When you’re sourcing metal parts, the question isn’t just “who can make this?”–it’s “what’s the best way to make this?”
The answer depends on many factors that experienced metal parts manufacturers evaluate instinctively, but that can leave less experienced companies scratching their heads.
After decades in metal parts manufacturing, Jones Metal has developed a systematic framework for evaluating parts and matching them to the right metal forming process.
This guide walks you through how we think about part manufacturing to help you determine the best way to make your part.
5 Metal Parts Production Factors That Matter Most
Choosing the right manufacturing approach isn’t about finding someone who can make your part. It’s about matching process, capability, and cost to your specific requirements. Here’s how experienced manufacturers evaluate part inquiries.
1. Material Type: Your First Filter
Before we discuss anything else, we need to know what material your part requires. This single factor tells us roughly 80% of what we need to know about whether a part is a good fit for our capabilities.
Materials like titanium, Inconel, specialized aluminum alloys, and stainless steels typically indicate aerospace, defense, or medical applications–markets that require sophisticated quality systems and manufacturing expertise.
When we hear galvanized steel, cold-rolled steel, or automotive-grade materials with numeric designations, we know we’re likely looking at high-volume, cost-sensitive applications.
The material tells us not just what we’re working with, but what market segment you’re in–and therefore what your real needs and expectations are likely to be.
2. Volume Requirements: Low, High, or Somewhere In Between
Volume dramatically affects which metal forming processes make economic sense.
Many specialized manufacturers focus on customers who order around 1,000 parts annually in batches of 250-500. This volume range allows for cost-effective tooling while maintaining the flexibility that aerospace and defense applications typically require.
When volumes reach 30,000+ parts per year, the manufacturing approach changes entirely. Shops equipped for high-volume work are set up completely differently from those specializing in low-volume work.
Neither approach is better–they’re simply optimized for different needs.
3. Tolerance Requirements and Their Impact
Not all tolerances are created equal, and some are difficult to achieve consistently.
Basic dimensional tolerances are straightforward. But when you get into geometric dimensioning and tolerancing (GD&T)–profile callouts, datum structures, and flatness requirements–the difficulty level increases exponentially.
The real challenge with tight tolerances is material variation. A sheet of material marked as 0.036″ thick might measure 0.036″ in one spot, thin to 0.034″ a few inches over, then back to 0.036″. When you’re holding three thousandths of an inch tolerance (roughly the thickness of a hair) across a 40-inch part that moves when released from fixturing, this natural material variation becomes a significant problem. Special materials with guaranteed thickness uniformity exist, but a single sheet might cost $5,000 to $10,000.
High-volume manufacturers solve this with million-dollar tooling and automated inspection systems that detect trends before parts go out of tolerance. Low-volume specialists work differently, focusing on process control and material selection to achieve tight tolerances without the automation infrastructure.
4. When Surface Finish Drives the Process
Surface requirements can make or break a part’s manufacturability, especially for customer-facing applications.
Soft materials like aluminum, copper, brass, and bronze can easily scratch. Any metal-on-metal contact creates visible marks. Even material from the supplier may only be guaranteed good on one side.
When surface condition is critical, manufacturers must:
- Buff material before forming
- Apply protective plastic coating during the forming process
- Build custom fixtures to prevent metal-on-metal contact during handling
- Cover all work surfaces
- Create custom packaging for each part
- Transport parts in protective containers through the entire factory
One scratch can reject an otherwise perfect part. It’s work that requires exceptional process control.
5. Part Geometry: Why Simple Can Be Complicated
Here’s something about the metal forming process that surprises most people: the simpler a part looks, the more challenging it can be to manufacture consistently.
A part with just a slight bend can be surprisingly difficult. But why?
Because when you trim a slightly-bent part, it wants to spring back and flatten. Parts with sharp bends hold their shape better through the trimming process. Simple geometry offers fewer mechanical advantages to maintain form.
Simple parts are also more susceptible to material variation. Different material batches react differently to forming, and subtle differences become obvious on simple parts. Complex geometry often hides these variations.
Don’t assume a simple-looking part will be simple to manufacture. Often, the opposite is true.
Matching Parts to the Right Metal Forming Processes
Once you’ve evaluated material, volume, tolerances, and surface requirements, you can start thinking about which metal forming process makes sense.
Process #1: Fabrication (For Sharp Corners and Low Volumes)
Best For:
- Parts with sharp corners (think metal boxes or enclosures)
- Low to medium volumes (hundreds, not thousands)
- Applications where bend-and-weld construction is acceptable
The Advantages: Fabrication is often the only viable option for parts with sharp corners. Forming processes struggle with sharp angles because they tend to rip through material, making bend-and-weld construction the practical solution.
The Challenge: Fabrication costs don’t scale down with volume the way other processes do. A fabricated metal box made in quantities of 200 parts is probably as inexpensive as it’s going to get. Whether you’re making 500 or 10,000 parts, the price stays relatively flat because the process can only go so fast.
Process #2: Spinning (For Round Parts)
Best For:
- Round, symmetrical parts (think funnels, cones, bowls)
- Low to medium volumes
- Parts requiring rolled edges
- Budget-conscious projects
The Advantages: Spinning can create complex round shapes from flat blanks in a single operation, including rolled edges that would require additional operations in other processes. Tooling can be made from wood, keeping costs low. A spinner might sell you a part for $15 that would cost significantly more through other metal forming processes.
The Challenge: If your part isn’t round, spinning isn’t an option. And while spinners can handle radiused forms beautifully by rolling material over the tool, squared or flat edges are difficult.
