Need metal rod help

[Bruce Wrenn]

Is this rod uses as a butcher's steel for their knives? If so, it needs to be harder than the knife itself.

[Wayne Lomman]

304 or 316 stainless steel is ideal for this. The bit of heat from cutting won't be a problem.

For general information, if you weld stainless steel it does discolour and will corrode. This is overcome by passivating (google it) the surface with nitric acid usually in a paste form for smaller jobs. This is how you are able to see large welded installations that are corrosion free. It doesn't just happen. Cheers

[Keith Outten]

Sorry Wayne but 304 or 316 stainless steel will not corrode or discolor from welding unless you exceed the welding technique specifications by using to much welding heat. I averaged over a thousand weld inspections per month for many years at North Anna Power Station and several other nuclear plants and I never saw a properly welded stainless weld corrode or discolor. I also worked in operating plants so I have seen these types of welds in service for decades.

Most likely bacteria will be a problem with this design, the metal rod is a very bad idea and tubing would not be preferred over solid rod.

[Bill Adamsen]

316 rod or tube. It is a bear to machine and does work harden, but likely not an issue in this application.

[David Winer]

I needed to cut a stainless steel rod for a cart axle, 3/4" diameter. Bought a low cost grinder (probably will find a use for it again someday) and a metal cutting blade. Beautiful; cut quickly and left a fairly neat surface that could be abraded to be more respectable.

[Wayne Lomman]

Keith, I stand corrected. The stainless welding I see is apparently performed by guys who have an unjustified opinion of their skills. We more routinely produce machined products using 431 and 630 for the maritime sector. Cheers

[Bill Adamsen]

The marine suitable stainless are (typically) those with a lot of nickel and the only type of stainless with a lot of nickel are those of austenitic structure. Austenitic steels also have chromium and in the case of the type 316, a lot of nickel and small amount of molybdenum. Type 316 and 316L (L for welded applications) have 10.5 and 10.8 percent nickel respectively. It is pretty available for rod and tube in the US. When buying screws from catalogs I have found they are rarely labelled for the type of stainless rather just "stainless." However, I just went to my favorite search engine and type "316 stainless screws" and was surprised by how easy it would be to focus on just those suppliers selling 316 stainless screws. Because of this issue in the past I stuck with silicon bronze. Maybe now that is less of a risk.

Stainless marine suitability, there are exceptions. Series 431 unlike most of the 400 series is martensitic, but is unusual in that it is considered suitable for marine even with its very low (~2% +/-) nickel. There are other specialty stainless series like "Carpenter 20" that might be suitable as well. My suspicion is you would not be able to readily source or buy them. Series 316 on the other hand is readily available from suppliers like Online Metals. I am shocked that when I buy from Online Metals the product is shipped from a nearby distribution center and arrives almost always the next day. I am sure other suppliers are good as well. Their 1018 cold rolled stock is gorgeous.

[Ole Anderson]

I would use 316 grade ss 3/8" solid rod. Cut with a 1/16" abrasive blade on a chop saw or an angle grinder. I used to buy mine from Copper and Brass sales in Detroit.