Engineering Knowledge

Not all knowledge possesses the same character. Engineering Sovereignty recognizes four complementary forms, each with its own value and its own vulnerabilities. 

EXPLICIT KNOWLEDGE 

Documented. Structured. Searchable. Examples include schematics, drawings, procedures, manufacturing files, and technical standards. Explicit knowledge is the easiest to preserve—it can be written down, stored, and retrieved. Yet explicit knowledge alone is often insufficient. Documentation captures what was known at a particular moment, but it may not capture why decisions were made or what alternatives were considered.

TACIT KNOWLEDGE 

Personal experience accumulated through practice. Pattern recognition. Engineering intuition. Diagnostic judgment. Tacit knowledge is what enables an experienced engineer to diagnose a fault that eludes less experienced colleagues—not because they have more information, but because they have developed the ability to recognize patterns and interpret subtle clues. 

Tacit knowledge is often the first capability organizations lose when experienced engineers retire. It cannot be easily documented. It resides in the minds and hands of practitioners. Preserving tacit knowledge requires mentoring, apprenticeship, and the deliberate transfer of experience from one generation to the next. 

EMBEDDED KNOWLEDGE 

Knowledge incorporated into products themselves. Circuit layouts. Firmware architecture. Mechanical tolerances. Manufacturing techniques. The product becomes a silent teacher for those capable of interpreting it. Embedded knowledge is often invisible until it is needed—and then it may be the only surviving record of how something was designed or built. Recovering embedded knowledge is the essence of reverse engineering. The artifact itself contains clues about its design, its materials, and its manufacturing processes. Learning to read those clues is a core capability of sovereign engineering organizations. 

COLLECTIVE KNOWLEDGE 

Knowledge that exists within the interactions of engineering teams. Design reviews. Communities of practice. Lessons learned. Collaborative problem solving. Collective knowledge frequently exceeds the sum of individual expertise. It emerges from dialogue, debate, and shared experience. Collective knowledge is particularly vulnerable because it depends on relationships and interactions. When teams are disbanded, when experienced engineers leave, or when collaboration is replaced by isolation, collective knowledge dissipates. Building and maintaining communities of practice is therefore essential to preserving this form of knowledge. 

Engineering Sovereignty seeks to cultivate all four simultaneously. An organization that relies solely on explicit knowledge will find its documentation incomplete. An organization that values only tacit knowledge will lose capability when individuals retire. A balanced approach recognizes the unique value and vulnerability of each form. 

 

Why Engineering Sovereignty?

The term "Engineering Sovereignty" may sound ambitious, perhaps even grandiose. But it is a phrase born of necessity, reflecting a reality already being grappled with by governments, defense organizations, and industry leaders. Sovereignty has historically been a political and territorial concept. Today, however, its meaning is extending into the technological domain. 

An organization that cannot understand the technologies it depends on cannot truly control its own future. An organization that cannot regenerate its own engineering knowledge becomes a hostage to external suppliers, its fate determined by forces outside its walls. An organization that cannot sustain its critical technologies will see its operational readiness erode, no matter how advanced those technologies once were. 

Engineering Sovereignty, therefore, is not a synonym for reverse engineering. It is not simply a guide to remanufacturing, a blueprint for digital twins, or a manual for using AI. It is a far more profound and holistic concept. It is the disciplined, systematic cultivation of enduring engineering capability—the art and science of ensuring that an organization can think for itself, solve its own problems, and safeguard its own technological future.

 

Engineering Sovereignty

Three months ago, I had a meeting with two Singapore army representatives over coffee, discussing PCB-RE in the context of engineering expediency and operational capabilities. There was even the idea of a presentation to their top management, though it did not materialize in the end.

However, a seed has been sown since that meeting, and I have been quietly working on the framework of a discipline—Engineering Sovereignty. I wouldn't be surprise if many in the industry are not aware of this term. Most companies are more concerned about solving their immediate engineering problems than retaining valuable knowledge that is locked in the minds of their best engineers.

