I was reading an article recently about Apple MacBook Pro keyboard issues, affecting the current generation of products, on which this article is being written. I also have an iPhone sitting next to me playing “music” whilst I wait for a call-center agent to reply on a travel issue. In both cases, I am dependent on their correct functioning. My past experience across many products is that my overall experience is also dependent on how product support is delivered in case of hardware failure.
Design and business choices strongly affect in-life support capability. They affect not only the basic ability to repair a product but also, through the cost and availability of spare parts, the economic policies for repair.
How do we influence and make these choices?
These choices can appear to be “no-brainers” once they are highlighted.
Standard components
Consider the wheel studs on your car? I was recently driving on a 4-lane highway at high speed, when 3 of the 5 studs on a rear wheel sheared. Fortunately, we were able to bring the car to a stop safely, but clearly it could not be driven further. Contact with the national automobile association led to contact with the local garage, who sent a truck to retrieve us. In the meantime, with the information I had given, the local garage ordered replacement studs and nuts, ready for our arrival. The point here is that the studs were a standard size and could be obtained within 30 minutes of our “event.” We were safely back on our journey within 75 minutes!
The point is that the design choice by the car manufacturer was to use a standard component, rather than a special-to-type. Consider the alternative: what benefit would there be to make a special-to-type stud? I can’t think of one.
Feasibility of repair as a trade-off
But to return to computing and phone products. I spent several years with RIM (now BlackBerry) during their good years. Achieving mechanical robustness and long life was always a challenge – one option available to improve reliability and product life (not a first choice) was to apply an epoxy underneath the major electronic components. A non-reworkable epoxy often performed better than a reworkable one but would be the last choice because of its impact on ability to replace defective components. Ability to repair was a key ingredient of these high-end electronics.
But this is not always the case. In the past I have tried to repair an LCD TV and failed. The relevant circuit boards were not available. The manufacturer had chosen not to keep any spares, or at least not make them available. I would take it that this was a logistical and economic decision. And this is where we started.
Efficient Logistics
Technical feasibility clearly affects ability to repair and is a design decision. The logistical difficulties to store and distribute parts probably comes next. Complexity of any repair will affect training requirements and equipment needed and therefore affects who could do the repair.
Cellphones are some of today’s most compact and most complex consumer product. Adhesives are now used extensively as an alternative to screws and brackets in securing parts. However, the choice of adhesive affects repair – so we should balance the life and strength of the adhesive with ability to repair.
I have not had cause to repair my 2017 MacBook Pro, but I have read that there is more use of adhesive internally than on my previous 2012 MacBook Air. Replacing the MacBook Air battery was quite straightforward, as was upgrading its SSD storage. Upgrading SSD on this MacBook Pro is not possible, and the battery is glued in place rather than screwed. Others have scored the MacBook Pro as 1 out of 10 for reparability, with 10 being easiest. I wonder what the benefits of this approach are?
Training requirements
Apple has a well-oiled repair system. I recently had to request repair of my iPhone under warranty. …2-days shipping a replacement to me, with return of the defective unit in the same packaging whilst the nice guy from FedEx waited (and helped me), is difficult to beat. This approach, of mainly undertaking repairs centrally, avoids needing distribution of parts to local repair centres. Any special tools and training needed to tear down and replace parts do not need to be available in a large number of locations. So, extrapolating this to the MacBook Pro, maybe the increased use of adhesives does not have a major downside. And maybe, adhesives offer at least equal reliability. Choice of adhesive still needs to be right – sticking but not too much sticking.
Interchangeable parts
I have also replaced parts in my daughter’s garage door mechanism over the past years. I can do so only because, despite the profusion of garage door automatic opener systems, the basic components are interchangeable and can be sourced.
But why does the garage door opener continue to offer parts such that you could continue to replace parts, even until you are left with nothing more than the shadow on the ceiling of the original unit? Like the proverbial axe that has had 5 heads and 4 handles? …nothing left of the original ax but the memory. My experience so far is that the nylon moulded parts are the ones that have failed. To keep parts available means that either a life-times worth of parts must be stored, or that the production moulding tools need to be still available to top-up the parts stock, or that current parts remain interchangeable with older units.
Long-term business strategy
My understanding that the garage door opener parts are indeed interchangeable with current models, going all the way back 25 years. Clearly there is no desire to introduce major changes on a system that works – this is a business as well as a design decision. Does this indicate that the manufacturer has, by now, a good set of data to indicate optimal lifetime and reliability of the garage door opener and knows that it has pretty well got the design right? Does the repairable design facilitate incremental reliability improvements (by, say, improvement of the nylon material and its moulding) without affecting form, fit or function?
Brand image
Maybe manufacturers don’t make much profit on replacement parts, but to keep a good brand image making current-manufacture parts available doesn’t seem too difficult. Internet ordering makes it even easier.
Of course, not everyone will wish to tackle a garage-door opener repair but, with basic tools of standard screwdrivers and wrenches, it is certainly feasible for the technically inclined. YouTube even covers the aspect of “training.”
I believe that ease of repair has been a factor in the design and construction of the opener, concurrent with a business decision to retain basic interchangeability over the past 25 years. My belief is that this has not compromised reliability within the home-use environment. Indeed, it has also perhaps facilitated incremental improvements that have not compromised form, fit or function. And helped deliver a good brand image.
All the factors discussed potentially have an impact on the benefits to be gained from reliability, even if they don’t directly affect the actual reliability or product life. If you are a reliability engineer, I believe you should be part of the discussion to optimize reliability benefits from product support.
If you wish to discuss this further, maybe to cover your project, please contact me.
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