temp repair to steel hull using epoxy & fibreglass matting?

[conachair]

Found some unwelcome rust inside of the transom in lazerette and now have pinhole approx 1' above waterline. Rusty bit is about 2' high by 1' wide, all above waterline (pinhole's at the bottom of the patch). Ultrasound showed down to 1.1mm in places. Rest of the area seems pretty resilient to thumping with a hammer. Don't really want to get a new piece welded round here so question is - Has anyone tried epoxy and fibreglass matting as a temp solution for such a problem? Or any other thoughts?
Ta

[DeepFrz]

Sure, should work fine. Just make sure it's temporary. Be sure to prep the area well and taper the cloth out well past the rusted piece.

[conachair]

Thanks, offending area above. Hole is at the bottom just in front of the wire brush.
I've already cleaned up the rust using anglegrinder and wire cupbrush (fun that was!), then cleaned with strong detergent followed by por-15 metalready (zinc phosphate/phosphoric acid?) then after several good rinses and a really good dry (fan heater)put 1 coat of interprotect. Seems to be adhering well but you can see some of the existing paint where there was no rust bleeding through.

[David M]

I know its too late now, but for future reference, get rid of all the rust and just use an epoxy barrier coat like Interlux 2000 and then some epoxy filler. Obviously, get the boat hauled out ASAP and get the problem fixed by a good welder. Dont be tempted to weld one plate over the other. The area has to be cut out, a new plate put in the cut out area and then the new plate needs to be welded on both sides.