I'm not saying they lack sound practices in their organizational processes; but documenting technical designs of their products alone do not ensure that the know-how and experiences of their brilliant engineers, accummulated and built-up over the span of their career, are accurately and reliably passed on to the next generation. Personal legacy and skills can only be transmitted via mentoring and meticulous apprenticeship.

The Charter Seal above gives a concise definition on this concept of Engineering Sovereignty, and it is not only applicable to the military but commercial organizations as well. The first volume on this subject is near completion. I have kept it under wraps until now, while working in tandem with my Solutions on Obsolescence books, which were recently released. Although they belong to different series, they are related in regard to the challenges faced by many organizations today.

More will be revealed once the first draft of Volume 1 is ready. Until then, you may want to secure copies of the Solutions to Obsolescene books (click the book covers to go to the Amazon bookstore to order). 

Top Post

It may come as a surprise to my readers that the most popular post on this blog is not about PCB reverse engineering, but a suite of old EDA software that is now available for free, from a community of die-hard fans who are still using it.

That's right. It's the DOS-based OrCAD design tools (SDT, VST, PCB, PLD, and MOD). I believe many of us have used it at one time or another in a past era, when MS-DOS was still the only dorminant operating system available on the PC-AT running off an 80286/80386. With the advent of Windows, these DOS applications were relegated to the PC museum. Fortunately, DOS emulators like DOSBox and VirtualBox continue to give these valuable resources a new lease of life.

Those interested in OrCAD can click on this link to read and learn how to get a free copy. 

Release Announcement

I'm happy to announce the release of The Answer Book, a companion tutorial to the textbook, Solutions to Obsolescence: Remanufacturing, Retrofitting & Refurbishing. It is printed in full premium colors on better quality papers so the price will be slightly higher, but still affordable. I have paired these two books as a collection. You can read the book series description by clicking on this link.

To order these books, just click on their respective book covers displayed on the right column of this blog post, which will bring you to the Amazon website. As of now, Amazon still maintains the price of the textbook at the promotion price, but I'm not sure how long that offer will last. So grab a copy while you can.

 

About Me and My Works

I'm almost done with the Answer Book, a companion tutorial to the Solutions to Obsolescence book. I've included an About the Author write-up, which is really a description of my journey and what motivates me:

Hopefully, readers who are considering to take up the obsolescence challenge, or are already involved in such endeavors, will find the two-set volume useful. The Answer Book will likely be released by next week, barring any unforeseen circumstances.

Take care and stay safe, my friends.

Ps: The promotional price for Solutions to Obsolescence is ending soon. Please order your copy if you haven't done so. No request will be entertained after that.

Book Review Out of the Blue...

These days it's hard to find readers who appreciate my books enough to leave a nice review on Amazon. So I was presently delighted that someone left a glowing review for PCB Diagnostics which I've written about three years ago:

Excellent overview, really the only book of its kind. Getting back into advanced PCB diagnostics/repair having not worked in the industry for over 20 years, this book was a phenomenal refresher, so much so, I have several more of Mr. Ng's books awaiting to be read. 

I see another review complaining the book is full of expensive equipment, it does cover various things like A.T.E. and such systems, but also teaches the basics of diagnostics. I would say anyone coming to this book without sound electronics knowledge in the engineering realm will find themselves out of place with the material, but more so out of place if trying to do any such work. This book isn't for the part and board swappers looking for easy tricks that will fix PCBs, that is for youtube. If you really want to get into the field you need to hit the books and bench, use this as a guide for futher education.

If you, my reader and follower of this blog, have received the benefits of my hard-earned engineering insights and experience, would be kind to leave a good review on Amazon, it would definitely help in the ratings and sales to enable and motivate me to write more in the future. 

My wife, who supported me all these years in this gruelling work, always look forward to reading them, and find consolation that our efforts do make a difference and impact in other people's lives.

So have a heart and do your part. Hear from you soon! 

Repair, New, or Refurbished?

Question: 

Your plant has a 15-year-old conveyor motor that fails every 4 months. Each repair costs $300. A new motor costs $2,500. A refurbished motor (from a specialist) costs $1,200 with a 1-year warranty. Which path do you choose? What data would change your answer? 

