At work years ago a welding supply place accidently send us a handfull of 'Zinc sticks'.

I didn't know what they were, so I asked & was told
"Its a stick of low melting temp metals, mostly Zinc & Lead & tin. You make a arc weld & then before it cooled down, rub the stick onto the weld. The metal melts & sticks to the weld, giving it a galvanised Zinc surface coating.
Its handy for repairing galvanising thats oxidised from salt air & galvanising welds that will later on rust. Or fixing welds on galvanised metals."



zilt sticks, zinc repair sticks


Instructions from a site> Methods of use

If the item to be repaired has just come out of the galvanising bath and hence is still hot, the stick can simply be rubbed over the area required.
If the item is cold The method for there use is as follows:
Heat up the area of galvanising to be repaired ( take care not to exceed 200oC as this will damage the galvanised surface).
Heat up the end of the stick with blow torch or similar until the stick starts to melt.
Rub the end of the stick onto the area.
Re heat the stick and surface as required < end.