Just to add to the Library, Using a lakeshore carbide 1/2" 6 flute 7800012 on my series 3. Cutting 316L stainless, using a setscrew TTS holder, full flood. I burned up a couple of endmills trying a deeper cut approach and was getting a lot of chatter especially in the X direction. This made me believe that the rigidity of machine was coming into play so I started backing off on the depth. I found a working sweet spot at 2000rpm, 15IMP, 0.1 depth of cut, 0.1 stepover. The finish isn't bad on the side cut and the tool survived! I think I can get it better and will have to do some more test cuts but for whoever wants to go with a 1/2" that should get you going. Thanks for all of the great information!!
Milling 304 is easy, just sure to make some steps: 1- Use a lot of coolant. 2- low feed and low RPM 3- Put an Madre de Guadalupe image inside the machine table to help with the vibration...
Another tip with the coolant is to raise your concentration. We use qualichem 250C (I think that's what you use) and if we are running a bigger job in 304 I will raise the concentration to 12-15% I find that makes the biggest difference of all.
I appreciated this video! I'm working with a little $500 desktop CNC so no way any of these tools or materials are making their way into my workflow, but this did give me some useful insight into how I should be thinking about engraving softer steel. Great video and really appreciated, thanks.
My own personal experience, but Instead of the Dijet cutter use a lakeshore 5 flute with a .010" ADOC. Cheaper cutter and leaves a lower RA finish because the bottom is flat. In my 770 on low belt I use a 3/8" diameter with a .3" step over, 220 SFM at .009 IPT. In my VF2 I run a 1/2" diameter with a .45" stepover at 300 sfm and .015 IPT. About %98 of my work is 304 stainless and my parts must have a 8-12 RA finish on all faces, I've found this to be the fastest, most economical way to face any surfaces. I get about 16 hours of cutting life on the 770 and have hit 40 with the VF2, flood coolant both. Great for pocketing quickly also, use the highfeed aproach just with a standard endmill. I do own a Dijet highfeed cutter and use it in the 770 frequently for punch/die jobs I see frequently (prehard D2 steel 55Rc) and have tried it on stainless steel. Simply put, 5 flutes move faster with the right tool paths. other general starting tips from someone who has 15 years with primarily stainless: 304 machine start at 220 SFM for Altin coated 316 at 210 Sfm for AlTin 410 at 175 SFM for Altin Cutting depths depend on type of cut and machine rigidity. Keep the tool moving, there is no minimum cut depth, just don't let it rub. Don't use wiper inserts most all raw stainless has a hard abrasive crust or shell that tends to resist cutting, once this is gone it cuts like butter Great vids John! I've followed your channel since your first 1100, you do a great job of sharing valuable information and inspiring others to join in on a once dying industry!
@ 7:00 : Ra doesn't tell you a lot about anything really, it's a hold over from a time that's all we had to work with. Rz (difference between 5 highest peaks and 5 lowest valleys within sample) gives you a lot more information about the surface in general. but that's by no means the end of it. Rmr (how much material do you see at a certain depth from the top peak in a sample, in other words; does a part look like mesas or like mountains) is very important for hydraulics for instance, where you'd want valleys for lubrication but not peaks that cut your seals to shreds. you have quite a nice tester (although a bit classic, but with a new probe it looks like). as far as i know it does Ra, Rq, Rz and Rmax. Rq is the RMS of the given surface, already a way better indicator of general smoothness than Ra which is just the arithmetical average (in Ra a perfect sine wave surface would come out to 0). Rz says a lot about how "peaky" the surface is. Rmax just gives the biggest deviation from the mean, so is prone to plane bad luck. I'm what one would call "a difficult customer" when it comes to surface finishes. i've made a lot of tiny, thin-walled, difficult material hydraulic and pneumatic stuff that has to function for a long time and be absolutely reliable. i tend to have to train machinist in what it is i want in this regard, since most of them just get asked an Ra and that's the end of it. i usually have an Ra (because it's mandatory when calling a roughness mark), an Rz and an Rz dependant Rmr) when specifying an important surface condition. i've had break machinists hart when they show me a part on which they got an Ra that was a 10th of what was asked, only for me to tell them that now the Rmr was too high, the surface too smooth for me to work with (yes, too smooth is a thing in hydraulics). surface finishes is a bit of a niche field, but well worth getting into a bit as a machinist/shop-owner, specifically because a lot of your clients don't know enough about it (just like most, including me sometimes, don't know what makes a part easier to machine)
I really like the look of that Lakeshore engraving tool. Up till now I have been using a 2FL 1/16 die sinking ball mill. It has a cut length of only a little longer than the ball radius. Say about .080". These work exceptionally good and holdup good. I have used it in 304, 316,17-4, Nitronic 50 & 60 and Inconel. Between .005-.01 depth of cut 5 Ipm feed and 2 Ipm plunge at 6000 RPM on the Mit's (Its max speed) and 10,000 on the Mazak. But It costs almost twice as much for a single ended tool. I think I will give the Lakeshore a try. Can you get the Lakeshore tool with a coating? I couldn't tell from the link you gave on the tool.