Answer: 

Given: 15 years old, fails every 4 months → 3 failures/year × $300 = 900/year. New = $2,500; Refurbished = $1,200 with 1-year warranty. 

Simple payback (repair vs. refurbished): 

Current annual repair cost = $900.  
Refurbished cost $1,200.  
Payback = 1.33 years.  

After 1 year, warranty covers failures. From year 2 onward, assume refurbished failure rate is similar to current (3 failures/year) → another $900/year. Still cheaper than $2,500 for new. 

Decision: Choose refurbished motor based on current data. 

What data would change answer? 

▪ If the conveyor is a production bottleneck where downtime cost is >$500/hour → new motor (higher reliability) may be justified. 

▪ If the refurbisher's warranty excludes labor, adding $150/failure for installation → refurbished TCO rises. 

▪ If the motor is obsolete and refurbisher uses scavenged parts with unknown remaining life → avoid. 

▪ If new motor efficiency is 10% better, then electricity savings alone could favor new motor over 5+ years.

 

When to Choose Which?

Sample tutorial question and answer:

Question: 

Under what conditions would you recommend refurbishing over remanufacturing for a fleet of industrial power tools? 

Answer: 

Refurbishing is recommended over remanufacturing when: 

• The core structure and motor remain within original tolerances, but only wear items (brushes, switches, grips, bearings) need replacement. 

• Downtime is critical—refurbishing is faster because it avoids full disassembly to the last screw. 

• The tools are not yet discontinued by the OEM, so replacement parts are still standard. 

• The goal is cost containment with moderate extension of useful life (1-2 additional cycles), rather than bringing the tool to "like-new" performance. 

• The fleet is large and identical, allowing batch processing of common wear parts without requiring full rebuild of every subassembly.

 

STO Answer Book

Here's the book blurb I've crafted for the upcoming Answer Book, which is really a companion tutorial to Solutions to Obsolescence (STO):

The Answer Book is the companion every reader of Solutions to Obsolescence needs. It takes the 15 chapters of the main textbook and turns each set of discussion questions into a working session. You’ll find not just answers, but the reasoning pathways—the trade‑offs, the numbers, the risk calculations, and the contract clauses that separate a confident retrofit specialist from a hesitant one.

From TCO showdowns (new vs. refurbished lighting ballasts) to ethical dilemmas (third‑party remanufactured medical devices) to nitty‑gritty engineering (inertia ratios, thermal spray coatings, and VFD inrush currents), this book walks you through the decisions that obsolescence experts face daily.

Whether you’re a plant engineer, a remanufacturing line manager, a procurement professional, or a student of circular economy, the Answer Book will cement the concepts—and give you the scripts, formulas, and checklists to apply them immediately.

• TCO calculations for real-world decisions
• Root cause analysis for warranty returns
• Scripts for plant manager conversations

No fluff. No evasion. Just solutions. 

A Companion Book in the Works...

Readers who have recently purchase the book Solutions to Obsolescence would no doubt have noticed the discussion questions posed at the end of every chapter. Questions are a means to help readers understand and solidify what they have read. 

This is also a departure from my usual style of writing, since remanufacturing was new to me when I started out to learn the subject through researching and writing. It has tremendously enabled me to not just know how the three R's are interrelated to solving obsolescence, but also appreciate the dynamics between them in ways I did not preceive before.

Again, besides a visual aid like the book cover above, I will need a book blurb to help me focus on my writing. I anticipate that this will be a smaller workbook than the textbook, but it will no less be as informative and practical with many full-colored illustrations. I hope to finish and publish it in 3-4 weeks' time, if schedule allow.

So stay tune for more updates...

 

Release Announcement!

If you have been following the progress of my latest book writing attempt, you will be delighted to know that it has just been released and is available for order on Amazon KDP.

The book is currently available as paperback in full-color edition. It will also be available as hard cover in full-color, but because Amazon's hard cover does not support 8" x 10" format, I will need to adjust the manuscript to fit the nearest available size. This will take some time so if you can't wait, then order the paperback.

Printing in full-color is much more costly (3-4 times that of black on white), so I cannot sell at the normal low price like I did for the other engineering books. But I have kept the price as afforable as I can—for now as goodwill and promotion period, with a minimum royalty margin. So get this book as soon as you can. Click on the book cover to go to the Amazon order page.

