RE: POR's Metal Ready

[bearbvd@domain.elided (Greg Hermann)]

>Greg Hermann wrote:
>> >
>> >The best thing that the metal ready can do for you is to remove oils, etc
>> >that might be on the steel.  I've got some I'll be using to
>> ensure that the
>> >new steel panels I've got will be perfectly clean.
>>
>> Grease and oil and mill scale/varnish will shield the raw metal to some
>> degree from the metal prep (yep, it's phosphoric acid). If you want to get
>> steel chemically clean, first use a rather strong lye solution--this will
>> get off any grease, etc, , then use the phosphoric acid. Then--RINSE!!
>>
>Really?
>
>Do you think a solvent would be the best first step to address oils &
>greases?

It can be, but a hot lye solution works REALLY well! I would be inclined to
start out with a thorough session with a hotsy (steam cleaner) using a
fairly viscious soap, rather than a solvent, then wire brush a hot lye
solution on stubborn spots by hand, then go to warm phosphoric acid, using
a wire brush where necessary.

A waek solution of the phosphoric acid is the best way to neutralize the
lye before going to the stronger solution.

I've pickled entire heavy fuel oil piping systems for electric generating
stations using hot lye, followed by warm phorphoric acid!  Circulated them
with a pump for this. Gives pipes that are nothing but shiny bright steel
on the inside, and an absolute minimum of burner orifices that get plugged
by bits of grit that were trapped in the mill varnish on the inside of the
piping!

Greg