Grades of stainless steel fasteners?

The operative words are "stain" and "less".

All "stainless" corrodes, it's just a matter of time.

All stainless requires the presence of oxygen to be effective.

I use strictly 316 for exterior marine applications since 304 and 18-8, basically the same, will pit rather quickly in the salt air environment found around a boat.

McMaster-Carr tends top be very pricey, but they usually have inventory.

If you are willing to purchase full boxes (100 pc) of a given size, try Jamestown Distributors, they are my main supplier and they are 3,000 miles away.

Don't know what you are doing, but have you thought of bronze?

HTH

It sounds like 18-8 is probably the common grade found in hardware stores.

McMaster-Carr isn't expensive compared to a local hardware store.

I am buying some socket cap screws. The black oxide ones will rust even in just a single light rainfall. I am building something that may occasionally get used in the rain.

Brian Elfert

Does anybody know a source for stainless fastners and hardware in really small sizes? Places like Jamestown and McMaster only go down to about #6 or maybe #4 for some stuff. I need smaller. Like 2-56 or even smaller than that.

I've got a radio controlled sailboat, which I sail in salt water. Most of the hardware on it came from a hobby shop, but they really cater to planes and cars so nothing is stainless. Needless to say, most of my hardware is quickly rusting.

We use the 18-8 machine screws and socket cap screws, mostly from McMaster. They are used in tooling that is subjected to steam, water (pH 6.4), air, vacuum cycles every 30 to 60 seconds for 24 hours a day, sometimes for months at a time. They hold up well. Never found a reason to use a more expensive item. Ed

I'm certainly not planning on buying the 316 stainless fasteners. I was just trying to determine if the 18-8 or the 304 stuff is the same as the stuff sold at the local hardware store.

It appears the 18-8 is the same grade as the normal hardware store stuff.

Brian Elfert

My local hardware store has a bin of small stainless bolts. Not sure if they go down to #2 though.

Brian Elfert

the info!

try contacting the people at micro-mark -- they specialize in miniature stuff

also try smallparts.com

Roy Smith bellowed forth with this wisdom for all to hear:

This should help from Atlas Steels:

Chemical Formula Fe,

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to be helpful.