Recommended RPM for 5/16” solid carbide drill in 304 SS?

[erikmannie]

Why would you want to put a protective coating over polished stainless steel? First, it's polished stainless steel, it doesn't need protecting. Second, and perhaps important, is clear coatings filter light and alter the natural luster of the metal. It will cut the specular radiance and make the part look plastic. Something to think about while you're out earning bread for the week.

His neighbor has stainless fence brackets, & some of these have rusted a little bit after a few years.

How the Sea Breeze Can Affect Your Stainless Steel - Tampa Steel

In coastal areas, the chloride in sea spray, rain, and dry salt particles can contribute to the corrosion of stainless steel.

tampasteel.com

His house is very near to the SF Bay:



Trying to protect against this:



Apparently the chloride in the sea air will attack the material:

Will stainless steel 304 rust?

Will stainless steel 304 rust?

www.finishing.com

Quote from the link above:

“We find that regardless of grade (304/316) the tea staining or pitting will occur. This is mostly due to the brushed finish. Rolled or mirror finishes do not suffer from this.”

 

[erikmannie]

What is more, my brother works from his home office. His view from his office window? The inside (i.e. bracket side) of this fence!

I told him that I will supply the brackets with a beautiful finish, but that I don’t do paint so it was up to him to have the brackets finished, if he chooses to do so.

He doesn’t have time to mess with it, so I am to delegate this…to a body shop?

The reason that I don’t do paint is because I do it poorly. I don’t have an air compressor or a paint gun. When I used to have these, I rarely found the balance between haze, orange peel and drips on clear coat. I was actually bad at it! The few times that I did get it right, some dust, debris or bug would embed itself in the paint before it dried.

 

[wachuko]

 

[IamNotImportant]

Jurassic

 

[wachuko]

Jurassic

Well.... excellent representation of my paint attempts as well ... Maybe, in the far far future, they will create us again from the DNA extracted from something I painted...

 

[projectnut]

If you're looking for a material that won't rust use 316 stainless. We made food processing and packaging machines out of it for years with no problems. The processing machinery was washed down on a daily basis with caustic chemicals. There is no rust or corrosion after 40+ years of daily washdowns.

One thing to be careful of is to use dedicated wire brushes, buffing and deburring tools. Those used on other alloys can and will transfer material to the stainless. Then what appears to be the stainless rusting is actually the debris from the tooling that's been rubbed into the surface. Once imbedded in the stainless it's a real pain to remove.

 

[pontiac428]

In my climate, and salt atmosphere SS does dull, the ShineSeal (formerly ZoopSeal) I have been using SO FAR has not changed the surface it is protecting, and does not mask the metal shine. These pictures are of aluminum as machined no further polishing other than the aluminum polish applied with a cloth, and buffed. One is direct light the other is indirect lighting, and flash. The sealer is not visible, has not changed the shine, at least to me anyway.

Shine seal is like car polish. Not what I was thinking about when I said coatings; I as referring to coatings that build up a polymer layer- clear coat, polymer, paint, powder, varnish, stuff like that which is brushed, sprayed, electrostatically deposited, or dipped.

I wouldn't want my work to look like the grease-spatterd old China-made Wal-Mart patio barbecue either, man!

 

[DeadGuyAle]

One thing to be careful of is to use dedicated wire brushes, buffing and deburring tools. Those used on other alloys can and will transfer material to the stainless. Then what appears to be the stainless rusting is actually the debris from the tooling that's been rubbed into the surface. Once imbedded in the stainless it's a real pain to remove.

Those brackets look to be typical 304 stainless and maybe wire brushed with a non-stainless wheel.
316 stainless will not bleed or rust from my experience with a boat moored on saltwater.

 

[MrWhoopee]

One thing to be careful of is to use dedicated wire brushes, buffing and deburring tools. Those used on other alloys can and will transfer material to the stainless. Then what appears to be the stainless rusting is actually the debris from the tooling that's been rubbed into the surface. Once imbedded in the stainless it's a real pain to remove.

This is true, but once rusting has been initiated it will continue. It's not limited to the contamination.

Another vote for cobalt drill, preferably stub (screw machine) length for rigidity. Flood coolant if you have it, cutting oil or Tap Magic if you dont. Spot the hole, drop of oil, then LEAN on the drill. Resharpen as soon as the point starts to break down. Don't push a dull drill, work hardening happens quickly.

 

[Aukai]

The one component of the ShineSeal gets hard, the application pad gets stiff, and if you don't clean the threads where the cap screws on, the cap gets locked on. I'm not an expert, so these are my observations, and to remove it you use lacquer thinner. This is from the net...

How does it work? When Shineseal is applied, it impregnates into the pores of the metal and a chemical bonding takes place. Shineseal becomes one with the metal and seals off the breathing process which is the cause of OXIDATION AND DETERIORATION of the metal.