web counter

Tolerances, Ridiculous Tolerances and Getting the Job Done

May 27, 2017


We serve a terrific east coast manufacturer of OEM transducers and custom strain gauges and load cells. We provide them with machined parts, printed circuit boards, wiring harnesses, sheet metal enclosures and other specialized hardware.

Many of the machined parts display unusual geometries, require highly specialized surface preparation, electroplating and coatings and call out exotic alloys. As our customer is a job shop, their orders tend to arrive without any notice, are varied and range from a handful to no more then 1500 pieces.

We recently quoted a familiar looking part that we call “hydrants”. Cylindrical base, a slim blade or “neck” and a smaller circular “head and shoulders. It’s one of a family of related transducer bodies machined out of aluminum and steel. This particular part specified a +/-0.0005 inch parallelism tolerance on the neck.

We took exception to the tolerance, politely pointing out that all of the other related parts specified only a +/-0.005 inch (WITP = “walk in the park”) tolerance. We asked both why the super tight tolerance was needed as well if we could have some relief. Without relief, this was going to be a “no quote”.

The initial response was a simple “no, we need it as it’s specified on the drawing”. So, we pushed back and asked our customer again. They asked their customer. And finally that customer asked the end user. After more then a month of back and forth, we got:

“In order to avoid stopping the manufacturing process of the transducer bodies and open POs, please ask your machinist to manufacture the next batch as usual and collect data (at least thirty measurements) on the parallelism. This exercise will give us a better idea of your capability to meet
+/-0.0005”. Based on the results we both can make the call on revising the parallelism spec.”

Now, please allow me to offer this translation of their comments:
“Tom signed off on the drawing in 2013, but he doesn’t work here anymore. The part sure looks like all of the others. It was probably just a typo and the tight tolerance isn’t really necessary. Regardless, we need a paper trail and this exercise to cover our backsides.”
One other point worth mentioning: due to the part geometry, almost no metrology lab can measure parallelism to that level of acuity.
So, we manufactured the parts, collected the data, yielded a parallelism of +/-0.0007” and the customer declared victory. And the parts worked like all of the others and we all got the job done.
The moral to this story is that while some tolerances are “must have” many are “nice to have”. If your vendor pushes back, please try to meet in the middle with a “kinda must have” solution.


Jack Daniels

Look Easy To You?

April 27, 2017


Please take look at the photograph below. It shows a sample of an elastic cord with a “lamb knitted” polyester and Spandex cover. Our customer asked us to develop a supply of the cord and then fabricate small loops that are incorporated into a “single use” or disposable medical device.

Looks simple, right? How complicated can it be to develop some stretchy cord? Well… Pretty darn complicated.

While our customer provided a drawing that defined the basics such as the cord diameter, length and elongation (50%), other elements such as color (white, exactly how white, which white?), basis weight (grams/meter), Young’s modulus (the amount of force required to stretch the cord over a fixed distance) and the composition and style of the knitted cover (the number of textile stitches per inch or the density of the knitted yarns) weren’t called out.

When we pressed our customer, they said “we want it exactly like we’re getting it now”.

We face this situation every day. Our customer knows what he or she wants (“make it so it works in my device”) however the details aren’t clearly or completely stated. There’s a specification, but it’s not written anywhere. Rather it’s more implied or coded into a model, a prototype or the designer’s head.

We sometimes receive a drawing, a product requirements document (PRD) and if we’re fortunate, a sample. Those elements along with our discussions with the customer help us to tease out a specification that allows us to define the product. But it’s not a straight path to the goal line.

In the case of the elastic cord, we were able to draft a PRD that minimized the ambiguity and defined the intangibles around two key properties. The “feel” or “hand” for the knitted cover was very important to the users as well as the “snap back” or Young’s modulus. In order to do this, we needed to build four generations of cord samples, supplied by two vendors, fabricate loops and build them into finished products that were evaluated by the product management team.

The take away from this is that products that are uncomplicated in appearance aren’t necessarily simple once you get under the skin. When you’re going out to generate a quotation and develop a supplier, the investment in time to pin down as many variables as possible will pay dividends.


