Bills of Material and Material Callouts

Bills of Material and Material Callouts

Material callouts

It can be incredibly helpful on a drawing to call out with a pointer where material should be used on the drawing.

 

  • Best practice is to callout items numbers on the physical layout, usually with a circled BOM item#.
  • This makes it much easier to identify which parts should be used together and where they should be used.
  • It’s also sometimes helpful to simply write part numbers directly next to items on a drawing.

 

 

 

 

 

 

 

 

 

Bills of Material

  • Best practice is to give a table with item numbers, those item numbers can be used for material callouts in the drawing.
  • Manufacturer part numbers for all components is ideal for all parts, except maybe where we stock generics like UL wire and heatshrink
  • We can certainly help with simplifying a BOM, but knowing exactly what materials we’re expected to use can be very helpful!

 

Cable Assembly

The First Article Process

The First Article Process is a crucial part of production requirements at Technical Cable Applications.  The process confirms that an assembly has been designed as intended and that documentation is complete and interpreted correctly.  It verifies that proper assembly techniques and tooling are used and assures that later builds of product are produced without variation.

Quotation

At TCA the first article process starts before an order is ever placed.  During the quote process the customer drawings or specifications are carefully reviewed.   This assures that all the elements for successful production are included.

The bill of materials is evaluated to make certain all the components shown on the drawing are called out and in the correct quantities.   They are looking for any obvious material conflicts such as wire size /terminal compatibility.  A mismatch like this could be because the insulation diameter or wire AWG is too large or too small for a terminal. Discrepancies like this could affect the integrity of the product or damage tooling.

The drawing is checked for clear dimensional criteria and for tolerances that are achievable for cable assemblies.   It is also reviewed for references to any documents or quality standards other than IPC.  If other quality documents are referenced Technical Cable Applications quotations specialists assure those documents are on file.

Tooling and Test Fixtures

During the quote process tooling requirements are checked for all the components.  At Technical Cable Applications the component manufacturers recommendations are checked to assure that the right tools are on hand.   It is verified that mating test fixtures are available for all connectors.  If either of the tooling or test fixtures are not on hand, they will need to be ordered for the build.

Work instructions

Work instructions are created by Technical Cable Applications production engineers.  These seasoned professionals have broad knowledge and training in cable assembly production and quality standards. For cable assemblies this would be to the IPC/WHMA -620B standard.  If there are other production or quality standards called out in the customer documentation the production engineers will obtain a copy and make sure they are part of the process.

The work instruction lists all the machines, tools, fixtures, and materials used.  It contains set up and programming instructions for any equipment used.

A Detailed Accounting

As the production engineers build the first article, they keep a detailed step by step accounting for every process used to build the assembly and in the order it is to be completed.    Special instructions and cautionary notes are often part of the instructions with detailed pictures for each step included.  The completed work instructions are controlled on a central server and every workstation has a computer terminal with to access the information.

In the event the production engineer finds any issue, conflict or has any concerns during the first article build the Sales Specialist is notified, the customer is contacted, and the concern and any resolution are documented.

Test and Inspection

Test and inspection steps are included in the work instruction including inspections where a process might be hidden by a subsequent step.

The finished first articles are sent to the Technical Cable Applications quality department where the assembly undergoes a series of dimensional and quality checks to assure that the assembly meets or exceeds the customer specifications.  The first article assemblies are tested and sent to packaging to be shipped with first article documentation to the customer.

Validation

Once the first article is inspected, tested, and approved by the customer the work instructions are validated by Technical Cable Applications quality personnel.  Production can then be scheduled for the assemblies.

Contact

Technical Cable Applications is an ISO9001:20015 registered company.  Please contact the Technical Cable Applications sales team for help with all of you cable assembly needs.

Drawing Cable Assemblies: Physical Layout

Creating a cable drawing that’s easy to understand and interpret can be pretty difficult, so here are a few pointers to help.

