That was what I was after. I made patches from some school grade foam board but they need to be backed up with something then sealed.It could reinforce the reattachment of broken pieces,
So just use tape on the back side and resin on the fabric side. Makes sense. I looked up gaffers tape but it says it is waterproof on the backing so not good for resin? Or am I looking at the wrong stuff? Either way I think my industrial duct tape on the back side will hold the resin from soaking through. Then I can seal with resin. And for a large broken repair area then maybe a local layer of glass mat on the fabric side for good measure. Then layers of resin until it doesn't soak in any more? I am beginning to see this working.My question though is why need the mesh at all? Just a cloth-reinforced duct tape on the reverse side of the headliner does wonders, followed by resin alone on the now held firm front side. If need be, use some of that cloth tape called gaff tape/gaffers tape on the side you want to resin impregnate. Picture duct tape made of cloth with glue on one side. That stuff the resin can soak right into since it's not a plastic base like duct tape is.