304 316 Stainless Steel Metal (inexpensive detection liquid) Test Kit : Climbing bolts & hardware

I order some of my climbing hardware and other metal goods directly from manufacturers. And sometimes I get stuff from friends. I’ll demonstrate this inexpensive liquid drop detection test kit for different grades of stainless steel. The Mn blue liquid will change color on 200/300 series of stainless steel based off of ≤2% Manganese錳 content.

The other two require a 9V battery. The N8 bottle tests for the ≥8% Nickel鎳 found in 304. The M2 bottle tests for the ≥2% of Molybdenum鉬 in 316.

I’ve demonstrated these 3 test kits on 3 different hangers: Petzl Couer Steel, SS304, & SS316.

Another quick method is a magnet test, to see if the stainless steel is ferritic or martensitic (e.g. 400 series, or steel) and will stick to the magnet; or if it's austenitic (like 304 and 316) and hardly attracts. 304 and 316 are non-ferromagnetic. Sometimes you’ll notice 304 may seem to be more attractive than 316. But it isn't always reliable nor tells you the content of the steel. Like when comparing the 304 ring to the 316 chain, it felt the same, nor does a magnet test really tell you what metals are present in the alloy…The 316 test did however. The 316 test drop stays red, whereas the 304 eventually completely fades away.

So, where to buy? Good question. I’ve gotten mine off Shoppe and Taobao for about NT$200-300 (about $6-10 USD). The only test liquid kits I’ve seen on AliExpress are the more commonly found “304 stainless steel detection liquid identification liquid manganese content test fluid”, and no 316 ones. Email some sellers I suppose? Or if enough interest is found in this I suppose I could help some developers out in acquiring some in a batch order.