 

 

 

  • Right angles are easiest to interpret but not always necessary.
  • It should be clear where to measure dimensions from, like end of connector or back of connector (dimension lines are great!)
  • Dimensions should be measurable from places which can be measured on a completed assembly (wire cut lengths can be hard to inspect). We will 100% check these in final inspection.
  • Length tolerances should be wide enough to be easy to manufacture+/-5% is great. Use a -0 tolerance if nominal length is the shortest acceptable. (IPC has guidelines for this as well)

 

 

 

 

 

 

 

 

  • Labels and heatshrink should appear on the drawing with dimensions and tolerances (or specified as “about” or “TYP”)
  • Specifying the pinout of the connector, especially with colors, is very helpful. Best practice is 3rd angle projection of the connector face.

IPC Certification

TCA has a keen focus on the best possible product quality. Our assemblies are built and inspected to IPC/WHMA-A-620 standards as required by our customers.  This training covers requirements and acceptance for wire and cable harness assemblies. “These certification programs, built around IPC standards, developed and approved by industry, are delivered in a classroom setting by IPC certified trainers. As a non-profit, member-driven organization and leading source for industry standards, training, industry intelligence and public policy advocacy, IPC is THE global association that helps OEMs, EMS, PCB manufacturers and suppliers build electronics better. ” IPC Web site    TCA takes pride in delivering quality by focusing on standards based engineering and assembly.   



USB Cable Assemblies

USB cable assemblies are a cost-effective way to connect electronic devices. When first introduced, USB connectors and cable assemblies connected peripheral devices such as printers, scanners, cameras, and storage devices to computers. Now USB cable assemblies are everywhere and used for everything from programming systems in automobiles, connecting medical equipment, and charging cell phones for everyday use.

USB Assembly

Technical Cable Applications is your one stop shop for Off-The-Shelf USB cable assemblies. TCA offers a variety of USB 2 through USB 3.2 standard cables with various connector types in different lengths. Read More

Off-The-Shelf Cable Assemblies

Off-The-Shelf (OTS) cable assemblies are already made cable assemblies and wiring harnesses for a variety of standard applications.  There are tremendous advantages to purchasing off the shelf product.  Most notably are lower cost and immediate delivery.  Technical Cable Applications is best known for the custom cable assemblies and wiring harnesses produced in our Auburn, Washington facility.   TCA also offers a huge variety of Off-The Shelf cable assemblies that are in stock in warehouses throughout the country.

Read More

Cable Assemblies in Arizona

I mentioned in a previous post that TCA had expanded both here in Auburn, WA as well as the Southwest.  Formally, I’d like to introduce you to Jim Henderson who represents our Southwest business. Located just outside of Phoenix, AZ Jim comes with years of experience in structured cabling, wire harnesses and cable assemblies.  Jim is on the ground in Arizona and available to visit your facility for consultation and to review your requirements. He comes fully supported with a strong engineering team behind him available to help with costing, tooling, first articles, work instruction creation and eventually getting your assemblies into full scale production.  You can reach him immediately by calling our main line (253) 289-5572.

 

Custom USB Cables and Other Relics

One day I may just up and open up a museum dedicated to TCA antiquities.  Does anyone out there still have one of our original 2002 logo style hats? I can’t even begin to count how many variations of t-shirts, hats, pens, golfballs, catalogs, fliers or other paraphernalia we’ve had over 2 decades.  As we get closer to getting back into trade show mode, it’s fun to review our old displays made eons ago.  When our staff was less than 25% of what we are today, we were already pounding out more than 50,000 cat5e and cat6 network cables per month, all custom made to the inch.

 

We have custom display boards for all types of assemblies but what caught my eye today was the molded USB we created years ago.  Using a common base USB A connector from a trusted manufacturer we were able to build an overmold that created protection, strain relief, and not one but THREE exit holes.  This old display model may be showing some dust and age but the innovation is beautiful and what goes into it is still impressive to me. Multiple solder joints and splices lie under that tiny mold. I told you custom molds get me excited!