Disassembling Riveted Diecast
Technical procedures for rivet removal, depth-calibrated drilling, and threaded reassembly.
For collectors and customizers, the factory rivet is the primary barrier to interior detailing, wheel swaps, and restoration. Because diecast cars are held together by mushroomed zinc-alloy posts, disassembly is a subtractive mechanical process. Success requires precise depth control to prevent puncturing the car body and concentric alignment to allow for a threaded reassembly.
1. Technical Tool Specifications
Using standard high-speed power drills often generates enough friction-heat to melt plastic bases or snap brittle zinc posts. Professional results require low-RPM precision bits.
2. The Two-Stage Drilling Progression
Removing a rivet is not about drilling through the car; it is about shaving off the flange that holds the base in place. Follow this drill bit progression for a factory-clean finish:
| Bit Size | Technical Purpose | Maximum Depth |
|---|---|---|
| 1/16″ (1.6mm) | Pilot Hole: Centers the drill path for the reassembly screw. | 3mm – 4mm |
| 9/64″ (3.5mm) | Flange Removal: Cuts away the “mushroom” head of the rivet. | Surface level only |
| 5/64″ (2.0mm) | Tapping Prep: Opens the pilot hole to receive the M2 tap. | Match screw length |
3. Step-by-Step Disassembly Protocol
- Marking the Center: Use an automatic center punch to create a small dimple in the center of the rivet. This prevents “drill walk.”
- The Pilot Cut: Drill the 1/16″ hole. This hole must be perfectly vertical. Use a depth-stop or a piece of tape on the bit to ensure you do not hit the car’s hood.
- Popping the Head: Switch to the 9/64″ bit. Drill slowly until the ring of the rivet head separates from the post. The chassis should now lift away freely.
4. Tapping and Threaded Reassembly
To maintain the value of the model, do not use glue. Instead, thread the post using an M2 x 0.4 Tap. This allows you to use Button Head Hex Screws which look identical to factory rivets. This “Restomod” approach is the current standard for premium 1:64 scale custom work, as it allows for future maintenance without further drilling.
Technical FAQ
This is usually due to excessive lateral pressure. If a post snaps, you must “pin” the repair by drilling a 0.5mm hole into both pieces and inserting a piece of steel wire before epoxying. This restores structural strength.
Plastic rivets (common on some modern economy brands) should not be drilled. Use a Soldering Iron to gently melt the head, or a sharp X-Acto chisel blade to shave the head off. Plastic rivets can be “re-mushroomed” using heat during reassembly.