Hi Roland. A lally column is one of those steel poles commonly found in
garages and basements holding up various parts of the house. Sometimes
they're filled with concrete, but I have no idea if mine is. The method
you describe is pretty much what I had in mind. I think that if the pole
was "thin and lacy" it would probably have collapsed by now. It is
holding up a significant part of my house! There is enough rust that the
bottom of the pole must be thinner than it originally was. It is possible,
with significant effort and expense, to replace one of these columns. I'm
just trying to figure out how to reassure myself that if the rust is
eliminated, enough strength remains to be safe.
-Steve
At 05:25 PM 8/5/03 -0700, you wrote:
>Steve-
>
>I don't know what a lally column looks like but I know rust pretty
>well :-)
>
>You can wire brush or remove the rust with phosphoric acid (Naval
>Jelly is jelled phosphoric acid and it sticks to vertical surfaces
>pretty well without dripping onto the concrete floor and eating holes
>in it). Phosphoric acid is pretty benign with respect to human
>tissue, compared to muriatic acid for instance, and phosphoric acid
>does remove rust fairly quickly at 70 F. and above.
>
>When the rust is removed, you can see how much metal is left; it won't
>be any weaker than it already was. Coat the cleaned derusted metal
>with Corroless or other conversion coatings followed by a good metal
>enamel, and you're done. If the metal is thin and lacy, then you have
>to cut it out and replace with good metal, then protect and enamel.
>
>-Roland
/// unsubscribe/change address requests to majordomo@autox.team.net or try
/// http://www.team.net/mailman/listinfo
/// Archives at http://www.team.net/archive/shop-talk
|