A second source usually gets discussed after something has already gone wrong. A shipment slips, a line goes quiet, and the fastest looking fix is to find another factory that makes something similar. That instinct treats a mount or an arm as a commodity, when what the programme actually sells is a specific drawing, a specific mounting interface, and a joint that still behaves the same way after a year of use. Two suppliers making something similar is not dual sourcing, it is two products sharing a shelf. The work that turns a second supplier into a second source happens on paper, before any production is allocated to it. This article sets out how to judge whether a second source is justified, how to define the product both sources must be able to build, what evidence qualifies the alternate, and how to keep the two in step afterwards.
Dual sourcing is a product control question before it is a supplier question
The phrase “dual sourcing strategy” invites a supplier answer: a list of candidates, a shortlist, a split. In mounting hardware that ordering fails, because the thing being duplicated is not a supplier relationship. It is a controlled product.
A TV mount or a monitor arm is an assembly of stamped and formed steel, machined or cast parts, springs or friction joints, fasteners, and packaging that has to survive a parcel network. Each of those has a specification that can drift without anything looking obviously wrong on arrival. A second source that builds to its own interpretation of a drawing produces an item that fits the same box, carries the same SKU, and behaves differently in the field.
That gives the practical test for the whole exercise. A second source is real when both sources are building the same defined product, against the same released documents, with the same approved bought-in components, and any change to either is recorded once and applied to both. Everything else in this article exists to make that sentence enforceable.
When a second source is warranted for a mount or arm programme
Qualification work has a cost, and it is paid in engineering time, sample builds, measurement, and internal approval cycles rather than in unit price. That cost is worth carrying for some programmes and not for others, so it is worth being explicit about which condition applies.
A repeated SKU, a controlled specification, and a real interruption risk
Three conditions have to hold together before the work pays back.
- The item repeats. The same mount or arm is reordered on a continuing basis rather than bought once for a project. A second source only earns its qualification cost across repeat demand.
- The specification is controlled and owned. There is a released drawing set, a bill of materials, and a named owner who can approve a change. Without that, there is nothing for a second source to be qualified against.
- An interruption would actually hurt. The item anchors a range, carries a retail listing that cannot go dark, or feeds an assembly that stops without it.
Where all three hold, the consequence of doing nothing is that a single interruption is answered under pressure, with samples arriving after the shelf is already empty and approval compressed into whatever time is left. The document that settles whether these conditions hold is your own item master and demand history, read alongside the released drawing set. If no released drawing set exists, that is the first piece of work, not the second source.
When the volume or programme is too small to justify qualification work
The opposite case deserves the same clarity, because unnecessary dual sourcing quietly doubles the surface area of everything that has to be controlled.
A one off project quantity, a promotional item with a defined end date, or a specification still moving between revisions is usually better served by a single controlled source. So is a product whose bought-in content is the real constraint, since qualifying a second assembler while both assemblers draw on the same component supply does not remove the exposure, it relocates it. In those cases the more useful work is often to secure the constrained component or hold buffer stock of the finished item.
There is also a middle route that is frequently the right one. A second source can be qualified and held dormant, with an approved first article on file and no allocated production, so the evidence exists before it is needed. That keeps the qualification current without carrying two live production streams for an item that does not need them.
Define the product that both sources must be able to make
Before any supplier conversation, the programme needs a definition precise enough that two independent manufacturers reading it would build the same item. In mounting hardware this is where most dual-source attempts fail, because the parts that differ are rarely the parts that get specified.
Drawing revision, interface geometry, materials and finishes
The core of the definition is a released drawing package at a named revision, not a set of photographs and a sample. Four areas carry most of the risk.
- Revision identity. Both sources must be building to the same revision, named explicitly, with superseded revisions withdrawn. A second source working from an early sample is the most common way two “identical” items diverge.
- Mounting interface geometry. VESA hole patterns, plate flatness, hole position tolerance and thread specification decide whether the item fits the display it was sold against. These are dimensional and tolerance questions, so they belong on the drawing with tolerances stated, not in a prose specification.
- Material specification. Steel grade and gauge, and any aluminium alloy and temper, determine how a part behaves under load and during forming. A substitution that looks equivalent on a datasheet can change the way a bracket deflects.
- Finish and coating. Coating type, colour reference, coverage on edges and inside formed sections, and the corrosion or adhesion test the finish is accepted against. Appearance and durability are separate acceptance criteria and both need stating.
The evidence that resolves this is a controlled drawing package with a revision index, issued from a single source of truth and reissued to both suppliers together. Where a characteristic matters more than the others, it should be marked on the drawing as critical rather than left for a supplier to infer.
Moving joints, gas springs, fasteners and bought-in components
The moving parts are where two sources diverge in a way the customer feels, because feel is a system property rather than a dimension.
A monitor arm is judged on whether it holds position, moves smoothly, and stays that way. A full-motion TV mount is judged on whether the articulation holds an angle without creep. Both properties come from the interaction of joint geometry, friction surfaces, spring or gas-strut characteristics, and fastener preload. Any one of those changing shifts the result.