Process #3: Hydroforming (For Complex Shapes in Moderate Volumes)
Best For:
- Parts of multiple shapes with complex geometry
- Volumes of 1-500 parts per run
- Applications requiring good radius control (double the material thickness is ideal)
- Parts up to 32 inches in diameter (see more on fluid cell forming below)
The Advantages: Hydroforming tooling costs about half what stamping dies cost, making it economical for lower volumes. With hydroforming, metal parts manufacturers can handle complex shapes that would otherwise be difficult to fabricate, with the flexibility to form various materials and thicknesses.
The Challenge: Hydroforming struggles with shapes that narrow dramatically at the top–the punch can shove material into open areas and potentially rip through. An example would be a funnel. The hydroforming process is best for parts with consistent geometry or shapes that flare outward.
Process #4: Fluid Cell Forming (For Larger, Gentler Shapes)
Best For:
- Large parts (blanks up to 6 feet long, 27 inches wide)
- Shapes with generous radii (quarter-inch radius works great)
- Parts requiring up to 5.5 inches of depth
The Advantages: Fluid cell forming accommodates much larger starting blanks than traditional hydroforming, making it ideal for bigger components. It excels at creating flowing, organic shapes with generous radii across large surface areas.
The Challenge: Fluid cell forming doesn’t achieve radii as sharp as hydroforming can. If your design requires tight, crisp corners or aggressive angles, this process will struggle. It’s optimized for fluid geometry, not sharp transitions.
Process #5: Stamping (For High-Volume Parts)
Best For:
- High volumes (10,000+ parts per run)
- Applications requiring extremely tight tolerances
- Parts where high tooling costs are offset by large production runs
The Advantages: Stamping dies can cost $100,000 or more, but they deliver the lowest piece prices at volume. If you’re buying 50,000 parts, you’ll recover that tooling investment on the first run. Stamping can also “crush” material and use ironing operations to achieve extremely tight tolerances.
The Challenge: If you’re ordering a few hundred parts, stamping’s high tooling costs make it economically unfeasible. But for true high-volume metal parts production, it’s often the only way to achieve the combination of speed, consistency, and cost-effectiveness required.
When Multiple Processes Come Together
One of the most sophisticated scenarios in metal parts manufacturing involves aluminum parts that require forming, heat treating to a hardened condition (like T6), and precision machining to tight tolerances. This combination requires deep expertise in all three areas, which can be challenging because:
- You can’t form aluminum in its hardened state–it must be formed soft, then hardened
- Heat treating changes the material properties in ways that affect final dimensions
- Machining operations must account for the hardened state
- Coordinating all three processes to deliver a part within tolerance requires extensive experience
This is where specialized metal parts manufacturers separate themselves from general fabricators. It sounds simple–form it, harden it, machine it–but executing all three in sequence while maintaining tolerance requires sophisticated process control.
Perfecting this process takes years of refinement and process knowledge that can’t be easily replicated.
Questions to Ask Before Requesting Quotes
Here are the key questions to answer before approaching a metal parts manufacturer:
- What material does your part require? Be specific–not just “aluminum” but the exact alloy.
- What quantities do you need, and how will you order them? Total annual volume matters less than typical order quantities.
- What are your tolerance requirements? Are they standard dimensional tolerances or geometric tolerances (GD&T)?
- What surface finish is required? Is this a hidden component or customer-facing? What’s your RA value requirement?
- Is your part round or non-round? This immediately narrows the field of applicable processes.
- What’s the size of your part? Starting blank dimensions and depth of draw affect process selection.
- What radius requirements exist? Sharp corners and tight radii significantly limit manufacturing options.
- Does your part require secondary operations? Heat treating, machining, coating, plating?
- What’s your timeline? First-article timeline versus production run timing.
- What’s your budget reality? Are you looking for the lowest possible price, or the right manufacturing partner for a critical application?
Finding the Right Metal Parts Manufacturer
The goal isn’t just finding someone who can make your part–it’s finding a company whose expertise matches your needs.
- Market alignment: Are you in aerospace, defense, medical, or automotive/consumer products?
- Volume match: Does your order quantity fit their operational model?
- Capability fit: Do they excel at your part’s specific requirements?
- Quality system match: Do their processes align with your inspection and documentation needs?
- Communication: Can they explain why they’re recommending a particular approach?
When these factors align, you get more than just a supplier–you get a manufacturing partner who understands your application and can guide you toward the best solutions.
Why Experience Matters in Metal Parts Manufacturing
Manufacturing decisions are complex because they involve tradeoffs. A process perfect for one application might be completely wrong for another. Material, volume, tolerance, surface finish, geometry–these factors interact in ways that aren’t always obvious.
This is why experienced metal parts manufacturers don’t just quote parts–they consult on them. We might tell you that your part would be better as a spinning project, or that your tolerance stack-up will be difficult to achieve consistently, or that your volume would be better served by a different process entirely.
That’s not us turning down work–that’s us ensuring you end up with a manufacturing solution that actually works.
Need Help Evaluating Your Part?
The best metal parts manufacturer for your project isn’t necessarily the one with the lowest quote–it’s the one whose capabilities align with what your part actually needs. At Jones Metal, we specialize in complex, low-to-medium volume metal forming for aerospace, defense, and medical applications. Contact us to discuss your part requirements. We’ll give you an honest assessment of whether we’re the right fit–and if we’re not, we’ll point you in the right direction.