The aluminum threshold at our entrance door had concrete splashed on it when the new walk was installed. Most of it was wiped off but there is still some there that does not look very nice. Is there a way to clean if off?
1. When placing concrete near siding or door entrances you should always mask with poly first.
2. Concrete has lime within it's composition and the lime will bite into raw aluminum or painted sidings. A light sprinkle of water over all surfaces near where the concrete is going to be laid will make surfaces easier to clean off.
To remove the concrete splashed on you threshold mix a solution of 1 part muriatic acid to 3 parts water. WEAR PROTECTIVE EYEWEAR AND RUBBER GLOVES. Dampen the surface with water using a sponge. Apply the acid/water mixture and let sit 2-3 minutes until it foams. Scrub with stiff brush, repeat until the concrete has been removed.
Rinse well and allow to dry. Then take acetone thinners and with super fine steel wool clean the threshold until bright shine returns. Rinse well and allow to dry. Polish with aluminum/chrome automobile polish