DFMA: SHOULD COSTING
DFMA: PRODUCT SIMPLIFICATION
Most design reviews approve geometry. They do not challenge the manufacturing consequences of the decisions inside that geometry. The fix is simple: bring manufacturing in early and give the team a shared, quantifiable way to compare options before the design hardens.
The Most Expensive Sentence in Product Development
It is not "We missed the schedule."
It is: "We'll let manufacturing figure it out."
Because the moment that sentence is spoken, you are accepting a future where cost, complexity, and risk get discovered late, when changing anything is slow and political.
And the reason it happens is usually not incompetence. It is structural. The most important person missing from many design reviews is someone from manufacturing. Not as a final-stage "DFM check," but early enough to challenge assumptions while the design can still change easily.
The Design Review Everyone Recognizes
A typical design review has familiar roles. Engineering presents the design. The program manager checks dates. Leadership checks progress. A few tolerances get discussed. The slide deck gets approved.
Then the design goes to manufacturing and the "real review" begins. That is where you find out the housing cannot be molded as drawn, a fastener is inaccessible without a special tool, the assembly sequence requires three hands, tolerance stack-up guarantees rework, and the part count drives a BOM that creates sourcing and quality headaches for months.
None of those are manufacturing surprises. They are predictable consequences of design decisions. The problem is that many design reviews do not include the person who can spot those consequences early, or they include them too late to matter.
How Cost Gets Baked in Quietly
Imagine a small enclosure assembly. Engineering designs it one way. Manufacturing sees it and immediately identifies hidden cost. Now imagine the same assembly after an early manufacturing-led review.
Original Design
After Early DFMA Review
A Late Manufacturability Review Is Not the Same as a Better Design
Many companies will say: "We do include manufacturing." Often what they mean is: "Manufacturing reviews the final design and flags anything impossible." That is better than nothing. But it has a ceiling.
Late Reviews Can Only Find Problems, Not Prevent Them
When manufacturing sees a near-final design, the architecture is already set. The fixes available are small: add a chamfer, widen a tolerance, change a fastener. The biggest opportunities were upstream: part count, process selection, function integration, assembly sequence choices.
"Manufacturable" Can Still Be Expensive and Overbuilt
A design can be fully manufacturable and still be the wrong design. "Can we build this?" is not the same as "Should we build it this way?" Cost reduction comes from the second question.
The Dynamic Changes When Manufacturing Is Early
When manufacturing participates at concept stage, the conversation shifts from feasibility to optimization, from opinions to trade-offs, from handoff conflict to iteration. That shift is where major cost and complexity improvements actually happen.
"Can we build this?" accepts the design. "Should we build it this way?" improves it.
The Questions That Change Designs
These are the questions that turn a design review from a formality into a cost reduction tool.
Minimum part criteria: For every part, ask:
Does it move relative to adjacent parts?
Does it need a different material?
Does it need to be separate for assembly or service?
If the answer is "no" across the board, that part is a candidate for elimination or integration.
Process and cost questions:
Why this process? What is the next best alternative?
What operations does this choice force?
Fixtures, secondary ops, finishing, inspection
What does this do to assembly time and error risk?
What does it do to sourcing, qualification, and inventory complexity?
These are not abstract questions. They have real dollar outcomes. The earlier you ask them, the cheaper it is to act.
Want to Test This on One Assembly?
Pick one assembly that is high-volume, high-cost, or a repeat pain point. Run a DFMA review in parallel with your normal design review and compare what each approach catches.
Schedule a DFMA Walkthrough →Why the Best Teams Use a Shared Language, Not Louder Opinions
Even when manufacturing is present, teams often lack a shared way to compare options. Design engineers speak in geometry and tolerances. Manufacturing speaks in cycle time and process capability. Without a common framework, you get opinion battles: "We should machine it." "We should cast it." "We don't have time." And the default outcome is predictable: keep the design and move on. DFMA changes that by quantifying the trade-offs so the conversation becomes productive instead of political.
DFMA does not make one side win. It gives both sides the same numbers. That is how you move from opinion battles to better designs.
What Changes When You Get This Right
When manufacturing has an early seat and the team shares a way to evaluate trade-offs:
How to Fix Your Design Review Starting Next Week
Invite Manufacturing to Concept Reviews, Not Just Final Reviews
Concept stage shapes architecture. Final stage shapes chamfers.
Require Every Part to Justify Its Existence
Use minimum part criteria as a standard review step. It forces simplification.
Require a Process Choice and a Second Option
Do not accept "default machining" or "we always do it this way" without comparison.
Start With One Product
You do not need a process overhaul. You need one pilot that proves the gap.
The Best Design Review Is a Conversation
Every product carries the DNA of its design reviews. If you want that DNA to produce simpler, cheaper, more buildable products, the fix is not a better slide deck. It is a better conversation, earlier, with the right people in the room.
Make sure manufacturing is in the room early. Not to bless the design. To improve it.
See What a DFMA-Led Design Review Looks Like
We will walk you through a real assembly and show you how teams use DFMA to quantify trade-offs early and drive better decisions.
Schedule a Walkthrough →