- Gas springs and mechanical springs. Force rating, stroke, tolerance band and the adjustment range are functional characteristics of the finished product. Treat the component as an approved part with a named supplier and part number, not as a generic item to be matched on force alone.
- Friction and pivot hardware. Washers, bushings, tension screws and any surface treatment at the joint decide holding behaviour. These are frequently the parts a second source substitutes first, because they look like commodity hardware.
- Fasteners and user hardware. Grade, coating, length and thread class matter structurally, and the installation hardware pack is also what the end user sees first. Both need a defined content list.
- Bought-in and outsourced content. Anything either source buys rather than makes should be identified, because it is the layer where two nominally separate sources can turn out to share one dependency.
The resolving document here is an approved bill of materials that names the specific components a second source may not substitute without approval, alongside the acceptance criteria for the assembled behaviour. Where a characteristic is functional rather than dimensional, define how it will be measured before asking anyone to meet it.
Qualify the alternate source before allocating any production
Qualification is the step that converts a quotation into a source. It is evidence-led, and it happens before any production quantity is committed, because the point of the exercise is to know the answer in advance rather than during an interruption.
Process route and nominated manufacturing site
Two suppliers can quote the same drawing and reach it by different routes. Stamping against laser cutting and forming, welded construction against fastened construction, powder coating in house against coating sent out: each route has different tolerance behaviour, different appearance at edges and radii, and different failure modes.
Ask each candidate to state, in writing and per part, which operations are performed, where each is performed, and which are subcontracted. Two points follow from the answers.
- The nominated site should be named for the item in question. Group capability is not the same as an item being made at a specific place, and the distinction matters for every later approval, since first article evidence applies to the route and site that produced it.
- Subcontracted operations belong in the record. Coating, plating, heat treatment and machining sent outside are part of the process route and change hands independently of the main supplier.
Where the route differs from the incumbent, that is not automatically a problem. It becomes one when the difference is discovered after production, so record it during qualification and decide then whether the drawing tolerances still hold under the alternate route.
First article, critical measurements and packaging approval
The evidence package is what makes the second source auditable later. At minimum it should contain the following, all traceable to the named drawing revision and the nominated route.
- A first article report covering every dimension on the drawing, with actual measured values rather than pass or fail marks, produced from parts made by the intended process.
- Critical characteristic results for the features marked as critical, including mounting interface geometry and any dimension that controls fit to a display or to a mating part.
- Material and finish evidence, meaning mill or supplier certificates for the specified grades, and finish results against the acceptance criteria stated on the drawing.
- Approved component evidence confirming that gas springs, friction hardware and other named parts are the approved items from the approved suppliers.
- Functional evidence for the assembled behaviour, defined by the same method statement used for the incumbent so results are comparable rather than merely present.
- Packaging and print approval, covering carton construction, internal protection, artwork revision, barcodes, country and compliance markings, and the instruction sheet at its own controlled revision.
Packaging deserves its own approval rather than being folded into the product sign-off. It is the part most often left to the supplier, it is what arrives in front of a customer, and a mismatch between two sources on carton dimensions or artwork revision creates warehouse and listing problems that have nothing to do with the mount itself.
One discipline holds the whole package together. Approve first article samples against the drawing and the written acceptance criteria, not against a golden sample from the incumbent, because a golden sample carries the incumbent’s own deviations and quietly makes them the standard.
Keep one controlled change record after qualification
Most dual-source failures happen after qualification, not during it. Two approved sources drift apart because a change reached one of them and not the other, and the divergence only becomes visible when a customer receives two items that behave differently.
Revision control, nonconformance response and re-approval triggers
The remedy is administrative rather than technical, and it rests on a single principle: one change record, applied to both sources, with no supplier-specific side agreements.
- Single point of issue. Drawings, bills of materials, artwork and instruction sheets are issued from one controlled location, at named revisions, to both sources at the same time. Each source acknowledges receipt against the revision number.
- No unrecorded deviation. If a source needs a deviation to run the part, it is requested, decided and recorded against the programme. A verbal allowance granted to one source is the mechanism by which two sources stop being interchangeable.
- Nonconformance handled per source, learning applied to both. Containment stays with the source that produced the issue. The corrective action, and any drawing or criteria change that follows it, is reviewed for both.
- Defined re-approval triggers. Agree in advance what forces new first article evidence. A drawing revision affecting form, fit or function, a change of manufacturing site, a change of process route, a substitution of an approved component, and a long production gap are the usual triggers.
It is worth writing those triggers into the supply agreement rather than leaving them to judgement. A supplier who moves an operation between sites or changes a subcontracted coater has done something entirely reasonable from their side, and only a stated trigger turns it into a notification.
Periodic re-verification serves the same purpose for the dormant case. A qualified but unused second source should be re-verified on an agreed interval, because a first article report from a route that no longer exists is a document rather than evidence.
Comparing candidate second sources on one definition
Buyers in this category are rarely comparing one type of counterpart. Established mount brands such as Sanus, Vogel’s, Chief, Kanto and Echogear publish catalogue products, while manufacturer-side suppliers quote against a customer’s own drawing. Both can appear on the same shortlist, and they answer different questions.
