I did a test yesterday using Phosphoric acid to prep some parts for primer and since I've never done this before I didn't know what to expect and I have questions about the results.
The instructions on the container list two ways to use it.
In this
FIRST TEST I applied the acid full strength and let it sit overnight according to the instructions. As you can see, this part has some deep rust pits. This morning I rinsed the part with water and sanded a portion of the treated area. Am I to assume that the gray material left down in the pits is an inert material that can be primed over without any further treatment other than a wipe down with grease and wax remover?
In this
SECOND TEST I applied a diluted solution (2:1) to sandblasted clean parts, let it sit for 20 minutes, rinsed it with water and hung it up to dry, and this is what have this morning. Is this right? Can I primer right over this? It sure looks like rust to me.
Any input is greatly appreciated.
Thank you.
