Author: Elvis Howard

 

The Basics of Quick Turn PCB Assembly Process

Pcb-FabricationThe assembly of printed circuit boards is a multi-step process. It begins with the manufacturing of the substrate, followed by drilling and plating holes on the substrate surface, and then printing the circuit pattern on the substrate. After these first 3 basic steps, the contact fingers are attached then fused using a tin-lead coating. The panels are then sealed, stenciled and cut before the components are mounted on the PCB.

PCB assembly- Preparing the Substrate  

The substrate refers to the baseboard through which the rest of the PCB will be made. Substrates are often made from woven glass fiber. The glass fiber is impregnated with epoxy resin. The substrate is either sprayed or dipped in a vat of resin.
After impregnation, the glass fiber is passed through rollers to flatten it into the desired thickness. Excess resin is also removed as the substrate passes through the rollers.

The substrate is placed in an oven to semi-cure. After which, the substrate is cut into large panels. The panels are then stacked in layers. In between each glass fiber layer is a layer of copper foil with adhesive backings. The stacked panels are placed in presses under high temperature (340˚F/170˚C) and pressure (1500 psi) for at least about an hour. The resin is fully cured in this process and the copper adhesives are tightly bound to the substrate.

PCB assembly- Drilling, plating, printing

Several substrate panels are piled and pinned together for stability. The panel is then laid out to sketch a pattern. The panel stacks are placed inside a CNC machine where designated holes are to be drilled. After drilling, the holes are de-burred in order to remove any excess from the edges of the holes. Copper plating is placed on the inside surface of the holes, which will serve as conductive circuits. The non-conductive surfaces are plugged to prevent them from getting plated.

The circuit pattern is printed on the substrate either through a substractive or through additive process. In the subtractive process, the entire substrate surface is plated with copper. The pattern is then etched on the copper plating, removing copper on areas that are not part of the circuit design.

In the additive process, the surface is covered in foil, revealing only the areas where the copper plating is supposed to go in. The copper plating is only placed in the desired pattern and the rest of the substrate surface is left unplated.

PCB assembly- contact fingers

PCBContact fingers are responsible for the conduction in between the layers of glass fiber substrates. These are fastened to the substrate edge and connected to the printed circuit. These are then masked off for plating, using three kinds of metals, namely, tin-lead, nickel, and then gold.

The entire PCB surface with the circuit pattern printed with copper is coated with tin-lead. This coating material is very porous and easily oxidized. To protect the PCB from oxidation (rusting), the entire circuit board is passed through a hot oil bath or a “reflow” oven. The tin-lead coating is melted and allowed to reflow on the shiny surface of the PCB.

PCB assembly- Seal, Stencil and Cut

The panels are then sealed with epoxy. This will protect the printed circuit patterns from damage when the PCB components are being attached. Then, other instructions and markings are stenciled on the circuit boards.
After which, the panels are cut into the desired size of individual boards. After cutting, the edges are smoothed out.

PCB assembly- Mounting

Electronic components of the PCB are then mounted as the boards are passed through several machines. The panels are passed through an automatic solder paster if surface mount technology is used to mount the components.
After all the components are placed, the boards are packaged for storage and shipping.

Guide on Finding Appropriate Lanyards to Wear

Lanyards are among the supplies that the companies always have. Even probationary or permanent imagesemployees are entitled to have one. Maintenance and security personnel also have these straps for identification purposes. Stocks of these straps are being purchased to be given away for corporate branding and brand recognition in various events. But when it comes to purchasing supplies, knowing what type of lanyards to buy are essential because they come in different styles and types.

 

Consider the tips below to get an ideal lanyard :

 

Know the desired type and length

In choosing these straps, an individual should deal with the different styles available in the market today. The most common types are the round braided and the flat braided ones.

These are usually simple in design. For those seeking environment friendly supplies, there are eco-friendly types of straps that are usually made from bamboo or recycled plastics.
Are you looking for detachable ID badges? Then consider buying OptiBraid and OptiWeave type of straps.

These straps enable any pl3item to become detachable from the straps while still wearing them. Do you need to express support for a variety of causes such as cancer prevention and animal rights? There are awareness straps for purchase. For those who want to promote safety, the reflective straps available. For fashionably trendy individuals, there are creative beaded types as well as the imitation leather types.
The ideal length of straps is usually 36 inches, while the standard width’s around 3/8” to 5/8”.

 

Know the difference between breakaway and non-breakaway styles

Lanyards usually come in either one of these styles. It is typically safer to wear breakaways because if the strap is caught on something or pulled by someone, the clasp opens automatically so that the person wearing it won’t get hurt. With that in mind, it should be clear why it’s often recommended to buy the breakaway type if safety is a big workplace issue.

These breakaway clasps are ideal for use in secured facilities such as prisons and court houses.

They can be also used in schools and hospitals where there are higher chances of grabbing (done by students and patients).

 

Consider how the lanyard’s end was made

Finishing touches on strap’s end are typically done through beading, crimping or sewing. If a lanyard’s end is crimped, choose what’s best between a black oxide and a nickel-plated one.
Picture how badges and IDs can be attached. The two simplest types of attachments in straps are the hook and the split key ring. Other available attachment types include mobile phone hooks, swivel hooks, and bulldog clips. OptiBraid and OptiWeave types, as mentioned above, typically have their own cool options for attachment types.
There are other considerations to keep in mind when making lanyard purchases, especially when going for those customized variants. Apart from color, the graphics and texts are also of importance. One can also choose to print designs through silkscreen or dye sub imprinting. When opting to go with OptiBraid type of lanyards, one must choose between diamond and round sliders.3_129520_201316_promotional-lanayrds-LY-15005-1-inch-polyester-lanyard-with-engraved-bottle-opener_large

Definitely last but not the least, the cost should always matter. Go for both quality and quantity. Getting best quality (yet affordable) straps would mean they would be less likely to be replaced soon.
By keeping all these things in mind, shopping for a more appropriate strap to suit one’s company or personal lifestyle will be less difficult. Remember that this fancy item will introduce and represent the company’s name, so choosing wisely is important. Well, even if you’re aiming to use such laces for security purposes, you’ll still have to think thoroughly in every step of the way.

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