Q - I would like to re-finish some outdoor furniture that has rusted. I read about sanding the rust off, converting the rust, and/or chemically removing the rust.
Which should I do?
Sandy in Atlanta
A- You have mentioned the three most popular ways to get rid of rust.
Here are the pros and cons of each:
Grinding/Sanding/Scouring - Pros: There are no pock marks and you will have a smooth surface to paint after you are done. You can also complete a project in a day, not having to wait for chemicals to dry.
Cons: This option is dirty, dusty, hard work which requires power tools and lots of elbow grease.
FYI - this will yield the best results.
Convert the rust - Pros: This is the easiest way to stop rust and prime in one operation and it is less expensive than chemical or mechanical methods for removing rust.
Cons: Converting rust will leave a pockmarked finish that will show through after you paint. Also the item will rust again sooner than if you had sanded it to begin with.
Remove rust with chemicals - Pros: Soaking removers will do all the work for you if the object is small enough (which a lawn chair would not be). Spray removers will greatly reduce the grunt work involved but will require several applications and you will still have to do some scraping.
Cons: Sometimes you will have to wait for a long period of time for the liquid removers to do their jobs plus you will make a huge mess. After removers work the surface will still be pockmarked and show through the painting.
A quick tip for lazy people - don’t think you can spray rust inhibiting paint onto a rusty surface and get good results. The rust will bleed right through the paint and ruin your new paint job.