John, Ever try oil instead of soluble in your spray mist for engraving? Makes a huge difference for me. Great video again, as usual. Alway informative.
I have had success engraving 304/316 with a small ball endmill (3/64" or 1/16") and going about .003"-.005" deep. I like that idea of using a carbide centerdrill.
The first Full time CNC setup programming job I had was in 1988. We made aluminum microwave housings. Hand G code. Then the boss took in a 304SS microwave part. We had used form taps on all previous parts. I questioned it and said maybe we should use cut taps. Nope - so I setup to use form tap drill size - we tapped off line. Broke taps after the lot was done, had to make them all again.
The only stainless I work with is is 303 and 304. We use a 2.5" face mill with the SEKT style inserts for most facing operations. 850 RPM and .004 chip load works great without coolant on deeper cuts. But, if I'm taking a .03 depth or less cut, I use coolant otherwise there's a tendency of chips dragging and sticking on the backswing. And yeah, like you said, burrs are a pain on 304 especially with a dull cutting tool.
There’s also a vast cutting difference between 304 and 304L. That little bit of extra carbon in the 304 makes a huge difference in getting a clean cut chip versus getting mushed over edge in 304L
Depending on how much material is coming off a great strategy is using an opti I use master cam witch it is called dynamic to cut the balk of either the outside of the part or taking the back off. I use the widia 3/8 varimill with a .03 rad. I then take the same cutter in half inch and cut .01 off to finish it (top). If doing this on bigger plates you normally can not go to size. It can warp and bow up to .01 I do plates that are 12 mm thick by 7 by 14 and have to be with in .003 and it must be flat and parallel and doing that I can nail that every time. When roughing I take 5-8% of the cutter going 200 ipm @ 4500-5000 rpm and to finish I typically go 175 sfm with a chip load per tooth of .0011 and that will put me around 1500 and 15. Now normally can go up to 2850 and 22ipm when hitting the top of the pcs with a half inch end mill. That is done in any of our vf2's or our vf3!!! :)
we mill 304 at a much lower sfm, around 120. its really dependent on spindle rigidity sincle 304 requires a lot of backpressure to cut. its tough not hard so it likes to peel and not be shaved away. its like peeling an orange, unless you have supermans finger of steel, you need to slowly pierce the top layer and once the cut is started the rest will follow. too fast of a piercing action (sfm) paired with too light of a cut leads to extra wear and more burrs and less material removal. at higher sfm the spindle doesnt have enough time to return to center and it bumps&rides along the surface instead of having the opportunity to pierce the orange and peel the rest of the chip way
I found that to as well, that basically Fusion 360 treats an Engraver as a Chamfer Mill. I may have discovered that in their Wiki. The benefit though, is that on a Chamfer Tool you can set all the parameters (like point angle, etc), to match the tool that you have.
