What Are Product Design Engineering Services?
Product design engineering services cover everything from the first geometry decision to the production-ready CAD file — including material selection, design for manufacturability (DFM) review, 3D modelling, 2D engineering drawings, and prototype validation.
Most design services end with a file. Ours ends with a manufactured part. At Plast Fab Works, our plastic product designers are the same team that operates the injection moulding machines, CNC machining centres, and fabrication equipment. Every wall thickness call, every draft angle decision, every gate location choice — made by someone who will personally run the tool that makes your part.
The result is plastic product design and development that doesn't need revision when it reaches the factory floor — because it was designed on the factory floor. No handoff, no translation errors, no first-article surprises.
Design Services for Every Process We Run
Plastic Part Design for Injection Moulding
Key Design Parameters We Specify on Every Moulded Part
Nominal wall thickness:
1.5 mm (min) to 4 mm (max) for most engineering thermoplastics
Draft angle:
1° minimum per side on all vertical faces; 2° on textured surfaces
Rib design:
rib thickness = 50–60% of wall thickness to prevent sink marks on visible face
Boss geometry:
boss OD = 2× insert OD, with gussets to adjacent walls
Gate location:
placed at thickest section, away from structural and cosmetic faces
Shrinkage compensation:
specified per grade (PP = 1.5–2.5%; Nylon PA6 = 0.7–1.5%)
From Brief to Production-Ready CAD
1. Brief & Requirements Capture
We start with what the part must do: loads, fluids, mating interfaces, surface finish requirements, operating environment. This is where most design studios get vague. We go specific — because our DFM decisions depend on it.
2. Concept Geometry & DFM-Parallel CAD
3D modelling with DFM applied as the model is built — wall thickness, draft angles, tool access, and parting line strategy resolved in real time, not in a separate review after the geometry is done.
3. Process Selection & Material Recommendation
Before a single sketch line is drawn, we confirm the right manufacturing process and material grade. CNC for low volumes, injection moulding for scale, fabrication for large structural components. Our material knowledge spans Nylon, Delrin, ABS, HDPE, acrylic, PC, and PEEK.
4. DFM Report & Client Approval
We deliver a DFM report alongside the CAD model: wall thickness heatmap, draft angle analysis, flagged features with recommended changes, and estimated cost impact for each design decision. You see the manufacturing implication before you approve anything.
5. Production Handoff or Direct Manufacturing
If you're manufacturing with us, the design goes straight to our floor — no file conversion delays, no re-quoting. If you need files for your own supplier, we deliver STEP, IGES, DXF, and full 2D engineering drawings with GD&T.
Why Choose Plast Fab Works as Your Plastic Product Design Company?
Designer = Manufacturer
Our designers share floor space with the operators who run the machines. Every DFM decision is made by someone who has personally produced the part. No file handoff. No translation errors. No first-article surprises.
DFM Report on Every Project
We review your design for manufacturability before quoting and deliver a full DFM report with every engagement — wall thickness heatmap, draft analysis, flagged features, and cost impact estimates per decision.
All Three Processes, One Team
Injection moulding design, CNC plastic part design, and custom fabrication design — all under one roof. We recommend the right process for your volume and tolerances, then design and manufacture it.
Explore our custom plastic fabrication services
Need a mould? See our mold design services
Industries We Design Plastic Parts For
🏭 Industrial & Manufacturing
Machine guards, jigs, fixtures, conveyor components, process housings
🚗 Automotive
Interior trim, sensor housings, under-bonnet components, prototype parts
Instrument trays, device housings, specimen holders, clean-room components
⚕️ Medical & Laboratory
📱 Electronics & Technology
Device enclosures, connector blocks, PCB mounts, DIN rail components
Cladding components, structural profiles, covers, bespoke fabricated assemblies
🏗️ Construction & Architecture
🛒 Retail & Consumer Products
Appliance parts, display fixtures, POS components, packaging insert trays
Frequently Asked Questions
1. What is design for manufacturing (DFM) and why does it matter?
Design for manufacturability (DFM) is the practice of designing parts so they can be produced efficiently, consistently, and to specification without costly rework. For plastic parts it covers wall thickness, draft angles, gate location for moulded parts, tool access for CNC parts, and material-specific geometry rules. Without DFM, a design that looks perfect in CAD will fail at first article — through warping, sink marks, tool marks, or tolerance stack-ups that prevent assembly. Our product design engineering services apply DFM throughout the design session, not as a final gate.
2. Do I need to know which manufacturing process I want before contacting you?
No. Process selection is part of what we do in the first session. We'll ask about your production volume, required tolerances, material, and timeline — and recommend the right process. As a general rule: CNC machining for under 500 parts, injection moulding for over 1,000 per year, and custom fabrication for large, thick-walled, or one-off structural components.
3. How do you design a plastic product from scratch?
We start with the application requirements: what the part does, what forces it carries, what fluid it contacts, and what surface finish is required at mating faces. From there we select the process and material, build 3D geometry with DFM applied in parallel, and deliver production-ready CAD with a full DFM report. For complex parts, we recommend a CNC-machined prototype before any mould tooling investment.
4. What file formats do you deliver?
STEP and IGES for 3D geometry (universal, process-independent). SolidWorks native (.SLDPRT) on request. DXF and DWG for 2D profiles. PDF engineering drawings with GD&T, tolerance callouts, and material specification. If you're manufacturing with us, files go directly into our production workflow — no conversion step needed.
5. Can you redesign an existing part for a different manufacturing process?
Yes, and this is a common request. Parts originally designed for CNC machining often need significant geometry changes before they're suitable for injection moulding — wall section uniformity, draft angles, parting line strategy, and gate location are all different. Send us your existing STEP file and the target process and we'll assess what needs to change.