The hard cover edition should be available in 3-4 weeks time but it will be more costly as I intend to use premium colors for this book format (first time trying). Still, I hope to keep the price below $100 (USD, of course).

That's all for the update, for now...

Ps: There will not be a Kindle ebook edition (at least not in the near foreseeable future).

The Final Lap...

I'm into the final lap of writing my seventh engineering book—the three R's of Solutions to Obsolescence. These include Appendices (Comparison Matrices, Glossary of Terms, and Strategy Selection Card), Acknowledgements, and a comprehensive Index for better reference.

I intend to just release a full-color, hard cover edition. It will not be as "affordable" as the other engineering books but I will keep the price below $100, if possible. Color printed books are not cheap to begin with, and for Amazon KDP it can come up to 3-4 times that of plain black and white print edition.

But I assure you, my readers, that it will be worth every cent to get a copy of this book when it is ready. The amount of work put in to ensure quality content and images are definitely not mesasured in dollars and cents.

I look forward to your support, through purchase and by word-of-mouth recommendations. It's been a grilling yet rewarding journey for the past couple of months. I believe there will be more engineering books to follow, if things work out for my collaborations with ASTER and the Singapore Army.

So stay tune for new updates.

Certifications as a Growth Accelerator

For remanufacturers seeking B2B customers (fleets, industrial plants, government), certifications are often mandatory, not optional. Certification, however, is a journey, not a one-time event. Start with ISO 9001, then add specialized certifications as your market demands. 

OEMs are increasingly entering remanufacturing—not as a threat to independents, but as a parallel channel. Here are two strategic advice for independents:  

▪ Specialize in products OEMs ignore (low-volume, obsolete, industrial).  

▪ Build capabilities OEMs lack (reverse engineering, restoration of non-supported components).

 

Scaling Remanufacturing

A remanufacturer can succeed as a small shop: one technician, a parts washer, a test stand, and a loyal local customer base. Many do. 

But remanufacturing's full potential—the ability to compete with new products at scale, to offer national warranties, to supply OEMs themselves—requires scaling. 

Scaling remanufacturing is not simply doing more of the same. It requires: 

▪ Facility design for workflow efficiency 
▪ Automation where labor costs dominate 
▪ Quality systems that survive volume growth 
▪ Certifications that signal credibility 
▪ Market acceptance strategies that overcome the "used product" stigma

Unlike manufacturing (raw materials in, finished goods out), remanufacturing has a variable flow. Cores arrive with unknown quality. Some move quickly; others require rework or wait for parts. It is therefore imperative to have a facility that is designed for remanufacturing workflow. (see figure above)

 

Reverse Engineering and Additive Manufacturing

When parts cannot be sourced or restored, the remanufacturer must create them. This is accomplished via reverse engineering and additive manufacturing. The processes can be quite involved, requiring multi-disciplined skills and specific equipment. It is not a one-man effort but a team of competent engineers and technicians who know their trade and tools. 

Reverse Engineering Example – Obsolete Bracket:

Part: Mounting bracket for alternator on 1990s diesel engine
Availability: OEM discontinued, no aftermarket 
Sample: Worn bracket from donor core
Measurement method: 3D scanner + CMM verification 
Material: Cast aluminum (identified via spectrometer) 
Manufacturing method: CNC machined from billet (no casting tooling cost)
Cost per part (10 units): $45 each (vs. OEM new was $18—but unavailable) 
Outcome: Bracket reproduced. Remanufacturing continues.

Of course, reverse engineering occupies a legal gray area. Remanufacturers must navigate intellectual property (IP) law carefully.

The Parts Availability Crisis

The core promise of remanufacturing is to extend product life indefinitely.  

But there is a catch— 

▪ What happens when the original manufacturer no longer makes the parts you need?  
▪ What happens when the product is 30 years old and the OEM has discontinued support?  
▪ What happens when the company itself is out of business? 

Without parts, remanufacturing stalls. A perfectly restorable core—sound housing, restorable shaft, reusable frame—becomes scrap because a $5 seal or a $50 bearing is no longer available. 

