Really Painting our Launch rods would be a total waste of time and materials. our Exhausts are pretty corrosive and would eat up even HI-Temp engine paints.
Instead Replace your Steel launch rods with either 304 or 316 Stainless steel: Drill rod precision is totally unnecessary. Our Hobby launch lugs have Plenty of room to handle the slight variances in rolled stainless rods.
I started using 304 Stainless 1/8",3/16" and 1/4" launch rods back in the early 80's. I'm still using the same 1/8" and 3/16" rods purchased back then.
Since that time I've switched all our clubs launch rods to Stainless (mostly 304) for the smaller stuff and 316 Alloy for 1/4" x 72" and larger. 316 which is a good bit stiffer.
The beauty of Stainless Steel is they clean up with a squirt of Fantastic cleaner and stay well lubed with a finishing whip down with a paper towel sprayed with WD-40.
McMaster-Carr is a fine place to purchase these rods. Currently:
304- unpolished-not certified:
1/8" #89535K16 3' @ 5.04ea, 6' @ 8.55ea
3/16" #89535K84 " @ 5.52ea " @ 9.36ea
1/4" #89535K85 " @ 9.43 ea
316- Not Certified:
1/8" #89325K88 3' @ 7.45ea, 6' @ 12.62ea
3/16" #89325K89 " @ 7.64ea, " @ 12.95ea
1/4" #89325K91 6' @ 13.48ea
Plus shipping which can be anywhere from about 10buck or the 3footer to 17.80 for the 6' They come in 3" tubes.
PS: If you want to make your Launch rod Rally sparkle: Chuck one in your electric drill and spin it while running some 600grit sandpaper or better a Ultra fine Grey ScotchBrite Pad #7448 up and down the length for a couple minutes. really brings out the Shine of either Stainless Alloy.
I do this with all the clubs & my Launch rods when they come in New or every couple years just to brighten them up.