Jack Daniels

Eight Steps to Manufacturing & Production Success

March 27, 2017

Depending on the complexity of the product, we prefer to begin to work closely with our clients and the design team when the project is on the “fifty yard line”. At this point, the fundamental engineering is complete, we’ve moved past pencil sketches and a basic BOM has been defined.
After reviewing the emerging design package, we can influence or change some of the design features and recommend small “tweaks” to improve “manufacturability”. This process involves:

  • • Developing an understanding of the product’s design/technology, estimated annual usage (EAU) and target price.
  • • Pinning down any regulatory, international standard or compliance requirements. This can include UL certification, FDA approval, CSA testing or CPSIA examination.
  • • Understanding the timing of the project (when the finished goods must land on the dock) and crafting a feasible time line with achievable milestones and build in some schedule slippage.
  • • Defining the components, materials, sub-assemblies, packaging, etc. and qualifying suppliers.
  • • Pinning down the specifications for critical elements in the BOM, including colors, surface finishes, mechanical tolerances, electrical performance, testing requirements, etc.
  • • Craft a budget for molds, jigs and fixtures and a schedule to build and validate the tooling including first article inspection (FAI).
  • • Pre-qualify candidate vendors and put the project out to bid. Review the bids, explore and qualify requested technical exceptions and finalize the vendor.

All of this information is collected in a PMF – our Project Management File. Our collective thoughts, changes to design, component and material selection, tooling changes, process definitions, test results and stakeholder feedback is recorded in one document that can be passed amongst all of the players to keep everyone on target.
And where’s the eighth step? It’s a might big one and it involves building models, carrying out preproduction engineering runs, running limited or “shakedown” production and then guiding the transition into full on production… Number 8 deserves its own list. More next month.


Jack Daniels

The Hand-Off from Initial Product Concept to Design

February 21, 2017


I was just talking with our good friend and frequent collaborator Jim Pelletier at Angle Development (www.angledevelopment.com). Jim runs a boutique product development firm based in Boston. Their foundation is deep knowledge of mechanical engineering with a strong dose of industrial design flair. They do beautiful work and their “turnover packages” make our job much easier.

What prompted our discussion was the challenge we face when deciding when it’s time to “jump in” to a new hardware project. While we know intuitively when it’s too early for EastBridge (“we have a pencil sketch and made a scale model out of cardboard”) I wanted o explore when the design team should launch.

Jim feels that in order to step off on the right foot, the following guidelines/checklist may prove useful to complete before you reach out to your development team.

You should come to the developer with a good idea of what their product “is” and “does”. This involves:

  • • An understanding of the market segment(s) their product belongs within (even if they’re pushing the boundaries of this market).
  • • A sense of who their customers are (demographics, abilities, intelligence, unmet needs/desires that the product will fulfill).
  • • A proven-feasible core technology for the product (*).
  • • An (at least rough) idea of what features and functions of the product will include.
  • • How their users might use/interact with the product.
  • • Consideration for the safety of the user, other stakeholders/bystanders, the environment.
  • • An understanding of all applicable regulations/testing/certifications required for the product (in all intended markets).
  • • A basic marketing/sales strategy (including a target cost-of-goods and project time line)

These would generally be communicated through a product requirements document (or PRD), a functional prototype or other embodiment of the core technology, and a project plan. None of these would need to be “set in stone”, as they will all invariably change as the project progresses. However, a good developer won’t be able to propose a decent product development process without these items.

(*) The assumption here is that the design team generally doesn’t engage in basic R&D or core technology development. However, depending on the type of product, a skilled design team may be able to make suggestions for resources that specialize in the earlier phase of the overarching process.

All logical and good stuff. Next month, we’ll highlight what your manufacturing resource needs for a smooth hand off from the design team.

Jack Daniels

From Giant Factories to Family Workshops: Suppliers of Every Size

December 14, 2016



When we’re setting off to make a new hardware device, one of the first steps involves assessing the key technical domains represented in the build. Printed circuit board assemblies (PCBAs), membrane switches, formed & machined metal parts, wire & cable and molded plastics, etc. can all be wrapped up in one device.

