Hi guys. I'm new to custom DIY car audio and was wondering if anyone can help me out. I'm going to be constructing a fibreglass sub box in my ute behind my seat. The box will be moulded onto metal and sit up hard against it when built. I was thinking of putting sound deadening between the box and the metal to stop vibration. Question is should I put the sound deadening on first and fibreglass mould over it or should I fibreglass first and sound deadening after? If I sound deaden first, will it pull off when I remove the mould? I'm going to be using painters tape to stick the fibreglass onto. I'm going to be using dynamat and have been told that its really sticky and shouldn't pull off. Thanks in advance for any advice.

 

Sound deaden the metal after youve created your box you can put a layer on the box and the surface

 

Good luck with the build! post some pics when your done