okay what I'm going to show you next is how to acid etch aluminum and steel if you're if you're coating an aluminum boat with tough coat I highly suggest that you acid wash it instead of grinding sanding it's faster it gets a better more equal penetration into the metal it's just a lot easier and that's what we recommend aluminum deck any aluminum surface I recommend acid washing first any steel especially with rust on it you want to acid wash first a lot of people like to grind it and grind all the all the mill scale off the steel the the mill scum and everything the blue is it's hard to stick to so when we put our primers on that we want a good surface to bite into so I'm gonna wear rubber gloves because it is muriatic acid once again the muriatic acid you can purchase at a pool store or a home depot very simple to find very simple to use you might want to wear a mask I'm just doing a demonstration I'm just gonna pour it on it's what you do is you pour the acid on straight and I like to take a scotch brite and kind of rub it in and you can see the acid starting to work starting to penetrate into the aluminum surface this is a lot better than grinding or sanding see that white how it's turning white right there that's what you want I just lightly rub it in with a scotch-brite pad bare gloves it eats into the aluminum what it does it creates a microscopic edging which our primer sticks to wonderfully it's gonna rub it in once again if you're doing a Lumina boat this is a lot easier a lot easier than trying to grind and sand the whole thing next we're gonna do is we're gonna rinse the rinse the muriatic acid off of this rinse the dirt we've rinsed the aluminum it's etched it's ready for the tough coat primer the MP 10 is what you're gonna put on aluminum next what we're gonna do is we're gonna do the steel we're gonna do it in the same manner you just pour some acid on and it's gonna eat all that rust and it's gonna get all that mill scum out of there one thing you want to make sure you do when it does start sizzling you don't want to breathe it so you stand - you know upwind or get a mass but you just rub it on in the acid starts working so if you've got a set up of steel steps a steel boat if you have a ramp or if you have any kind of steel that you're coding a dock a rail what-have-you acid wash at first it's easier you can see the steel starting to turn white see that the acid it's eating all the mill scum off the steel I don't have a grinder I don't have a bunch of dust and steel flakes everywhere I just let the acid do its job it's eating all the rust off a little more on there some of this acid is diluted already but you can see how it's turning it white that is ideal for any primer and any coating the only other alternative to muriatic acid is to shop blast this is simpler less expensive you can do it yourself you