Our strategy in identifying a supplier that’s a good fit directs us to select a CM that has more than one manufacturing competence. A factory that’s as close to vertically integrated as possible.

An example is a box build factory that can stuff PCBs, build cable harnesses and stamp out sheet metal enclosures. This class of supplier will be better suited and lower cost than a “screwdriver factory” that purchases every component and sub assembly and simply screws the box together.

While total vertical integration is a terrific goal, it never happens for anything more sophisticated than gases… Never. Ever. Factories large and small have complex supply chains that they must rely on. As a result, you also must rely on their network of suppliers.

The complexity or number of degrees of separation contained in a typical supply chain is astonishing. If you consider something as “simple” as a deep drawn aluminum shell to be used in a consumer product, there are more than twelve suppliers that can be identified that directly effect the product quality: the metals distributor, the tool & die shop that fabricated the deep draw tooling; the centerless grinding subcontractor; the vendor that laser scribes the logo on the shell; the anodizing subcontractor; the pigment factory that supplies the anodizer; the packaging supplier; the laboratory that certifies that the finished shell doesn’t contain heavy metals… It goes on and on.

A multi-layered supply chain requires an enormous amount of planning and due diligence on our part. For high risk products, we need to go “upstream” to carry out due diligence on key components, materials, sub assemblies and processes. This can take us four or five levels and multiple branches up the chain. For lower risk components, we need to verify two to three levels and branches.

Regardless of the geography where we’re working, some upstream suppliers will be small (sometimes very small) and humble in appearance. This doesn’t mean that they’re not very good at what they do – they’re just not architectural showplaces and they may be a bit difficult to communicate or trade with.

So once the principal CM is identified, we dig in and confirm the capability of their vendors and sub vendors. We think that this is good business and worth the time and effort.


Jack Daniels


Six Key Points To Remember When Buying Tooling

November 13, 2016




When you’re developing a new hardware product, once you get past the prototype and proof of concept stage, chances are you’ll need to buy some form of tooling. Be it injection molded plastics, die cast metal, metal injection molded (MIM) or blanked & stamped parts, at some point, you’ll need to commit to custom tooling.

While there are several baby steps that you can take before ordering production tooling (“soft” tools such as cast silicone or urethane and slush molding, aluminum & mild steel single cavity molds, 3D printing, etc.) once you’ve pinned down the design, it’s time to order real tools.

When we order and buy tools, we follow a checklist that was developed after many years and a few misadventures. It’s summarized below:

1. Project Scope

Consider the production requirements of your project: number of units to be ordered in Year 1, 2 and 3; appropriate number of tools and cavities; press capacity/capability of the molder (can they scale to a larger multi-cavity mold as your volume grows or add additional tools on smaller presses to keep up with the demand?); as your design evolves and product extensions are introduced, are options such as inserts, over molding and in-mold decoration, assembly available?

You should partner with a molder that’s flexible and can grow with you. If you can avoid moving the tools, you should.

2. Triple Quote the Tools

While this seems obvious and a basic tactic of procurement, it’s surprising how many companies reflexively single quote their “go-to” molding vendor.

Don’t do it! While it’s important to have multiple quotes for any project, it’s more critical when your parts require a specialized mold. There’s a lot of variation in tooling production techniques which impacts pricing. This is magnified when the molder uses a third party tooling vendor to make the molds (more on this below).

3. Mold Flow Analysis

We perform design reviews on all of our clients’ new designs and then carry out mold flow analysis. This allows us to predict the appearance and quality of the finished parts before pulling the trigger and ordering this molds. It also helps us to maintain their design integrity. Further, it gives us the opportunity to recommend small changes (“Can we change this radius a couple of degrees? It will reduce the cost of the tool by $7800.00…”) that save time and money.

4. Mold Specifications

Consider the grade of steel and finishing operations (hardness and surface finish) called out on the tooling quote. Those variables help to define the and number of shots (yield of molded parts before the tool needs to be retired) and the quality of the finished parts.

Related to this, what’s called out for mold & part validation? Can you send your representative to the factory to conduct mold trials? How many “Tool Grooms” (T-0, T-1, T-2, etc) are included without triggering an additional charge? And what is the number of complimentary samples included in the trial?

