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Repairing the Grid
Items Required:
Repair paint
defroster repair paint (This is typically a small bottle of conductive epoxy paint, often colored to match the color of your defroster grid, in a kit with a small brush and piece of cardboard with a slit in it. Most auto parts suppliers (including WalMart, KMart, etc.) have these, and kits can also be obtained from JC Whitney. The usual cost is about US$10. I've repaired well-over 50 breaks using a single small bottle of paint (although I had to add some acetone to thin it when it began to dry out.)
masking tape (This is preferable to the cardboard paint guide included in the repair kits, both because you can repair a number of areas at the same time and because the slits in the cardboard are typically much wider than the grid elements.)
a razor blade (This is used to trim the edges of the repaired grid elements, where the new paint will have a tendency to wick out from the grid. It can also be used to remove the felt-tip marker or crayon elements.)
acetone (This is used to thin the paint, which will often begin to dry out in the bottle very quickly. It is only required if you have a number of repairs to make, which allows the acetone in the paint to evaporate.)
a large piece of white or light colored cardboard or cloth (This is used to enable you to see the grid elements more clearly.)
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