Vinegar for mill scale, Test!

[Doug Gray]

Hey Guys I want to talk tonight about mill scale on the Plates of the 3" Machinist Clamp Kits. Here is a shot of one of my clamps. The plates edges here were deburred with a fine file and a fine stone. Then cleaned up by hand with a scotch bright pad. Not a scotch bright wheel on a grinder, just a pad by hand. I wasn't trying to get the scale off. To my eye this finish is quite appealing, and you get a nice patina along the edges, that like a fine wine, will ripen nicely with age and use.

But that is just me. Some people want to remove the scale, so I've prepared a test.

We'll try two sets of plates, ones that are fresh of the laser table, just wiped down with acetone as a degreaser,

and a set that has been deburred, gentle scotch bright pad and had the holes drilled and reamed.

They got completely submerged in vinegar at 3:30 this after noon. the vinegar is 5% acetic acid by volume. I put an air tight lid on the "tank", I will agitate them periodically over the next 24 hrs and we will have a look tomorrow.

Video here

Let me know your thoughts, Maybe just 24 hours is to soon. We'll see!

 

[Ulma Doctor]

vinegar is a relatively weak acid, it will remove mill scale in time.
i'm not sure how much scale will be removed in 24hours, that will be interesting.
24hours removes most rust
it will also etch metal if given sufficient time

 

[Ulma Doctor]

nice looking clamps too!