# What is 416ss like to machine?



## Investigator (Dec 4, 2019)

Got a project in mind.  I'm wondering what 416ss is like to machine.  I will mainly be milling deep pockets in round bar, the bar will be turned to correct OD in lathe prior to milling.  Just wondering what it might be like.  What I have found is 416 annealed.  Originally I had considered 7075 Al, but am thinking I need a bit more for longevity and corrosion protection.


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## Tozguy (Dec 4, 2019)

416ss is used for rifle barrels and machines fine, chamber reaming and threading are the usual operations.
I also profiled a couple of barrels in a long slow taper and it went great.


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## pontiac428 (Dec 4, 2019)

My experience with 416 is that it is a work hardening b!%ch of a material that cuts about like case hardened, but the results are really good.  I would suggest 316 instead, because it is easier to machine and has nickel in it, making it more corrosion resistant than the nickel-free 400 series.


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## ddickey (Dec 4, 2019)

416 is considered free machining. I've only used it a few times. Machines nice as far as I can remember.


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## benmychree (Dec 4, 2019)

I used 303 extensively in products that I made for the wine industry, it is considered as a "screw machine" stainless, does not work harden, has good corrosion resistance, but not recomended for welding, as it tends to undercut, but using a 308 filler it is OK for that as well.  It machines better than. CRS


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## seasicksteve (Dec 4, 2019)

Butta


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## MrWhoopee (Dec 5, 2019)

416 is very nice machining stuff. Maybe not as good as 303, but much better than 304 or 316. A friend recently brought me some old pump shaft to make into a driveline for the PTO on his service truck. I was afraid it would be 316. Much to my delight it was 416.


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## bakrch (Dec 5, 2019)

MrWhoopee said:


> 416 is very nice machining stuff. Maybe not as good as 303, but much better than 304 or 316. A friend recently brought me some old pump shaft to make into a driveline for the PTO on his service truck. I was afraid it would be 316. Much to my delight it was 416.



x2

I regularly work with 303, 304, 316, 410, 416, 420, 440C and 17-4PH. Industrial valve work, so it's these and a few others over and over and over and over again. 

303 and 416 are surely the most forgiving of this lot, but you will find that 416 isn't exactly "great" with corrosion resistance. 

Even when hardened to 40-ish HRC it's still pretty easy to machine.


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## Driveslayer45 (Dec 10, 2019)

how do you know what grade stainless you have... I often cut what i think is 304 but it came from a donut place. they were the metal conveyor rollers that moved the donuts along.  I think it machines fine, or more accurately i just don't know any better.  I have a PM727v and often cut it with 1/2 carbide end mills and more recently a fly cutter with a carbide lathe bit. I've made several things out of it and actually love machining it.


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## mmcmdl (Dec 10, 2019)

300 series if a magnet won't stick to it and it won't be L if it's on food grade equipment .


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## MrWhoopee (Dec 10, 2019)

Driveslayer45 said:


> actually love machining it.



That's not 304!


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## Jimsehr (Dec 10, 2019)

MrWhoopee said:


> That's not 304!


Look on google for   Machinability chart.   It will give you good idea of percent of machinability.


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## petertha (Dec 11, 2019)

Machinability Comparison Chart - provides percentage scale of machinability of various  metals indexed on 1212 carbon steel: carbon steels, alloy steels, stainless steels and super  alloys, tool steels, gray cast iron, nodular cast iron, alumunum all
					

Machinability Comparison Chart



					www.carbidedepot.com


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## Driveslayer45 (Dec 11, 2019)

magnets wont stick to it. so am i probably cutting 316?


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## MrWhoopee (Dec 11, 2019)

Driveslayer45 said:


> magnets wont stick to it. so am i probably cutting 316?



Something in the 3xx series. Assuming you're talking flat bar, 304 is most likely with 316 coming in a distant second depending on where it came from. 316 is the material of choice for better corrosion resistance, particularly acid exposure like tomato processing.


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## Driveslayer45 (Dec 11, 2019)

this is 2" round stock from a donut shop (dunkin or krispy cream)


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## MrWhoopee (Dec 11, 2019)

Driveslayer45 said:


> this is 2" round stock from a donut shop (dunkin or krispy cream)



Most likely 303 or 304. If you think it machines "fine", it's probably 303. 316 would be too expensive for donut shop applications where enhanced corrosion resistance is not required. It also does not machine nicely.


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## Driveslayer45 (Dec 11, 2019)

Thanks for the responses. Do understand I don't know what nice machining is, not really. I've milled cold rolled, and it's gummy, same with some random aluminum. This stuff is hard, but boy is it fun watching the chips fly. More than once I undercut a part because I was having so much fun cutting it .. ( ok, I know I sound like a real noob)


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## MrWhoopee (Dec 11, 2019)

Driveslayer45 said:


> Thanks for the responses. Do understand I don't know what nice machining is, not really. I've milled cold rolled, and it's gummy, same with some random aluminum. This stuff is hard, but boy is it fun watching the chips fly. More than once I undercut a part because I was having so much fun cutting it .. ( ok, I know I sound like a real noob)



Are you sure you're a noob? That's a nice looking part there.


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## Driveslayer45 (Dec 12, 2019)

Thanks, even a broken watch is right twice a day.  
Ok, so I have alot of hobby machine time, but I don't know, haven't tried to understand, why and how it works. I've just started trying to understand that. Up until now I've just been doing, and if something wasn't working I would do something else until I find a sweet spot, hence that part I pictured which has come out pretty well .. but I  still don't really understand why it came out as good as it did. It's a highway peg for my motorcycle, we'll see how close I can make the second one..


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## MrWhoopee (Dec 12, 2019)

Driveslayer45 said:


> Thanks, even a broken watch is right twice a day.



If you had worked for me, you would receive The Blind Pig Award. 
As my dad used to tell me, "Even a blind pig finds an acorn once in awhile".


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