Mazda MX-5 Side Panels and Sills Restoration – Professional Rust Removal and Durable Repair

Date 13 March 2025
Category
Mazda
Mazda MX-5 Side Panels and Sills Restoration – Professional Rust Removal and Durable Repair

Why do Mazda MX-5 models suffer from rust on the side panels and sills?

The Mazda MX-5 is one of the most popular roadsters in the world, but it’s also known for its susceptibility to rust, particularly on the side panels and sills. This problem is especially common in older models and can cause serious structural damage without timely repair.

At LucaCarMods, we have extensive experience in repairing rust damage to side panels, sills, and chassis rails. In this article, we explain where rust most commonly occurs, how we professionally address this problem, and why our method is the best long-term solution.

Common rust spots in different generations of MX-5

Depending on the type of Mazda MX-5, we see different rust-prone areas:

Mazda MX-5 NA (1989-1997)

  • Side panels: Rust often starts at the bottom near the wheel arches.
  • Sills: Especially behind the front seats and towards the wheel wells.

Mazda MX-5 NB NBFL (1998-2005)

  • Side panels: Rust formation along the wheel arch and lower edge.
  • Sills: Primarily at the bottom and towards the rear wheels.
  • Chassis rails: Extra susceptible to rust due to the two-layer design.

Mazda MX-5 NC (2005-2015)

  • Sills: Rust mainly occurs on the rear sills.
  • Wheel arches: Often starts as small blisters in the paint and spreads.

Increasingly, we’re seeing that not only the outer sills, but also the center sill and sections towards the front need to be replaced. To ensure the highest quality, we have taken various sheet metal parts into our own production.

Sheet Metal Parts

How do we assess the damage and determine the costs?

Before we start a repair, we always first conduct a thorough inspection of the rust damage. This can be done via:

  • Photos that you can send to us.
  • An on-site appointment for a comprehensive check.

When the car has been repaired before, assessing the damage can be more difficult. The quality of previous repairs determines how much rust returns within a short time.

We have seen the most striking and poor “repairs”, including:

  • Cardboard and silicone sealant as filler.
  • Kilos of body filler smeared over rust without proper repair.
  • Parker screws and pop rivets to secure panels.
  • Poorly welded panels without rust protection.

These types of temporary solutions may seem cheap, but lead to even higher costs and structural damage in the long run.

Our Repair Method – Thorough and Durable

Our approach is distinguished by complete rust removal and preventive protection.

Step 1: Removing all rust and poor repairs

  • We remove all spot welds and cut away all rusted parts completely.
  • If necessary, we remove not only the outer sill but also the center sill and inner structure.

Step 2: Welding high-quality replacement sheet metal

  • We use self-produced sheet metal parts, Klokkerholm sheet metal, and original OEM Mazda parts.
  • All panels are welded against each other (not on top of each other!), so no moisture can get in between.
  • After welding, we grind the weld seams flat and smooth and apply an anti-corrosion primer.

Step 3: Maximum protection against future rust formation

  • Exterior: Coated with a 2-component polyurethane (PU) coating for optimal protection against stone chips and moisture.
  • Interior: Treated with a cavity wax, so that every part is protected against moisture and condensation.

Photo report of each repair

Every repair is documented with an extensive photo report, so you know exactly what has been done. This offers complete transparency and guarantees a quality repair.

How long does a side panel and sill repair take?

The required time depends on the damage:

  • Small rust repairs: 2-5 days.
  • Welding new side panels (both sides): 1 week.
  • Complete restorations: 1 to 2 months.

What does repairing a side panel or sill cost?

The costs vary depending on the damage. As a guideline:

  • Side panel and sill repair: From €1500 per side.
  • Complete restoration: Upon request.

Although this is more expensive than at an average garage, we don’t just weld a plate over it – we ensure a structural and lasting repair.

Maintenance tips to prevent rust

  • Clean the wheel arches manually with every wash to prevent dirt accumulation.
  • Remove leaves and dirt behind the side panels – these can be easily detached with three bolts at the bottom.
  • Check and renew the cavity wax every 5 years for maximum protection.

Make an appointment for professional repair

Don’t wait too long to have rust repaired – the longer you wait, the worse the damage becomes.

📅 Make an appointment? Contact us by email or phone.
📩 Send us photos of the damage for an assessment.

🔗 More information and schedule an appointment via our website: LucaCarMods.com