Sometimes, repair kit manufacturing companies design their kit by using different kinds of assembling methods. When both throughhole and SMT parts are intermixed on a PCB it is know as a mixed technology board. Some manufacturers design and produce a circuit board repair kit for  mixed technology boards. 

The versatile circuit board repair kit includes all sorts of tools for repairing PCBs. They are used for solving or repairing a multitude physical damage of boards. The kit includes varieties of circuit traces, stencils and many other important components that are necessary for repairing the circuits. It has a variety of materials required for repair of solder mask and laminate. In addition to these materials, it also includes resin or harder epoxy for circuit replacement tasks of various tracks and pads. It also includes knives with a variety of blades for getting precise cutting amongst many other electric components.

Thus, if you are in need of circuit board repair kit, then you must rush procure such kits including all kinds of soldering tools.