Two distinctions are worth making explicit before comparing anyone.
- Catalogue product against controlled product. A branded catalogue mount is defined by that brand and can change at its own discretion. If the programme depends on a fixed drawing revision and an approved bill of materials, a catalogue item is a substitute product, not a second source, and switching to it is a product change to be managed as one.
- Shared upstream content. Two independent-looking suppliers can converge on the same component vendors, particularly for gas springs and joint hardware. Ask both, during qualification, where the named components come from, since the answer determines whether the second source removes the exposure or duplicates it.
Once those are separated, comparison becomes a like-for-like exercise: same drawing revision, same approved bill of materials, same acceptance criteria, same evidence package. Anything a candidate cannot answer against that definition is a gap in the definition or a gap in the candidate, and it is worth knowing which before allocating work.
Where we sit in a dual-source conversation
We make AV mounting hardware, so we will be plain about what we can and cannot say at this stage. Our published product range includes the TV mount and monitor arm forms this topic concerns, which is a question of product form and nothing more. An actual dual-source programme is a separate matter: it needs the released documents and a written project confirmation from us before anything specific to it can be stated.
ThunderTech is an AV mounting manufacturer, and its published product range covers the forms this topic normally concerns: fixed, tilting, full-motion and ceiling TV mounts, together with mechanical and gas-spring monitor arms. That page is the right starting point for a scope check, meaning whether the product form under discussion sits inside the published range at all. The company overview is useful in the same limited way, as published profile information about the business rather than as a statement about any particular programme.
Everything past that belongs in a written programme confirmation. Specifically:
- Whether a given item, at a given drawing revision, can be quoted and made, and by which process route.
- Which manufacturing site is nominated for that item, and which operations are subcontracted.
- Which approved components would be used, and whether any substitution is being proposed.
- What first article, measurement, functional and packaging evidence would be supplied, and in what format.
- How change notification, deviation requests and re-approval triggers would be handled.
- Which market documentation and markings the destination market requires for the finished item.
None of those are established by a website, and a supplier who answers them in writing is easier to qualify than one who answers them well in conversation. Send the drawing package and the acceptance criteria with the enquiry rather than a category name, and the reply can be assessed as evidence instead of as a claim.
A working sequence for setting up a second source
Run these in order. Each step produces the input the next one needs, and skipping one usually shows up as rework later.
- Confirm the item repeats, the specification is owned, and an interruption would genuinely hurt.
- Release a controlled drawing package at a named revision, with tolerances and critical characteristics marked.
- Publish the approved bill of materials, naming the components that may not be substituted.
- Write the acceptance criteria, including how functional behaviour will be measured.
- Ask candidates for the process route, nominated site and subcontracted operations, per part and in writing.
- Require a full first article package from the intended route, plus material, finish, component and functional evidence.
- Approve packaging, artwork and instruction sheets as separate controlled items.
- Agree change notification, deviation handling and re-approval triggers in the supply agreement.
- Set a re-verification interval, including for a qualified source that is being held dormant.
Questions TV-mount and monitor-arm buyers still ask about dual sourcing
What is the best strategy for dual sourcing TV mounts and monitor arms?
Define the product before selecting the supplier: a released drawing revision, an approved bill of materials, and written acceptance criteria that both sources build against. Qualify the alternate with a full first article package from its intended process route before allocating any production. Then maintain one change record so a revision reaching one source always reaches the other.
Should a second source build the same drawing revision or its own equivalent design?
For a dual-source programme it should build the same released revision, because an equivalent design is a different product that happens to look similar. Equivalent designs are a reasonable answer to a different question, such as replacing a discontinued item, and they should be managed as a product change with their own approval. Mixing the two under one SKU is what produces field differences that nobody can trace afterwards.
What evidence should be required before a second source builds sellable stock?
A first article report with actual measured values from parts made by the intended process, results for the characteristics marked critical, and material and finish certificates against the specified grades. Add confirmation that named components such as gas springs and joint hardware are the approved parts, plus functional results measured by the same method used for the incumbent. Packaging, artwork and the instruction sheet should be approved as separate controlled items.
Do gas-spring arms need different treatment from fixed TV mounts?
The framework is the same, but the risk concentrates in different places. A fixed mount is mostly dimensional, so drawing tolerances and finish carry the qualification. A gas-spring or mechanical arm adds functional behaviour that comes from spring characteristics, joint hardware and fastener preload, so those components need naming in the approved bill of materials and their assembled behaviour needs a defined measurement method.
How should packaging and instruction sheets be handled across two sources?
Treat them as controlled documents with their own revisions, issued from the same single source as the drawings. Approve carton construction, internal protection, artwork, barcodes and markings from each source separately, since these are frequently where two approved sources visibly diverge. Reissue any artwork change to both sources at the same time and record the acknowledgement against the revision number.
Can a second source be qualified and then left unused?
Yes, and for many programmes that is the proportionate answer, since it puts the evidence on file without running two live production streams. The condition is that the qualification stays current, which means agreeing a re-verification interval and applying every drawing, component and artwork change to the dormant source as well. A first article report from a route that has since changed is a document rather than usable evidence.