Carbon Fiber Repair On The BMW i3

The magnets that temporarily hold the backing plate are extremely strong and must be used to complete the repair.

On the BMW i3 with the carbon fiber passenger cell, the question is often asked, how do we repair damage to the carbon fiber? For that answer BMW presented an overview of the repairs at the 2014 SEMA show. The simple answer is that you cannot repair the passenger cell the way that you would repair a sheet molded compound (SMC) part.

Even a scratch to the carbon fiber passenger cell is not repairable unless it meets specific measurement requirements using an inspection tool from BMW. If the part is scratched deeper than the maximum depth then the part will have to be replaced.

To replace parts of the damaged carbon fiber passenger cell BMW has specific procedures for replacing the damaged parts. Take the outer rocker panel for example; BMW has created a sectioning procedure for the outer rocker panel.

To perform this procedure there are specific cut locations much like a steel panel. The replacement part is then installed using a supplied backing panel, adhesive, and specialty magnets to hold the backing plates until the adhesive is cured.

For more information on the special tools and procedures visit

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