finishing polished steel?

[sandbert]

Hi folks, I seek your wisdom in finishing a steel surface so as to prevent rust and preserve a bright polish. I'm making a table with the legs/frame of 2x2 square mild steel and the top of cherry. What I'd like to accomplish is to polish the steel to a bright finish and then apply something so that finish stays that way, basically the look of stainless. Why not just use stainless, someone may ask? A: because it's expensive, I'm still a novice and I want to work out my techniques and make my mistakes on the cheaper material. Since the look of the steel is part of the finished piece this is also the project where I'm teaching myself how to polish out a weld so that it's invisible. So far I've had excellent results with a 50 grit sanding disc and a 80 grit flap wheel. Any suggestions about that are also very welcome. If this all works out I'll try a similar project with stainless and teak for an outdoor table.
Anyway, some kind of clear, durable finish to keep the steel from rusting? Anything oily that would rub off on clothes, kids, dogs, etc. won't work. It seems there are products out there but I have no experience with them. Perhaps just a good rubbing with an auto wax? Any suggestions will be much appreciated, and everyone have a great holiday season.

[raferguson]

You could buy clear acrylic at the hardware store, I think that Krylon makes some.

I use Permalac as a clear coat, but that is not widely available and fairly expensive.

I would not use wax or oil except maybe wax on top of the clear coat.

Be sure to use solvents of some kind, even alcohol, to remove fingerprints and oils before you spray.

For the kind of project you are doing, I would typically use maroon (medium) scotchbrite, which is somewhat comparable to 120 or 150 grit, and run it back and forth along the length of the tube, hand sanding, so that the lines/grain of the sanding run along the length of the tube. If I did not have maroon scotchbrite I would probably go for 150 grit sandpaper. I have been known to power sand with 240 grit paper to get rid of all the coarse sandpaper marks, and then go back with maroon scotchbrite to get the uniform finish that I want. Sanding fine and then medium sounds crazy, but it works if your goal is a uniform linear finish.

A somewhat different finish is the random orbit finish, which I also like, especially on large flat areas, but it sounds like that is not what you have in this case. At this point I have pneumatic random orbit sanders in 2 inch, 3 inch, and 6 inch disks.

[Cgotto6]

Yep clear acrylic, or clear lacquer spray. Like Deft or similar. Rust oleum makes an equilivant at Home Depot I know.

[sandbert]

Thanks for the suggestions and tips. Something like a spray on acrylic had occurred to me, I was wondering how it's long term adhesion would be. But it says it's for application on metal. I'll try some out on a test piece.

[Cgotto6]

I use the stuff I mentioned on steel that I blacken with patina. I was just in a house I built 6 years ago, had a handrail system I did with steel I blackened then hit with the rust oleum clear acrylic and it looks as good as the day I finished. No hints of rust, obviously being indoor helps but I have had good luck with the longevity.

[raferguson]

There is a huge difference between inside and outside. Inside, a clear finish is likely to hold up, if you can keep it away from cleaning chemicals, etc.

I understand that there is no clear finish available on the planet that will hold up for years out of doors, exposed to the sun. Don't kid yourself that clear will hold up out of doors. Hot dipped galvanized is good out of doors. ;-)

[Cgotto6]

I doubt his cherry topped table will be sitting in the sun or weather. But yes I agree, galvanizing is good for exterior use.