It is far too cold in my workshop to use the POR-15, which I was hoping to test out today. The small print says that it must be applied in temperatures of between 50-90degrees F (or 10-38 deg C)....and my fridge thermometer shows it well under 10degC ("Well don't do it in the fridge then, you plonker", said John). I don't want to use my halogen heater to raise the temperature because I don't want to reduce the humidity (good for curing the preparation) and am not sure I'd want to leave the heater on unattended for 5 hours (minimum)....so I will need to wait for warmer weather.
What I have done is bought a starter kit from Frost - I'll buy more if the stuff is as good as I hope. My van has a lot of small areas where metal has been eaten by tinworm...in sills etc....where a bit of POR-15/Porpatch could work wonders. POR-15 is a rust-preventative paint designed for application directly on rusted areas, which dries rock-hard and prevents rust from re-occurring; PorPatch is a waterproof filler (a thicker version of the same stuff) which fills, adds strength and prevents rust.
I plan on using the application, principally, in the guttering around the front panel, beneath the winscreens. Tinworm has eaten along the base of the nose below the windscreens so I cut access holes in the channel inside the cab and welded reinforcing fillets and tacks behind this area.
I also intend using it in the crack which runs down the sides of the front panel frame.
Today I shall brave the cold and put the last of the weld reinforcement behind the nose panel - those rectangles under the windscreens-, where they meet the gutter radius (tucked out of view under the red line). Then I shall start prepping the metal from the Goat Lady's van ready for welding around the windscreen inside the cab.