Love 303, like 316, kinda hate 304. BUT I think that 304 when polished has a much better feel than any other material. I've recut all the balls for my machine handles in 304 and it just feels better. I don't know how to explain it. I have made a series of balls, 1 inch diameter in a myriad of different materials to test this and it's unanimous. A ball of polished aluminum or brass feels different than a ball of polished 304. I assume it's because the stainless holds heat better so your hand warms up the part instantly, where aluminum and other materials take longer to warm up by hand and feel cold. 304 takes a brilliant polish too. It's gummy and crappy to machine though.
As always great informative video, been watching since the beginning days in NY, I learn something in every video. I have had to do a lot of engraving in 304 and 316, I have tried a lot of tools and by far best tool Harvey 939716-C3 1/4" 90 degree .015 tip. lots of coolant and ramp in no plunge. I have cut .015 to .020 deep to fill with powder coat and the tool lasts a long time.
Thin cuts on steel with carbide inserts are incorrect working conditions. You are forging, and hardening the surface instead of getting under it with a nice cut. Thing is with 304, it doesn't like heat, the surface melts and sticks to the cutting edge of the cutter, by doing that, it "chockes" the cutter, increase load and eventually breaks the cutter. Just avoid high rpm's ,full diameter penetration and full diameter plunges. Also use sharp edge cutters.
Fischer977 That’s not an issue when using high feed milling inserts which are specifically designed for shallow depths of cuts. Most high feed inserts max out at around a .025-.030 DOC. A .005-.010 is perfectly acceptable
I find it funny how I see multiple American jobshops go around stainless steels and even harder materials saying they're hard to machine. I'm a schooled machinist and I haven't had any issues with it at all. Carbide is the only way to go for stainless and up, preferred with a coating like TiCN. And cooling, flood that endmill with coolant, it's a CNC not a manual mill
Agree. Work with 304 and 316 on a more than regular basis - lots of coolant on carbide endmills. Carbide inserts on the other hand when face-milling; I usually run with air instead of coolant, as the thermal shock will crack the inserts faster instead of letting them transfer the heat. At least from my experience after years of trial and error. The main issue I have with stainless is the tension that builds in the material once you machine it - especially on long/plate/thin parts :P
@@PatrickJoergensen the tension is in all materials but yea stainless really is a bitch, I always try to work towards the center in stainless. Prefer running a program a few minutes longer then having to make 10% extra for the warp that's going to be introduced
@@xenonram haha well you call it European bullshit comments, I call it America needing to reinvent a wheel because it's America. It's stainless not some rusty tin can that you could machine with your shoes. Get some decent carbide tools and flood them cause it's gonna get hot
Fusion 360 doesn't let you program a trace with a centre drill? I use HSM works (which is the same thing) and that lets you use a spot drill for tracing.
Hello John How are you? I need your help John please. I have a problem with my fusion 360 I cannot see tool display when I want a new tool selection ? Have a nice day
I feel its the use of "pro tip" without including credit to the pro in the same statement that turns some people off. This "pro youtuber" has just busted a bunch of tools and wants to share what he the other machinists that work for the company ended up doing, would probably go over better. Sorry but I was actually busy with work today! not at work, I don't work for someone else haha.
Coolant, that is your surprise? Like its unexpected and counter intuitive? Really? You mean coolant on a metal that builds up localised hotspots did something? Come on dude.... that was in the vid just to increase viewer retention. It was a cheap trick to help your numbers.
Just to add to the Library, Using a lakeshore carbide 1/2" 6 flute 7800012 on my series 3. Cutting 316L stainless, using a setscrew TTS holder, full flood. I burned up a couple of endmills trying a deeper cut approach and was getting a lot of chatter especially in the X direction. This made me believe that the rigidity of machine was coming into play so I started backing off on the depth. I found a working sweet spot at 2000rpm, 15IMP, 0.1 depth of cut, 0.1 stepover. The finish isn't bad on the side cut and the tool survived! I think I can get it better and will have to do some more test cuts but for whoever wants to go with a 1/2" that should get you going.
Thanks for all of the great information!!
A center drill for engraving. It never crossed my mind. Thanks for the tip for whenever I'm in a pinch and don't have the proper tooling.
