Brick patio cleaner (Hydrochloric)  will shift it as well a smill scale on black (hot rolled) steel

Don't put it in when red hot, ideally let it cool until you can touch it, quench in water first if in a hurry.

After soldering

10mins in the brick cleaner and just a gentle scrub with an old toothbrush.

Edited By JasonB on 26/06/2016 20:42:41

The mill scale I find needs about half an hour.

Soldering will depend on how long you were heating and the exact steel used. Just watch the first bits you do to get a feel for it and give a rub with the brush to see how it is going. Overnight and you might see a slight loss of material so don't forget its in the pot.

It also removes the more stubborn Tenacity5 or HT5 flux which normal pickle does not shift very well.

Rinse it off well and get some oil on the surface as it will rust quickly afterwards. Also best not done or stored inside the workshop as the fumes will rust other metal.

Another example

Jason, could you give us a bit of an idea on the scale of those photos i.e. dia/thickness of the large disc. Is the vertical shaft butted onto the disc, or is it in a hole? What power burner (gph or kW equiv) would you have used?

Thanks, Roger

Roger, first photo the two round ends are 5/8" dia and about an inch long, bars are 1/4 x 3/4 and 1.625 long. They are the bearing caps for this engine

Disk is 3.125" dia and from 12mm thick hot rolled (black) plate, yes there is a small recess in the plate to take the end of the flange. This is it on a 6" rotary table

I only have a cheapish bullfinch torch and would say the burner I use is 5 to 6 kW, 4.5kg propane bottle