[Shop-talk] painting steps with POR-15

[John Miller]

Rich White wrote:
> I need some advice from this knowledgeable group... We have a set of metal
> steps that need work.  These are heavy site build steps not the type you see
> on trailers.  The tread surface is diamond plate and was replaced last year.
> Nothing was done to protect them after the repair.  I was thinking of blasting
> them and then painting them with POR-15 this summer.  Is this a good idea?

Things to consider:

a) POR-15 is tough stuff, but...

b) It sticks well to rough bare-metal surfaces, poorly to smooth bare 
surfaces, not at all to other coatings.

c) The standard black POR-15 disintegrates within a few days if left 
exposed to solar UV.

d) Topcoating POR-15 basically has to be done while it's still tacky; if 
you wait until it's hard NOTHING will stick unless the base POR-15 is 
abraded enough to provide 'tooth' (in your case that might require a 
lightly-abrasive blasting of the cured surface.)

e) In your application I'd be concerned that the topcoated surface would 
see enough wear that it'd leave the base POR-15 exposed, which would 
then begin to peel.

John.