416 Ss

Walt2

Walt2

Joined
Mar 13, 2001
Messages
1,157
I have used a few of the 303SS cast guards that TKS sells. I had a problem with some having specks in the metal that showed up when polishing. I decided to change to 416SS and ordered a 1/4 x 1" bar from TKS. I found the same problem when I started to buff the guard. The metal is mill run, not precision ground. Anyone else seen this? Thanks
 
I've used 416SS for years and never had that happen.
Was it already HT'd when you got it...?
 
I do not know about the heat treat. Just looking at it I would say no and it doesn't seem to be harder than usual. This is just the flat bar stock that they sell.
 
Remember that both 303 and 416 are free machining grades.Higher amounts of sulfur are used which form manganese sulfides which act as chip breakers in machining. When you want a mirror polish sometimes these sulfides are visible as tiny specks !You might have gotten a batch with much higher sulfur. Using standard grades you would avoid it but 304 and 410 are more difficult to work.
 
mete said:
Remember that both 303 and 416 are free machining grades.Higher amounts of sulfur are used which form manganese sulfides which act as chip breakers in machining. When you want a mirror polish sometimes these sulfides are visible as tiny specks !You might have gotten a batch with much higher sulfur. Using standard grades you would avoid it but 304 and 410 are more difficult to work.
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Robert, I need to get some to start making guards. Which grade would you recommend? (Maybe you just did, but I've just had another 18-hr day.) Thanks.
- Mitch
 
Guards ? Wrought iron, damascus, stainless steel [303, 416, 304, 410 ] nickel silver, various types of brass or bronze depending somewhat on the color you want [260 {cartridge brass} ,silicon bronze etc] These metals also used for bolsters and end caps.
 
Well, I went back to trying to do something with this 416. I have ground the 1/4 in. down to a little less than 3/16 thick and everytime I try to finish it, I still see the specks. I took the piece to a friends house that has a microscope and looked at it. Turns out the specks that I am seeing are actually tiny, tiny craters. Looks like tiny bubbles have burst leaving the craters.
 
Mill run bar of any type requires a skinning pass with a coarse belt before attempting polishing. Pit marks are remains of the mill finish in most cases and will go away if the surface is re skinned in almost all cases.
 
I started with a 120 belt, then 220, 400, and 800. I went from 1/4" down to a little less than 3/16". Then buff, and where it shows up where I can see it is when I start buffing. Thanks for the replies, I guess I will have to try another piece or get some from a different supplier.
 
Walt, you probably buffed out or pulled out the sulfide inclusions and left craters. BTW if any of you have used graphitic tool steels such as O-6 .There the pockets of graphite ,used as chip breakers, will also be seen when highly polished....Comparing - 410 -.030 S max, 416 - .150 S Min [ no max listed and I don't know standard melting practices.]
 
mete said:
Walt, you probably buffed out or pulled out the sulfide inclusions and left craters. BTW if any of you have used graphitic tool steels such as O-6 .There the pockets of graphite ,used as chip breakers, will also be seen when highly polished....Comparing - 410 -.030 S max, 416 - .150 S Min [ no max listed and I don't know standard melting practices.]
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Yes, Professor, I got it. BUT... how in the heck do you "fix it"? :D
 
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