5. Allow Sufficient Time

Everyone is rushed. There’s never enough time – we know this. Complex tools take a minimum of four weeks and often six weeks to turn. If a vendor quotes two weeks, find a new one.

6. Commercial Language in the Contract

Reasonable tooling vendors will request a down payment of 50% with the balance being paid upon your approval of the tool and parts. Unreasonable vendors want a much larger down payment or total payment up front.

Other elements of the tooling contract focus on the life of the tool (number of shots) and often replacing the tool gratis once you’ve achieved some “parts purchased” threshold. Other language defines who actually owns the molds. It should be you – it generally doesn’t work in your favor to amortize the cost of the tools in the finished part price. You should be guaranteed the right to “pull” or transfer the molds to a different vendor, with some reasonable notice. And if the molder is outsourcing the tooling generation to a third party, this should be clearly defined.

We’ve crafted a tooling agreement (it’s bilingual Chinese-English, especially helpful in Asia) that clearly lays out the conditions that we’ve learned is advantageous for our clients. You can find it by following this link:


[Please don’t construe this as legal advice… You’re free to use it and you’re also free not to use it.]

Purchasing tooling shouldn’t be a trial (though it should include a mold trial). Follow our checklist for a more predictable and profitable experience.


Jack Daniels



Product Inspection Checklist: Eight Steps to Success

July 21, 2016


We routinely carry out WIP (Work in Process) and final inspection of complex products for our customers. For the WIP, working with our suppliers, customers and our team of Supplier Quality Engineers, we determine the optimal time(s) to inspect the products during production. It’s usually much easier to measure performance of key subsystems and components before the unit is fully assembled and “in the can.”

Inspections at this stage allow us to have confidence that the quality is “baked in” to the product during assembly.

Final inspections usually take place before “pick, pack and ship” and provide the opportunity to monitor product performance, cosmetic standards, fit and finish and compliance with all specifications. This inspection stage often involves taking the product through the paces of performance – running through all of the steps in the user’s manual, examining the packaging, doing a tear down on a small number of units and assuring that the user experience will be what the design team intended.

Occasionally, our customers require EastBridge to step up and (usually quickly) inspect products at a factory that’s new to us. In order to do a useful job, we need the following:

  • Name and address of the factory plus the name, email address and mobile number of your contact person there
  • General description of the product
  • Specifications, inspection standards, drawings, etc. for the product, accessories and packaging
  • A list of critical, major and minor dimensions or appearance criteria
  • The AQL
  • A “golden sample” or reference standard
  • The size of the lot to be inspected.
  • Any special requirements

If you can share this information, plus at least a few hours of notice, we can be efficient, helpful and you can confident in the quality of the goods that you’ve purchased.


Jack Daniels

Source Development – The EastBridge Process

June 16, 2016


Not to stretch the creation metaphor too far, when a new or redesigned product is conceived, is in gestation and and is about to spring forth, it pays to have and experienced midwife in the mix. We frequently hear that EastBridge is just that – the midwife who guides the birth of new products.

When you get down to it, we’re in the business of landing (birthing) fairly priced and top quality custom products on the docks of our customers. There are many steps (and countless phone calls, meetings, design reviews, BOM development, mold-flow analyses, material testing and email notes) before we arrive at that point and a lot to juggle.

In order for the “baby” arrive healthy and on time, we follow a process that’s tried and true. The checklist that guides each of our projects is summarized below:


Phase I:

General Specification Review

Pre qualification of approximately three (3) contract manufacturers (CMs) and a corps of supporting subcontractors

Execute customer/vendor mutual non disclosure agreement (NDA)

On-site factory audit of the candidate vendors

Confirmation of the specification & generation of budgetary quotations, FOB term

Estimated Duration: Four Weeks

Phase II:

Specification refinement and confirmation

Sample generation/trial run (tooling build, FAI, etc.)

Secondary pricing & commercial terms negotiation

Finalize vendor(s)

Design for manufacturing & assembly (DFMA) and process optimization

Estimated Duration: Twenty Weeks


Place initial order on behalf of the customer by transmitting customer’s PO to the vendor(s),

Expedite the order and advise the customer of the delivery schedule

Perform work in process inspection (WIP)

Perform inspection of the finished goods

Supervision of all shipments

Shipment coordination, administration & translation.

