I know this is an old thread but I felt i had to address the idea of using Evaporust on chains. I rebuild bikes for a hobby, like most here, I sell sell or donate the ones I don't keep. On a few occasions, I used Evaporust on chains. What I got was a beautiful chain, like new. The first one, I put on the bike and rode 3 blocks to the supermarket, the chain snapped before I got there. A link had broken in half. Ok, maybe the chain was weak. Next one went on a bike I sold, next day the buyer came back with a broken link in the chain. i had one more which i put on my bike to test, sure enough, the chain broke. 100% failure record, This stuff somehow weakens the type of metal used in chains. I love it for so many other things, and if bikes were for display only, it makes a rusty chain look so nice. Anyway, hope I helped someone avoid a chain failure
Due to the way the chelation process works, selectively making it more attractive for iron oxide to enter solution, but having no effect on base metal, I'm skeptical of the claim that Evaporust weakened the chains. Chains that were rusted badly enough to require de-rusting may well have had damage before being de-rusted.
One experiment to prove your claim would first pull test rusty chain segments BEFORE de-rusting, then expose to Evaporust, then pull test again with resultant fracture at the same, or lower levels of stress.
There is one case where Evaporust apparently could cause weakening of base metal. If a surface is not entirely submerged, the line where liquid surface and air meet, can be damaged. The base metal may be rusted, and etched in a continuous cycle at this interface, causing a score line or notch to be etched into the metal. Notches or even scratches in metal surfaces have the effect of multiplying stress in the surface. These sources talk about this effect in more detail:
A common goal in restoring an antique hand plane is dealing with the, sometimes, copious amount of rust on the cast iron. There are an unlimited number of methods for addressing the rust, from leaving it alone, to removi...
Hi all, Have been using Evaporust during the restoration I'm working on and noticed that it seems to effect "cast iron", if you leave the part soaking in for at least 2 days. The rust comes off as advertised, but it seems that it takes pristine iron down with it. Surfaces that were rust free...
Personally, I use phosphoric acid for the majority of my de-rusting chores, including on chains because:
- Unlike most available acids, phosphoric does not appreciably attack base metal, only rust.
- Unlike most available acids, phosphoric converts iron oxide to iron phosphate, which is resistant to re-rusting. This is a huge advantage, in my opinion, an advantage that phosphoric acid has even over chelating de-rusting solutions like Evaporust, which leave the surface vulnerable.