Technical Smoothing 32 Stanchions

What are your suggestions on smoothing these Brookville cast 32 roadster lower stanchions slick enough to prime and paint semi gloss black?
Who has done it? What is best?

A mini belt sander?
Roloc discs?
By hand?
All of the above?
All with progressively finer grits, of course.

Thanks!

 

Depending on how good your hands are; 2" & 3" roloc discs; then progressive grit paper on various shaped sanding blocks.

 

I'd do it all by hand to keep it flat. I'd start with files to smooth the casting pebbles then block sand with progressively finer paper. Disclaimer: I always do things the hard way.

 

Thanks for the advice.
That shiney spot is where I tried a Scotchbrite Roloc.
Just worried about not staying flat, and the surface getting waves.
I guess pretend that it’s body work and block it. At least they’re small.

 

Files and sandpaper on blocks. Slow tedious work. Power tools help speed the process but if you are not proficient (done a 100 hours or so on each step) the hand work is the way to get the finish you want.
If you are going to paint them high fill primer stick to the pebbly surface well.

 

Yes they will be painted, like stock Henry.

 

This first, then 2' rotolocs in the spots it couldn't reach, Dremel around the holes and tight stuff and then hand sand to finish. If you like to build stainless exhaust pipes, you need this.

 

I say by hand it's cast br*** should smooth out quickly. Just put your favorite album on and enjoy

 

Bill, I let the platers do it, most of the time they prefer to do the metal prep before chrome plating anyway. HRP