Injection Molding: Working with Welch Plastics
Injection molding reigns supreme in the world of plastic manufacturing. From delicate medical devices to ubiquitous consumer products and automotive components, this process has emerged as the standard for scalable, high-volume production with the most accurate precision and consistency.
While the process is key, your success depends on something even more important—whether you choose the right plastic manufacturer.
If you're in the market for custom plastic fabrication or exploring injection molding in Las Vegas, this guide will be your introduction to the process, its benefits, and how to find the right partner—Welch Plastics, for example—to produce your product.
What is Injection Molding?
Injection molding is a plastic manufacturing process that involves injecting molten plastic into a mold cavity in a predesigned mold, under pressure. The plastic is then cooled, and it hardens into the shape of the mold cavity. The process continues to repeat itself, making injection molding ideal for producing high-precision parts in mass production.
Injection molding most typically uses thermoplastics, such as ABS, polycarbonate, polypropylene, and polyethylene, although advanced elastomers and specialty materials exist.
Why Choose Injection Molding?
When you need custom plastic fabrication that is scalable, consistent, or cost-effective, injection molding has benefits that include:
✅ High Precision
Allows for tight tolerances and complex geometries.
✅ Cost Effectiveness
The cost per part drops considerably during high-volume runs, after paying the upfront costs of tooling.
✅ Scalability
Ideal for virtually unlimited runs of units (1,000+).
✅ Material Versatility
Compatible with a variety of polymers, including recyclable and bio-based.
✅ Good Design Flexibility
Injection molding provides great design flexibility, from snap-fit parts to overmolded parts.v
How Injection Molding Works: Step-by-Step
Knowing the process of how injection molding works lets you better collaborate with your plastics manufacturer, no matter if you’re a startup company or a brand. Here's how the process works:
Material Preparation
Raw material, usually plastic pellets, is fed into a heated barrel where it melts.
Injection
The molten material is injected under high pressure into a mold cavity.
Cooling
The material cools and solidifies inside the mold, taking its shape.
Ejection
The finished part is ejected from the mold.
Repeat
The process is repeated for mass production.
The process then repeats itself, allowing for the mass production of identical parts.
Injection Molding Applications
Injection molding is used in nearly every industry:
🚗 Automotive
- Bumper
- Dash components
- Engine covers
- Lightweight structural parts.
🏥 Medical
- Syringes
- IV components
- Surgical instruments
- Sterile containers
🧸 Consumer Products
- Toys
- Kitchen utensils
- Phone cases
- Appliance housings
⚙️ Industrial
- Machine housings
- Custom gears
- Industrial housing.
✈️ Aerospace
- Lightweight components
- Flame-retardant housings
- Cabin parts
Injection Molding Material Types
Depending on strength, flexibility, temperature resistance, and environmental impacts, your plastics manufacturer can help you choose the right fit for your parts.
Thermoplastics
- ABS (Acrylonitrile Butadiene Styrene)
- Polypropylene (PP)
- Polyethylene (PE)
- Polystyrene (PS)
Thermosets
- Epoxy
- Melamine
- Phenolic Resins
Elastomers
- Silicone Rubber
- TPU (Thermoplastic Polyurethane)
Specialty
- Glass-filled polymers
- Biodegradable plastics
- Medical-grade resins
Mold Tools - The One-Time Start-Up Cost to Scale
Before manufacturing your product, you will need to design and manufacture your custom metal mold, which will be the largest startup cost included in your project. Depending on the specifications, size part, and your lead times, tooling can take anywhere from 4 - 8 weeks!
What Influences Mold Cost?
- Complexity of the part
- Number of Cavities
- Material of the mold (steel or aluminum)
- Expected volume of parts
- Surface finish requirements.
After the amount of money spent on the mold, many people forget that if a mold is manufactured correctly, then it can be used a million times, making your investment economical!
How to Pick an Injection Molding Partner
Your plastic manufacturing partner will have a great deal of responsibility to deliver success on your project, so what should you be looking for?
1. Experience with Custom Plastic Fabrication
Look for a Las Vegas or local plastic manufacturer who has relevant experience in your industry, and look at their case studies and production portfolio.
2. Design & Prototyping Support
Do they offer one or more of the below:
- 3D CAD design?
- Rapid prototyping?
- Mold flow simulation?
- DFM?
At Welch Plastics, we can help to customize and adjust your design without spending money on tooling.
3. Machinery
The technology of injection molding machinery has continually improved, allowing you greater control of precision, cycle time, and part consistency. Be sure to ask specific questions about their machinery, automation capabilities, and capacity (what can they produce in a specified volume).
4. Material Knowledge
A well-established plastic manufacturer should help you with selecting the resin that meets your functional, cost, and sustainability preferences.
5. Quality Control Standards
Make sure your partner is ISO certified and has solid QC practices, including:
- In-process inspection
- Dimensional inspection
- Material traceability
- End-of-line testing
6. Transparent Pricing
- Get detailed quotes that include:
- The cost of purchasing the mold
- Per-part cost
- Setup cost
- Any secondary operations (printing, assembly, packaging)
- Steer clear of partners who low-ball bids but skimp on quality.
7. Customer Service & Communication
Select a partner that offers responsive communication, concrete timelines, and post-production support.
The Welch Plastics Advantage
Welch Plastics has established itself as a reliable plastic manufacturer in Las Vegas. Here are some ways we make your custom plastic fabrication or high-volume injection molding program easier:
✔ Custom Plastic Fabrication
From design to delivery, we handle all your project needs in-house!
✔ Industry Experience
We have served customers in the automotive, retail, consumer electronics, and even the entertainment industries!
✔ Customers We Service
- PX40/40 (Jose Canseco's power swing extender)
- Squirt Boards (launching 2025)
- Museum of Illusions
- Swift Slice (coming 2025)
✔ State-of-the-art Equipment
We operate advanced molding systems that produce high-quality parts while maintaining tight tolerances.
✔ Sustainability
We offer green resins and strategies to mitigate waste in the manufacturing process.
Trends Influencing the Future of Injection Molding
The injection molding industry continues to adapt and embrace change, and being on the leading edge of these trends will keep you competitive:
♻️ Eco-friendly Resins
Recycled and biodegradable plastic have become commonplace in responsible manufacturing.
🤖 Automating Processes
Increasingly, companies are using robotic arms and smart sensors to automate part handling and inspection.
🖨 Hybrid 3D Printed parts
Some companies are incorporating 3D-printed parts into their mold or using 3D printing to produce low-volume runs.
🌐 Smart Manufacturing
Industry 4.0 technologies are allowing manufacturers to monitor real-time performance, perform predictive maintenance, and provide more efficient operations.
Let’s Build Something Together
Are you ready to take your product to the next stage?
Whether your product is a prototype or you are commercializing a production run of 500,000 units, Welch Plastics, a custom plastic fabrication and high-volume injection molding manufacturer based in Las Vegas, is your partner.
📞 Let’s connect. Contact us to get a quote or start a discussion regarding your design.
We will work with you to take your idea from concept to reality with high-quality performance, precision, and support from a partner you can trust.
Welch Plastics is the exclusive manufacturer for Jose Canseco’s company PX40/40.
To order PX40/40, please use this link Improve Your Swing with Jose Canseco’s PX 40/40 Power Extender
Check out Jose’s interview about PX40/40
Some of our clients for injection molding services:
PX40/40 Improve Your Swing with Jose Canseco’s PX 40/40 Power Extender
Squirt Boards (website launching summer of 2025)
Museum of Illusion Museum of Illusions
Swift Slice (launching summer of 2025)