Milling 304 is easy, just sure to make some steps:
1- Use a lot of coolant.
2- low feed and low RPM
3- Put an Madre de Guadalupe image inside the machine table to help with the vibration...
Another tip with the coolant is to raise your concentration. We use qualichem 250C (I think that's what you use) and if we are running a bigger job in 304 I will raise the concentration to 12-15% I find that makes the biggest difference of all.
Thank you so much! I am just about to do a job with 304 for the first time. Great timing!
I appreciated this video! I'm working with a little $500 desktop CNC so no way any of these tools or materials are making their way into my workflow, but this did give me some useful insight into how I should be thinking about engraving softer steel. Great video and really appreciated, thanks.
My own personal experience, but Instead of the Dijet cutter use a lakeshore 5 flute with a .010" ADOC. Cheaper cutter and leaves a lower RA finish because the bottom is flat. In my 770 on low belt I use a 3/8" diameter with a .3" step over, 220 SFM at .009 IPT. In my VF2 I run a 1/2" diameter with a .45" stepover at 300 sfm and .015 IPT. About %98 of my work is 304 stainless and my parts must have a 8-12 RA finish on all faces, I've found this to be the fastest, most economical way to face any surfaces. I get about 16 hours of cutting life on the 770 and have hit 40 with the VF2, flood coolant both. Great for pocketing quickly also, use the highfeed aproach just with a standard endmill. I do own a Dijet highfeed cutter and use it in the 770 frequently for punch/die jobs I see frequently (prehard D2 steel 55Rc) and have tried it on stainless steel. Simply put, 5 flutes move faster with the right tool paths.
other general starting tips from someone who has 15 years with primarily stainless:
304 machine start at 220 SFM for Altin coated
316 at 210 Sfm for AlTin
410 at 175 SFM for Altin
Cutting depths depend on type of cut and machine rigidity.
Keep the tool moving, there is no minimum cut depth, just don't let it rub.
Don't use wiper inserts
most all raw stainless has a hard abrasive crust or shell that tends to resist cutting, once this is gone it cuts like butter
Great vids John! I've followed your channel since your first 1100, you do a great job of sharing valuable information and inspiring others to join in on a once dying industry!
Thanks! This is excellent information!
As a lathe guy, I find all stainless a joy to turn. But I also don't have to mill it ^_^
@ 7:00 : Ra doesn't tell you a lot about anything really, it's a hold over from a time that's all we had to work with. Rz (difference between 5 highest peaks and 5 lowest valleys within sample) gives you a lot more information about the surface in general. but that's by no means the end of it. Rmr (how much material do you see at a certain depth from the top peak in a sample, in other words; does a part look like mesas or like mountains) is very important for hydraulics for instance, where you'd want valleys for lubrication but not peaks that cut your seals to shreds. you have quite a nice tester (although a bit classic, but with a new probe it looks like). as far as i know it does Ra, Rq, Rz and Rmax. Rq is the RMS of the given surface, already a way better indicator of general smoothness than Ra which is just the arithmetical average (in Ra a perfect sine wave surface would come out to 0). Rz says a lot about how "peaky" the surface is. Rmax just gives the biggest deviation from the mean, so is prone to plane bad luck.
I'm what one would call "a difficult customer" when it comes to surface finishes. i've made a lot of tiny, thin-walled, difficult material hydraulic and pneumatic stuff that has to function for a long time and be absolutely reliable. i tend to have to train machinist in what it is i want in this regard, since most of them just get asked an Ra and that's the end of it. i usually have an Ra (because it's mandatory when calling a roughness mark), an Rz and an Rz dependant Rmr) when specifying an important surface condition. i've had break machinists hart when they show me a part on which they got an Ra that was a 10th of what was asked, only for me to tell them that now the Rmr was too high, the surface too smooth for me to work with (yes, too smooth is a thing in hydraulics). surface finishes is a bit of a niche field, but well worth getting into a bit as a machinist/shop-owner, specifically because a lot of your clients don't know enough about it (just like most, including me sometimes, don't know what makes a part easier to machine)
I really like the look of that Lakeshore engraving tool. Up till now I have been using a 2FL 1/16 die sinking ball mill. It has a cut length of only a little longer than the ball radius. Say about .080". These work exceptionally good and holdup good. I have used it in 304, 316,17-4, Nitronic 50 & 60 and Inconel. Between .005-.01 depth of cut 5 Ipm feed and 2 Ipm plunge at 6000 RPM on the Mit's (Its max speed) and 10,000 on the Mazak. But It costs almost twice as much for a single ended tool. I think I will give the Lakeshore a try. Can you get the Lakeshore tool with a coating? I couldn't tell from the link you gave on the tool.
