Language

Home > News > Learning from Errors: How We Handle Less Qualified and Unqualified Products

Oct.2025 29

Learning from Errors: How We Handle Less Qualified and Unqualified Products

Introduction

In this article, we'll walk you through how we handle unqualified products, detailing our robust rework and scrapping process. By the end, you'll have a clearer understanding of how we supervise and monitor product quality at NTP, as well as insight into common carbon rim defects and how they affect overall quality.

Details

At our carbon rim factory, every product flaw is an opportunity for growth. In particular, paintless products—those without a layer to hide imperfections—are critical in driving continuous improvements in our production process. Each less-than-perfect rim teaches us valuable lessons, pushing us to refine both our craftsmanship and quality assurance systems. The ultimate goal? To produce nearly flawless raw rims straight out of the mold.

Less Qualified Products: Focus on Aesthetics

We define less qualified products as those with defects that don't affect the product's functionality but may impact its visual appeal. These imperfections are often purely aesthetic, but they still require attention to ensure that the product meets our high standards.

Common Defects in Carbon Rims

To break things down clearly, we’ll dissect a carbon rim into three main sections: the rim bed (center channel), rim beads, and rim walls. Some manufacturers refer to the rim bed as the "small C" and the sidewall as the "big C" because of their distinct shapes and relative sizes.

Section	Defects	Causes
Rim Bed / Center Channel (Small C)	Overly abraded, scratches and scuffs	Improper sanding paper; lack of experience
	Color difference	Excessive sanding; lack of painting expertise
	Thick, rough mold parting line	Inadequate sanding; mold wear and aging
	Pinholes	Material, layup, molding.
	Burrs around spoke holes or deformation (not round); paint accumulation near the hole	Lack of hole treatment and inspection; drill bit wear; excessive paint
Rim Beads	Uneven abrasion or insufficient resin coverage on rim beads	[quite complicated] Improper sanding, layup, molding operation; materials
Rim Beads	Rough parting line on rim bead edges	Insufficient sanding; mold wear
Rim Walls (Big C)	Uneven sidewall	Mold wear, material, layup, molding.
	Blackened sidewall with no color transition (unless client requests)	Lack of painting expertise
	Burrs and paint accumulation near holes	Improper drilling; excessive paint
	Mold parting line at holes not smooth	Mold wear; improper treatment
	Pinholes	Material, layup, molding.
	Paint marks	Residue from release agents or other oily pollutants
	Water marks	Environmental moisture exposure
	Sand marks	Incorrect sanding materials or technique
	Pollutants	Improper mold cleaning or room cleanliness
Decals & Stickers	Decal pollution; cracks or peeling	Excessive heat; poor-quality materials; improper treatment

Unqualified Products

Unqualified products are those where defects affect functionality or safety. These flaws are much more serious and require our full attention. Whether a product is raw, partially completed, or a returned unit, we meticulously evaluate how each defect impacts performance before deciding to repair or scrap the item.

Common Flaws & Criteria

Defects	Area	Failure Criteria
Excessive Abrasion	Overly abrasive rim beads	Rim trueness exceeds 0.5mm
Excessive Abrasion	Overly abrasive rim bed/center channel	3+ layers of carbon are affected
Voids	Sidewall voids	Large voids (>1cm) or multiple smaller voids in critical areas
Voids	Braking track voids	Any voids detected.
Wrinkles	Waved fibers	Waved fibers exceeding 10% of surface area
Hole Drilling Issues	Incorrect hole dimensions/number/angle or deformed holes	Wrong hole drilling program; improper operation

Our Rigorous Product Rework and Scrapping Process

At NTP, quality control is our top priority. Our rework and scrapping process ensures that all products meet high standards for both aesthetics and functionality. Here’s how we handle less qualified and unqualified products:

Step 1: Identification and Notification
Once a defect is identified, the responsible team records crucial information—such as product model, production date, and quantity—and alerts our QC technician for further assessment.

Step 2: QC Assessment
The QC team evaluates the defects, checking whether they meet our internal scrapping or repair standards. Products marked for disposal are sent to a designated scrapping area, while items that can be salvaged are flagged for rework.

Step 3: Rework or Reproduction
Defective products that can be repaired are sent to the appropriate area for rework, while those deemed unrepairable are scrapped according to our guidelines.

Step 4: Scrapped Product Analysis
Scrapped products are carefully examined by engineers. We cut and sometimes burn the rims to inspect internal layers, identifying the root causes of the defects. An analysis report with suggested improvements is created and shared with both the QC and production teams.

Step 5: Continuous Improvement
Our engineering and QC teams collaborate to implement improvements based on the scrapping analysis. Regular follow-up ensures that corrective measures are applied effectively.

Step 6: Rework Analysis
At the end of each month and quarter, our QC team reviews the most common defects, shares findings with the engineering and production teams, and adjusts the manufacturing process to reduce rework rates.

Through this meticulous rework and scrapping process, we’re able to maintain consistency and quickly address any abnormalities that arise in production. This attention to detail ensures that we deliver products that meet the highest standards of quality.

If you’d like to learn more about our quality control process or are interested in seeing it firsthand, we invite you to visit us in Xiamen for a factory tour!

How to Design and Test the Package for Your Rims and Wheels

XC New Product Project: The 32-Inch Future is Coming Sooner Than You Think

About Us: Our Story; Our Team

What We Offer: OEM vs ODM Service; Open Mold Products; R&D and Technology; Quality Control

Get In Touch: Floor 3, No 19 Baihuyan Road, Xiamen, Fujian 36102, China

Email: koko@ntpcomposites.com
Drop a call: 0086 137 9925 1201
What's app: 0086 156 5978 9571

BOOK A FACTORY TOUR

NexusTech Prime (NTP) Composites

Established in 2013 initially as an OEM carbon rim contract manuafacturer, NTP composites has grown steadily to be a full-service OEM and ODM service provider, with brilliant quality control, proficient engineering capability, and excellent customer service.

Get Your Custom Quote in 24h

Full Name*

Phone No

Email*

Message*

We use Cookie to improve your online experience. By continuing browsing this website, we assume you agree our use of Cookie.