I have a stainless steel deli slicer. Over the years one of the parts must have just barely warped enough to start rubbing against the blade. The solution seems easy enough, I’ll just take my angle grinder a shave a mm or so off of the part. What I want to know is if that’s going to cause any problems with the stainless steel? Mainly I’m concered that it could start rusting.
You don’t have to worry about the ground surfaces rusting with stainless steel. The corrosion resistance of stainless steel come from the alloying elements (mainly chromium if I remember my materials science correctly), so it has the same properties throughout. As far as grinding, you should be fine. Stainless is harder than mild steel, so it might take more effort than you expect.
My concern would be the finish on the part after you finished grinding it. A rough surface could harbor bacteria, and cause issues.
But ‘stainless’ steel can rust if it is pitted with inclusions that create corrosion cells. ‘Stainless’ is a misnomer, anyway; a term applied to various alloy steels with high chromium content (~10-26%) that display resistant to environmental corrosion. In the aerospace and marine equpiment industies these are referred to as corrosion resistant steels (CRES). I believe the types of stainless used in food service equipiment are generally AISI 304 and 316 steels.
That would be my concern as well. As homebrewers well know, it takes only a few scratches to harbor harmful colonies of bacteria.
Stranger
Also, you can get rust on the stainless parts if your grinding disc is contaminated with iron or carbon steel.
The grinding will embed the material that will rust into the stainless unless a new disc or a disc used only for stainless grinding is used. The actual stainless steel isn’t rusting, but the contamination is.
You can “pickle” the stainless with an acid to remove the rusting contamination, then “passivate” it to re-establish the corrosion resistant oxide layer.
Probably more than you wanted to know with regards to a simple mod on a deli slicer, but it is a way to introduce rusting.
Why grind when you can pound? I’d try taking the part off and pounding it with a ball peen hammer. I’d do that before I broke out the grinding wheel. It would solve the problem Rick eluded too as well.
300 series steels can be a bitch to grind (ask me how I know). Start with a brand new disk, grind a hunk of wax enough to coat the disk, then grind the steel. The wax will help prevent the disk from getting loaded up with steel, it will also keep the steel cool, which is important as 300 series steels work harden very easily. Start out with a coarse grained disk and gradually work up to the finest grained disk you can find.
I would suspect that after seven years, either the problem has been fixed or the slicer is now in the landfill.