What's the best way to get spray paint to stick to a floor on a aluminum boat?

I've tryed lightly sanding the floor so the paint has a little more texture to stick to and it still wont stay after about 2 months? can anyone help me please?What's the best way to get spray paint to stick to a floor on a aluminum boat?
Have you thought about putting bedliner material on your floor. It is non skid, tough and looks good.Spray-on or roll-on works equally well.What's the best way to get spray paint to stick to a floor on a aluminum boat?
The best way is to clean the floor with an acid like hydrofluoric, I have had good results with phosphoric and citric as well - use full safety gear particularly goggles and rinse off very well. Allow to fully dry and fully but lightly coat with an etch primer - you should be able to see through it. I use two pack epoxies - but painting is one of my trades. You can get chemically induced asthma and dermatitis from exposure to epoxies and iso cyanates - don't allow to get on your skin! I use sugar in the top coat as a grip maker. Just hose off the sugar after the last layer cures and you have an excellent soft grip - the finer the sugar the finer the grip. Lesser coatings like enamel and so on just are not tough enough to survive for long. On no account put any coverings on the floor that can allow water to lay underneath them - your deck will dissolve in interestingly expensive ways.





The surfaces that are walked on are the only ones that I like to paint, alloy has a self protecting oxidising layer that quickly forms naturally and is very stable and self healing. Coatings can allow extensive corrosion to occur before any external signs are visible. But that's the opinion of a commercial fisherman where practicality is far more valuable than some fashion statement.
They have an acid base primer wash for aluminum boats to prep for painting. If it was a clean and previously 'unpainted' boat; you could spray it down with plain vinegar. It will clean and slightly etch enough to sustain a decent paint job. I have done this a number of times with good success. Also, epoxy paints are more adaptable to sticking on clean aluminum than an oil base or alkyd paint. Don't paint epoxy over old existing paint though. One response that I noticed is a good one. It stated to use truck bed liner paint. I too have seen this and it did look good. I have no experience with doing this in a boat though. It sounds like it would work well.
forget the paint and use marine carpet. safer and quiter.
You need to prepare the surface with an etching coat. Even then it can still chip, but it will last reasonably well.