Greetings,
Thank you for your responses!

>that is the method I have used for years on our riveting cauldrons.  I
have to repeat the exercise periodically. We use our cauldrons to boil tea
water, cook stews, soups, etc.

Maeva
in Glymm Mere, An Tir
(Olympia, WA)

>you're filling the gaps between the plates, and  
the rivet holes, with naturally occurring adhesives/fillers, like  
fiber and starch granules from oats, cemented, caramelized sugars,  
both from the sugar you add and from the milk, and plasticized fats  
from the milk. 
Perhaps not nearly as new-looking and shiny as when you bought it,  
but still quite functional.

Adamantius

I appreciate both of your responses.  The reason I was wondering was because the fiber and starch granules that build up to fill in the gaps seems like it would soften and melt or wash away the next time you boiled water in the pot.  With cast iron (which I have several pieces of) when you "season" them the oil kind of soaks into the "pours" and oil doesn't disolve like starch will.  Maeva do you have that problem?  
May I also ask where you found your riveted pots?  Is there someone here in the US that sells them?  (I might be able to afford the shipping if I didn't have to have it shipped from Europe.)
One other question are they really heavy?  More heavy then a 2 quart Dutch Oven?  
Thanks again!
Fa'rissa