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UTV's Off Road ( RZR, YXZ, Mini Buggy, Carts,etc.) => UTV General Discussion => Topic started by: Stomper on November 25, 2009, 08:05:26 AM
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I need to machine some stainless steel. Would HSS or carbide tooling be good. Also what speeds should I run.
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Mill or lathe? HSS is a poor choice IMO.
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SHARP! HSS works good at about 40 SFM with coolant and or oil.
Carbide tolling you can push it up to 300 SFM.
What grade, size and type of cut. ll get you pointed in the right direction! ;D
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That he will!
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SHARP! HSS works good at about 40 SFM with coolant and or oil.
Carbide tolling you can push it up to 300 SFM.
What grade, size and type of cut. ll get you pointed in the right direction! ;D
Its just some small stuff and not very much. Its 316L. And it's on a lathe. I won't be using the auto feed as it's a small job. I don't have a coolant pump on my lathe. SFM ???. I was thinking RPM :-[. As you can tell I'm not much of a machinist. Just learning
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DOug will fill ya in I'm sure but SFM is calculated by taking the circumference X rpm. Example is 1" round has 3.1416" circumference X say 300 rpm on lathe the formula is 3.1416X300 divided by 12"(to convert to feet) = 78.54 SFM
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So SFM is: circumfrence X rpm divided by 12" = speed in feet per minuite ???. BTW nice simple example. Thats what I need ::)
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yup
So SFM is: circumfrence X rpm divided by 12" = speed in surface feet per minuite ???. BTW nice simple example. Thats what I need ::)
yup
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We refer to SFM alot as "Surface Speed" here at the shop as many do.
Here are simple speeds to keep in mind for material and tool types...
Coated (TIN) carbide inserts...
-Steel = 500 - 750
-Aluminum = 750 - 1200
-Stainless = 250 -350
Non Coated Carbide tooling...
-Cut above speeds in 1/2.
HSS Tooling...
-Stainless = 40
-Steels really depend on grade and hardness and wether it is leaded, but a good mild steel you can run up to 200.
Here is another tidbit of info I can offer... When running HSS there really is no limit to how slow of RPM you can run. When cutting with Carbide that rule does change on the tool chip geometry, material, and depth of cut as Carbide will chip or break easier that HSS. You will Just burn up HSS if you go too fast.
OK, Now to find the RPM.
SFM X 3.82 / diameter of cut = RPM
so on a 1" diameter cut of stainless (304 - 316) here is the "fill in" below.
300 SFM X 3.82 divided by 1" = 1146 RPM
noncoated is 1/2 of that so nowitsabout 575 RPM
HSS I say about 40 SFM so here is that break down...
40 X 3.82 divided by 1" = aprox 150 RPM
And so on and so on.
The material your cutting, the L stands for leaded stock as you may know. This is good for you as it will be easier on your tooling.
Hope that helps!
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You just got stickied! ;D ;D Good info right there!
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You just got stickied!
My GF hates that...
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I hate cutting stainless !!
I hate welding stainless !!
I hate shearing stainless !!
I hate buffing stainless !!
If it has to be made from stainless, double the labour costs!!
Just my opinion !! ;D
Correct me if I'm wrong, but I thought that the"L" meant it was low carbon ! ???
scroll down half way on this link
http://www.lenntech.com/stainless-steel-316l.htm (http://www.lenntech.com/stainless-steel-316l.htm)
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My GF hates that...
Yeah!! I know she does LMAO
Sorry !! I couldn't resist !! ;D
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My GF hates that...
I thought it was slimed she hated. ;) ;D ;D
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I thought it was slimed she hated. ;) ;D ;D
First she gets slimed, then she gets stickied !! ;)
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......... LMAO
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I'm not worried, she doesn't like old fookers. Ya smell funny.
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I know it to be leaded. Stainless has no carbon as the carbon would be magnetic, right?. Carbon is present in some magnetic stainless steels like 400 series stainless and 17-4 where it can be hardened.
Oh and another note on stainless machining... DO NOT try to cut it too fast as it may work harden and you will piss trying to punch through it!
My wife loves the stickey!
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I'd have to look it up, but I don't believe carbon is magnetic. Iron is though. I also believe that stainless does have carbon in it.
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Actually I believe you are correct as carbide (carbon) inserts are not very magnetic although they do draw slightly.
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#9 The L stands for low carbon.
http://www.ssina.com/faq/index.html (http://www.ssina.com/faq/index.html)
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Thanks, I learned somthing new myself!
What I was refereing to, because I see it more, is materials like12L14 (mild steel) where the L is within the grade number and does mean leaded stock. I have Stainless with the L after it and always avoided using it in welding applications. Now I know different. It is easier to cut though which was my inital statment.
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Here's another tip that I use !!