We need to address the parts supply challenge that defines the difference between remanufacturers who survive and those who fade away. This covers: 

▪ Sourcing existing parts (OEM, aftermarket, donor cores) 
▪ Reverse engineering obsolete components 
▪ Additive manufacturing (3D printing) for remanufacturing 
▪ Restoring parts that cannot be sourced (remanufacturing components themselves) 
▪ Legal and intellectual property considerations

 

Inspection and Sorting

This is the most critical quality control stage in the remanufacturing workflow. Every component is inspected—no sampling, no assumptions.

Sorting Decision Tree 

For each component after inspection, we need to ask: 

Is it within OEM new specification? 

• Yes → Clean, protect, move to reassembly 
• No  → Is it restorable (machining, coating, grinding)? 

        • Yes → Route to restoration (Stage 5) 
        • No  → Is a new replacement available?  

                • Yes → Source new part 
                • No  → Scrap component (mark as unusable) 

The inspection stage drives the entire remanufacturing process. Every component is sorted into one of four paths: reuse, restore, replace, or scrap.

 

Remanufacturing Workflow

Remanufacturing is the most process-intensive of the three strategies covered in this book. Unlike refurbishing (partial disassembly) or retrofitting (add-on modifications), remanufacturing requires complete disassembly, 100% inspection, systematic restoration, and full performance testing. 

The workflow presented here is generic—applicable to automotive engines, industrial gearboxes, heavy equipment components, and beyond. Specific industries will have variations, but the core logic is universal. 

The Seven Stages of Remanufacturing: 

1. Core Acquisition and Intake – Sourcing and grading used products 

2. Complete Disassembly – Down to the last component 

3. Cleaning – Multiple methods, multiple passes 

4. Inspection and Sorting – 100% dimensional and nondestructive testing 

5. Restoration and Replacement – Machining, coating, new parts 

6. Reassembly – To OEM specifications, with new wear items 

7. Testing and Certification – Full performance validation

The Mindset of Remanufacturing

Remanufacturing is not just a set of processes. It is a mindset. Five principles distinguish true remanufacturing from lesser imitations. 

Principle 1: Assume Nothing 

The repair technician assumes a component is good until proven otherwise. The remanufacturer assumes a component is bad until proven good.

Principle 2: Wear Items Are Always Replaced 

Certain components have finite lifespans: bearings, seals, gaskets, brushes, filters, belts. Even if they appear functional, they have consumed part of their design life.

Principle 3: Restore, Don't Just Replace (When Economical) 

Some components (housings, shafts, blocks) are expensive to replace but can be restored to original tolerances through machining, grinding, thermal spray coating, or other processes.

Principle 4: Test to New-Product Standards 

A remanufactured product must perform identically to a new product under the same test conditions.

Principle 5: Warranty Parity 

A remanufactured product without a new-product warranty is not truly remanufactured. It is something less—rebuilt, reconditioned, or refurbished—regardless of what the marketing says.

Remanufacturing is not equally applicable to all products. It thrives where: 

• The core has high intrinsic value (e.g., cast iron block, precision-ground shaft) 
• Wear items are modular and replaceable 
• The product is designed for disassembly (or can be disassembled with reasonable effort) 
• New replacement cost is high 
• Customers value reliability and warranty 

Reman: The Gold Standard

Remanufacturing sits at the apex of the three strategies for several reasons. 

Reason 1: Reliability 

A refurbished product is a gamble. It might last years; it might fail next month. A remanufactured product carries the same statistical reliability as a new product—because it has been restored to the same tolerances and specifications. 

Reason 2: Warranty Parity 

Customers who buy new products expect warranties measured in years, not months. Remanufactured products can offer those warranties because the restoration process is comprehensive enough to justify the confidence. 

Reason 3: Environmental Impact 

Remanufacturing saves 80-95% of the energy, water, and raw materials required to manufacture a new product—because the core (the housing, the block, the frame) is preserved. Only wear items are replaced.

Reason 4: Economic Value 

A remanufactured product typically sells for 40-70% of the new price, with gross margins that are often higher than new (because the core is acquired at low cost and the labor-intensive restoration is still cheaper than virgin materials and new component fabrication). 

