What drives the price of a custom part

Every custom fabrication quote comes down to four levers: material, machine time, setup, and finishing. Understanding how each one works — and how they interact — lets you make small design decisions that compound into meaningful savings without giving up what the part actually needs to do.

Key takeaways

• Material cost includes the stock you cut from, not just what ends up in the finished part — nesting reduces waste for everyone
• Machine time is usually the largest lever; cut-line length and print height are the two numbers that move it most
• Setup is a fixed cost per job, so quantity is the fastest way to drop per-part price
• Finishing is the most underspecified lever — "as clean as it comes off the machine" and "showroom-ready" are very different quotes
• Sending editable files (SVG, STEP, STL) lets us nest, orient, and optimize before cutting or printing

How does material cost actually work in fabrication?

You pay for the material the part is made from, plus the waste inherent in the process. In laser cutting, that means sheet stock — acrylic, plywood, MDF, mild steel. A 600 × 400 mm sheet of 3 mm clear acrylic has a fixed cost whether your parts use 40% of it or 90%. That's why nesting matters: when we arrange multiple parts from your order (or combine your parts with another job's stock) onto a single sheet, everyone pays less per part.

Material choice compounds with sheet thickness. Switching from 6 mm to 4 mm acrylic on a bracket that doesn't need the extra rigidity cuts material cost and (because thinner cuts faster) machine time simultaneously. We'll flag it in the quote if there's an obvious substitution that doesn't compromise function.

In 3D printing, material cost is simpler — you pay for the volume of resin or filament in the part plus support structures. Hollowing a thick-walled model with a solid interior reduces material cost proportionally; most structural FDM parts need 20–40% infill, not 100%.

Why is machine time usually the biggest lever?

Machine time is the cost that scales fastest with design complexity. A laser cutting a simple 150 mm circle takes under ten seconds. The same laser cutting a detailed snowflake outline at the same size might take three minutes. An engraved logo inside the circle could add another five.

Cut-line length is the primary driver in laser cutting. Every millimetre of vector path costs machine time, which is why we encourage simplifying outlines, reducing internal engrave areas, and avoiding decorative perforations that look good on screen but run slowly on the machine.

In 3D printing, the equivalent is part height and total volume. FDM prints at a fixed speed per layer — a 150 mm tall part takes roughly three times as long as a 50 mm tall part of the same footprint. Reorienting a print to reduce height (sometimes at the cost of a wider footprint) is one of the most effective ways to cut machine time. SLA is different: it cures an entire layer simultaneously regardless of how full that layer is, so SLA cost scales with layer count (height) and total volume, but less with the complexity of each layer's outline.

What is setup cost and when does it disappear?

Setup covers everything that happens before the machine starts cutting or printing: loading and checking the file, fixturing or levelling the stock, running test cuts on scrap, and dialling in parameters for an unusual material. For a laser job on standard 3 mm acrylic with a clean SVG, setup is fast — maybe ten minutes. For an unusual material we haven't run before, setup could be 45 minutes of parameter testing.

The critical thing about setup: it's the same whether you order one part or fifty. That fixed cost gets divided across all units, which is why quantity dramatically drops per-part cost. A job with a $40 setup spread across 40 parts adds $1 per part; spread across 2 parts it adds $20 each.

Design changes that come in after setup — a revised file, a different size — reset the clock. Getting the design right before we start is worth more than the fastest turnaround after you've placed the order.

How much does finishing add, and what should you specify?

Finishing is the most variable and most underspecified lever in custom fabrication. "Finished" means something different to everyone, so we try to ask before we quote rather than assume.

In laser cutting acrylic, cut edges come off with a slightly frosted appearance. Flame polishing restores optical clarity to edges — it looks beautiful, but it adds labor proportional to total edge length. For parts that are painted, bonded, or installed out of sight, frosted edges are invisible and flame polishing is pure waste. For a display piece or retail product, it's worth every penny.

Deburring metal cut parts is often non-negotiable for safety but varies in intensity. A quick pass to knock sharp corners off sheet steel takes minutes; smooth blended edges ready for anodizing take longer. Tell us how the part will be handled and finished downstream, and we'll spec the right level.

3D printed parts have their own finishing spectrum. FDM parts straight off the bed have visible layer lines (typically 0.2 mm at standard settings). A light sand and spray primer makes them look injection-moulded; full paint and clear coat turns them into finished products. SLA parts have much finer layer lines and are often usable straight from the cure station, but support witness marks need sanding if they're on a visible surface. Be specific about what the part will look like in its final application.

What design choices reduce cost the most?

After seeing hundreds of jobs, the highest-leverage design changes fall into a consistent list:

Simplify geometry. Every curve segment, every internal cutout, every decorative feature adds cut time. If a slot can be rectangular instead of rounded, it cuts faster. If a logo can be a sticker instead of an engrave, the laser job is cheaper.

Reduce part height in 3D printing. Orienting a bracket to print on its wide face instead of standing upright can cut print time in half. We'll suggest reorientations when we see them.

Order in batches. Even a batch of three or four spreads setup cost enough to make a visible difference. If you know you'll need more of a part later, ordering together is almost always cheaper than ordering twice.

Send editable files. An SVG lets us check and optimize cut paths before machining. A STEP file lets us nest 3D prints on a build plate efficiently. A PDF or rasterized image forces us to redraw, which takes time and introduces risk of error.

Specify the finish you need, not the finish you can imagine. "Clean enough to glue" and "showroom" are genuinely different line items. We'd rather ask once and get it right than re-quote after you've seen the first batch.

Curious where the money is going on your specific part? Start an order, describe the function and finish, and we'll break down the quote so you can see exactly which lever is driving the cost.