Spark testing: missing a piece to the puzzle.

I just read what feels like a million posts about spark testing and couldn't find this answer, so I thought I would break down and ask.

When I test something, can I use a cut off wheel, or do I really have to use a grinding wheel? In my head it shouldn't make a difference either way, but I have a few things that I thought for sure were stainless, but I can't get them to spark, even in the dark. I would really like to start the day at the scrap yard tomorrow and I have no desire to go to the store right now.

Originally Posted by holedigger

I just read what feels like a million posts about spark testing and couldn't find this answer, so I thought I would break down and ask.

When I test something, can I use a cut off wheel, or do I really have to use a grinding wheel? In my head it shouldn't make a difference either way, but I have a few things that I thought for sure were stainless, but I can't get them to spark, even in the dark. I would really like to start the day at the scrap yard tomorrow and I have no desire to go to the store right now.

It will spark like crazy with a cut off wheel.

If it looks like stainless, is non-magnetic, and is heavy like steel, I'd feel really comfortable throwing it in stainless. No need to really grind everything. Keep in mind, the magnetic part is really important. You can get low grade stainless that is magnetic and will still spark. Most yards won't buy magnetic steel as stainless.

If you have something that is not sparking with a grinder I'd be thinking copper, aluminum, or brass. What the metal came from should give you some kind of hints.

Originally Posted by jonnyjeb

Let me piggy back on this thread. Several bathroom fixtures I've come across are heavy like brass, but still retains the silver color when run through a grinder and no sparks whatsoever. The yard told me it was die cast aluminum. Thoughts?

Probably what we used to call pot metal;

http://en.wikipedia.org/wiki/Pot_metal