A customer who pays for a remanufactured product expects new reliability. A rebuilt or reconditioned product will not deliver that. Engineers specifying remanufacturing for safety-critical or high-reliability applications must ensure they are getting true remanufacturing—not a cheaper imitation.  

The Gold Standard?

No, I'm not talking about the precious metal that people the world over looks to as the standard for guarantee, security and stability in the current economic downturn. I'm talking about remanufacturing.

Let's recap the first two strategies for combating obsolescence:

• Refurbishing restores function and appearance but leaves most components original. It is a facelift—valuable, cost-effective, but not a reset. 

• Retrofitting adds new capabilities to old platforms but leaves the core systems untouched. It is an upgrade—powerful, but narrow in scope. 

Remanufacturing is different. It is total. It is complete. It is the closest thing engineering has to a resurrection. 

Remanufacturing takes a used product, disassembles it completely to its core components, cleans and inspects every part, replaces or restores every wear item, and reassembles the product to original (or improved) specifications. The result is indistinguishable from new—and often carries the same warranty.

In other words, remanufacturing is total transformation. Nothing is assumed to be good enough. Every component is inspected, and every wear item is replaced. Period.

Ps: Incidentally, my fourth book Manual PCB-RE: The Essentials, has been dubbed "The Gold Standard" by an Amazon reader.

Remanufacturing (Revisited)

In late March, I was contacted by the DGM of ASTER and was invited to tour their facilities in early April. Then, sometime early June, a representative from the Army sought me out via Facebook Messenger and arrange for a meetup with his superior in the middle of the month.

Was it coincidence that two organizations, one commercial and the other military, expressed interests in my niche skillset of PCB reverse engineering? All within the space of two months this year. Both are also involved in remanufacturing, albeit in their own operational capacities. The timing could not have been anticipated.

After ten years and six engineering books on PCB-RE and its related subjects, I couldn't believe that here, locally in Singapore, there are actually people who not only read my works but also actively practicing this craft. I was both consolated and excited! It has opened new opportunities for future collaborations as well as enhancing local expertise.

Now that I have drafted two out of the three Rs (Refurbishing and Retrofitting) of Solutions to Obsolescnce, perhaps it's time to work on the final R (Remanufacturing).

Ps: Overseas readers and professionals who have read my book or are involved in these three aspects of overcoming obsolescence, do comment on this post and give your views.  They may prove invaluable to the upcoming book I'm currently working on...

Economic Modeling

After all the technical assessments—voltage, protocols, inertia, safety—one question remains. 

"Does this retrofit make financial sense?" 

Engineers often treat economics as someone else's problem. That is a mistake. The engineer who can build a credible economic model is the engineer who gets projects approved. The reason is obvious: Economics is not the only driver for retrofits, but it is almost always the first question asked.

For that, we need the tools to answer the following questions with rigor: 

▪ How do we calculate simple payback and return on investment (ROI)? 

▪ How can we model energy savings (the most common retrofit driver)? 

▪ How to account for productivity gains, maintenance reductions, and avoided downtime? 

▪ How do we handle uncertainty and risk in economic models? 

▪ How can we navigate incentives, grants, and carbon accounting?

In the upcoming book: Solutions to Obsolescence, I will try to address these questions and more. 

The Five Compatibility Domains

A retrofit that works is a triumph of engineering efficiency. A retrofit that fails—spectacularly or subtly—is a reminder that old and new systems do not always play well together. The difference is risk assessment performed before the first wire is cut. 

A systematic framework for identifying, evaluating, and mitigating the technical risks of retrofitting is therefore essential. It covers the five critical compatibility domains where old and new systems interact, namely: 

1. Electrical (voltage, current, power quality) 
2. Signal and protocol (communications) 
3. Physical (space, mounting, thermal) 
4. Mechanical (loads, dynamics, wear)
5. Safety (risk migration, integrity levels)

The Venn diagram above provides a visual representation of the five domains in their overlapping relationships. For each domain, the three areas of concern are failure modes, assessment methods, and mitigation strategies.