(San Jose, Costa Rica)
Is a FAA Form 8130-3 needed for a refurbished sidewall panel that has been repaired and recovered with new liner?
A record of work performed and a maintenance release are required when performing maintenance on an aircraft. Reference FAR 43.9 - Content, Form, and Disposition of Maintenance Records
If you perform the work on the sidewall panel as part of the overall work being performed on the aircraft during the maintenance visit, then a record (work order, work card, non-routine card, etc) of that work performed is all that is necessary. When the work on that aircraft is finished, a release to service will be issued that would include the repair of the sidewall. Neither the work performed or the release has to be on a FAA Form 8130-3.
The same would be true if the panel was sent to your shop from an outside customer. However, even though not mandatory, the use of the FAA Form 8130-3 has become an industry standard for documenting the work performed and the release of that work.
Note: In the case of the sidewall panel refurbishment, there should also be documentation from the vendor of the material used certifying compliance with the material flammability requirements for compartment interiors.