To tell the difference between 304 stainless and 316, I use a rare earth magnet (those realy strong ones ).
304 will have no attraction, but the 316 will attract the magnet slightly.
Here's another confusing thing about stainless.
I use 304 "J" bends for doing exhaust. A rare earth magnet won't stick to the straight part, but will where the tubing has been bent. I still have not figured out why this happens. Would love the answer to this !!
Here's the chemistry makeup of 316 stainless;
Chemistry % by Weight
Fe 62.045-72%
Cr 16-18%
Ni 10-14%
Mo 2-3%
Mn 2%
N 0.1%
S 0.03%
C 0.03%
Si 0.75%
P 0.045%
As you can see, there's no lead (pb) present.
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Yeah I'm still trying to figure out where the lead is that doug talks about. Maybe on the surface for some purpose during rolling it to thickness? ?? ?Lube maybe? Hell I don't know. I've never heard of it IN SS.
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The lead I know to be present is certianly in steels. We use 12L14 and 41L40 for specific jobs and the presence of the lead is to increase machining speeds for high production. the material is slightly more expensive. It is way easier to machine than non leaded.
Since this thread, I thought tha 316L, The L stoof or ead as well. I guess I just thought the same for streel was the same for stainless. Obviously not. If anyone wants me to send a small sample piece of 12L14 for the fun of seeing how easy to machine it is. Let me know.
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I've got a theory there Hemi. This is just shooting from the hip, but Fe is iron which is magnetic and makes up the largest part of 304. The chromium and nickle "shield" the magnetic properties in the straight section, but in the curve the material is stretched. The chromium and nickle is spread thinner allowing more of the iron's magnetic properties to surface. I'm no expert though, I just watched somebody play one on an infomercial once. LMAO
EDIT My bad, I see that was the chemistry for 316. Oh well, Imma gonna stick to my theory anyway.
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The lead I know to be present is certainly in steels. We use 12L14 and 41L40 for specific jobs and the presence of the lead is to increase machining speeds for high production. the material is slightly more expensive. It is way easier to machine than non leaded.
IIRC the lead is for lubrication and also aides in chip separation.
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Here's another tip that I use !!
To tell the difference between 304 stainless and 316, I use a rare earth magnet (those realy strong ones ).
304 will have no attraction, but the 316 will attract the magnet slightly.
Here's another confusing thing about stainless.
I use 304 "J" bends for doing exhaust. A rare earth magnet won't stick to the straight part, but will where the tubing has been bent. I still have not figured out why this happens. Would love the answer to this !!
Here's the chemistry makeup of 316 stainless;
Chemistry % by Weight
Fe 62.045-72%
Cr 16-18%
Ni 10-14%
Mo 2-3%
Mn 2%
N 0.1%
S 0.03%
C 0.03%
Si 0.75%
P 0.045%
As you can see, there's no lead (pb) present.
As for why the Stainless is magnetic on the bends? The answer is that it depends. Your 316 SS is 'austenitic' and has a face center cubic crystal structure. It is the nickel which modifies the physical structure of the steel and makes it non-magnetic.
Now when you make a tight bend in your material you're going through the materials elastic modulus and into it's deformation modulus. By doing so you have pulled apart many of the bonds and there for have physical changed the crystal structure just enough to make it resemble a more 'martensitic' or body centered tetragonal crystal structure state. So depending on how much and how tight your bend is will effect it's magnetic properties.
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N0w that's interesting. Thanks for the info.
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Too many big words for me! drowning
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DId you guys realize that at approx 1700*F mild or alloy steel is not magnetic?
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No I didnt, Hmm
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DId you guys realize that at approx 1700*F mild or alloy steel is not magnetic?
Were you taking it out of your oven with a magnet and dropped it on your toe?
Something tells me there is a story behind this random fact. ;D
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Yep,there is. When steel hits non magnetic it is capable of absorbing carbon. Case hardening. It is also the point of thru hardening higher carbon content steels.
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DId you guys realize that at approx 1700*F mild or alloy steel is not magnetic?
Yes, that's when it's crystal structure changes
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That too.
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316 l or sometimes 316 lo means low oxygen and is more corrosion resistant than 316
most 316 castings are magnetic when they come out of the sand because they cooled to slowly , then you heat treat them , non magnetic again
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That ,I did not know. Thanks for the info.
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Holy necrophilia bump Batman
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Thanks, I learned somthing new myself!
What I was refereing to, because I see it more, is materials like12L14 (mild steel) where the L is within the grade number and does mean leaded stock. I have Stainless with the L after it and always avoided using it in welding applications. Now I know different. It is easier to cut though which was my inital statment.
316L or 316LO means low oxegen and slitely is more corrosion restant than plan 316 as it requires a lower amount of oxygen to mantaine its resitance