galvanising a building

[tomlad]

Cheers
Id thought I might have to have it blasted first

 

[MD @Minshall Buildings]

correct.....rust is not really an issue for galvanizers ( unless its very old and pitted from heavy rust) its contaminations on the surface of the steel that cause issues.., like paints, oils, varnish, weld slag.

Remember also, if you are using an anti spatter spray make sure its a water based one!

 

[tomlad]

and every boxed in bit needs one hole drilled ... 6 mm ??

 

[dannewhouse]

and every boxed in bit needs one hole drilled ... 6 mm ??

atleast 2 holes one for chem to go in/out and one for air to go in/out.
ideally bigger than 6mm aswell?

 

[MD @Minshall Buildings]

rule for holes is as large as possible, directly opposite at the end of each sealed section and as close to the end as possible. The larger the holes the quicker the fabrication will fill up, sink and subsequently drain....all important for producing a good quality galvanized finish.
If you imagine each section needs to allow acid and then zinc to flow through all of the internal sections, then it becomes quite easy to work out where to drill holes.