Tolerance analysis in automotive body applications is well‑established. The figure below shows a DTAS model used to analyze front and rear door gaps and flushness.

The basic inputs for this tolerance analysis model are as follows: measurement point tolerance, measurement point target, assembly sequence, etc.

Basic Inputs

DTS Measurement Point Location Diagram

Assembly Process Details

Step 1 – Mount Door & Hinge to Fixture

•The door and half‑hinge are assembled on the door fixture table. 

•Positioning for the rear door follows the same method as the front door (see positioning points in the figure).

Step2: Door Side Hinge Assembly

The four door side hinges are positioned as follows:

Through the above steps, the door and door side hinges are assembled using a tooling fixture, forming a single assembly. The assembly is shown below, with the rear door as an example; the front door assembly is similar.

◆ Rear Door Sub-assembly

Step3: Side Panel Hinge Tooling

The front and rear door half-hinges connected to the side panel are assembled into a single assembly using a hinge tooling fixture. The following diagram shows the tooling's positioning points on the vehicle body.

Step4–  Side Panel Hinge Installation, Similar to Door Side

Through the above steps, all four body side hinges are mounted on the side panel using a tooling fixture. The assembly is shown below:

Step 5 – Install Front & Rear Doors

•Rear Door: Mounted to the side panel via the hinge pivot. Its rear end is aligned in the Y‑direction against the side panel using a magnetic flattening block. 

•Front Door: Mounted to the side panel via the hinge pivot. Its rear end is aligned in the Y‑direction against the rear door using a magnetic flattening block.

The diagram below shows the position of the Y‑axis magnetic alignment block for door positioning.

After the above installation, both car doors are successfully assembled.

The result is as follows: