[prkaye]

I bought a piece of 1/4" steel plate from a scrap metal place, to use as a back-riveting plate. It is covered with a thick coating of black corrosion.
Does anybody have any suggestions to effectively remove this? Tonight I tried sanding it, scrubbing with everything from CLR, to Paint-Thinner, to WD-40. Lots of it comes off, but after an hour there's still a thick coating on there.

 

[alpinelakespilot2000]

Take it to a machine shop and ask them to "grain" it. Should take about 10 minutes and cost about $10-15.00 if it's not too big.

 

[cytoxin]

HE IS ON THE MONEY

the machine shop is the way to go i did however do a 4x4 angle i bolted to the side of the table and i used a side grinder with 36 grit then 80 then 320 believe me the machine is the way to go. you'll spend more than that on sanding discs. after that i let the machine shop do the 8x16 piece for me..