Estimated Duration: Ten Weeks

Now while the timing shown for each phase differs from project to project, the overall process and trajectory for complex products is defined by this checklist. With or without us, it’s a lot to keep track of… We think that the EastBridge process is helpful and hope that you will as well.


Jack Daniels

When You Reupholster a Sofa, Start With the Couch…

March 21, 2016


We’re in discussions with an early stage consumer products company. They want to “re-skin” an existing small electric appliance. Re-skinning involves creating a new “skin” or plastic enclosure or shell for an off-the-shelf device.

We’ve done this many times and it represents a product development model at the intersection of the ODM/OEM universe. The buyer isn’t simply re-branding (by changing the imprinted logo or packaging) a current product made for the mass market, but rather they’re leveraging the “bones” (sometimes referred to the “chassis” or “guts”) of a product that’s in production.

This is a useful strategy to introduce a somewhat new product with a customized appearance, without going through a complete ground-up redesign.

All good: the process starts with searching for products that have the required attributes or properties. Physical dimensions, power level, feature location and usability, etc. Once we’ve purchased samples, performed the tear down, recorded the chassis dimensions and variables, the next step is for the industrial designers and mechanical engineering team to create a new skin to cover the bones.

Not all good: start with creating renderings and sketches of the desired skin, throwing them over the wall to us and asking that we find a device that “fits”.

Sorry, but this is bassackwards… We can’t shoehorn an existing chassis into a new shell with any expectation that it will fit or work. And we really can’t gauge how much it will cost. With zero confidence in the process, we can’t even SWAG a cost for the tooling.

This is not a good approach. When trying to explain why, we came upon the upholstery example. We can talk endlessly about fabric, stitches per inch, ruffles, wooden feet, etc. We certainly can’t even guess at how much fabric to buy, how we’ll attach it to the frame, how long it will take and if it will meet flammability standards.

So – if you’re planning on re-skinning a small electric device, please start with the device.


Jack Daniels

Why Your Annual Order Rate Means Nothing

February 21, 2016


When our customers send us a RFQ, we’ve always asked that they share their technical requirements including the BOM, 2D drawings, and 3D flies, inspection standards, Product Requirements Document (PRD), required international certifications and their specification.

We also request the product or program commercial information. How many units will you order over the course of the year, size and frequency of the shipments, the Incoterm (ex works, FOB, CIF, DDP, etc.) and your target price.

This has all been quite typical and an accepted path in the product sourcing & supply chain management business. We may know and have done business with the world’s best linear motion control device manufacturer, but if our customer’s commercial and technical requirements don’t mirror those of the factory, it’s not a good fit for either party.

All logical, with the exception of one very important factor. Many suppliers no longer place any value in the EAU (Estimated Annual Usage) or customer forecast. Instead, the key variable is now your MOU (Minimum Order Quantity).

While forecasts and purchase orders had long been considered the end-all in guiding the negotiation process, many factories, especially those in Asia discount the value, if not totally disregard customer forecasts. They focus solely on the immediate and that takes the form of your PO.

Why is this? Well, it goes without saying that economic times remain uncertain. While forecasts used to assist with the level loading of factories and planning for capacity utilization, nowadays forecasts rarely predict the actual consumption rate. Factories know this and place their trust, and calculate their price on the PO and only the PO.

This trend is magnified by the factories desire to hold “zero inventory”. When I tour suppliers in Asia and elsewhere, I rarely see any appreciable number of components, consumables or raw materials in stock. When we request price breaks based upon an annual forecast, say 10K, 20K and 35K units and releases against those numbers, we get a quotation that shows price breaks based on 1K, 2K and 3K POs and the related MOQs.

What this means is everyone that makes up the supply chain quotes on spot purchase quantities and then get slammed with rush orders. A tough way to do business, but it’s the new reality.

The 2016 version of the old axiom “Money Talks and B.S. Walks”.


Jack Daniels

©2014 Eastbridge