I ended up using a 1mm mitsubishi 2 flute ball for hard materials, that is my go to engraver on low rpm machines
Tough stuff. Working on 304 and 316 sheet mental the bend pressure difference for MS and SS is massive. Thanks for the great video.
Who else loves the look and feel of raw 304 stock?
John, Ever try oil instead of soluble in your spray mist for engraving? Makes a huge difference for me. Great video again, as usual. Alway informative.
Thank you for the matter of fact education. Brilliant as usual.
my job works with 304 exclusively. fun when it flexes
I have had success engraving 304/316 with a small ball endmill (3/64" or 1/16") and going about .003"-.005" deep. I like that idea of using a carbide centerdrill.
Nice John, great to see some 304 what neat work.
Lance & Patrick.
The first Full time CNC setup programming job I had was in 1988. We made aluminum microwave housings. Hand G code. Then the boss took in a 304SS microwave part. We had used form taps on all previous parts. I questioned it and said maybe we should use cut taps. Nope - so I setup to use form tap drill size - we tapped off line. Broke taps after the lot was done, had to make them all again.
The only stainless I work with is is 303 and 304. We use a 2.5" face mill with the SEKT style inserts for most facing operations. 850 RPM and .004 chip load works great without coolant on deeper cuts. But, if I'm taking a .03 depth or less cut, I use coolant otherwise there's a tendency of chips dragging and sticking on the backswing. And yeah, like you said, burrs are a pain on 304 especially with a dull cutting tool.
There’s also a vast cutting difference between 304 and 304L.
That little bit of extra carbon in the 304 makes a huge difference in getting a clean cut chip versus getting mushed over edge in 304L
Depending on how much material is coming off a great strategy is using an opti I use master cam witch it is called dynamic to cut the balk of either the outside of the part or taking the back off. I use the widia 3/8 varimill with a .03 rad. I then take the same cutter in half inch and cut .01 off to finish it (top). If doing this on bigger plates you normally can not go to size. It can warp and bow up to .01 I do plates that are 12 mm thick by 7 by 14 and have to be with in .003 and it must be flat and parallel and doing that I can nail that every time. When roughing I take 5-8% of the cutter going 200 ipm @ 4500-5000 rpm and to finish I typically go 175 sfm with a chip load per tooth of .0011 and that will put me around 1500 and 15. Now normally can go up to 2850 and 22ipm when hitting the top of the pcs with a half inch end mill. That is done in any of our vf2's or our vf3!!! :)
we mill 304 at a much lower sfm, around 120. its really dependent on spindle rigidity sincle 304 requires a lot of backpressure to cut. its tough not hard so it likes to peel and not be shaved away. its like peeling an orange, unless you have supermans finger of steel, you need to slowly pierce the top layer and once the cut is started the rest will follow. too fast of a piercing action (sfm) paired with too light of a cut leads to extra wear and more burrs and less material removal. at higher sfm the spindle doesnt have enough time to return to center and it bumps&rides along the surface instead of having the opportunity to pierce the orange and peel the rest of the chip way
Imco 924 4 and 5 flute tools cut 304 and 316 like butter. Imco suggested speeds and feeds are dialed in nicely.
I've always used wiper inserts on stainless leaves a mirror finish. Some chip breakers make it look terrible.
I found that to as well, that basically Fusion 360 treats an Engraver as a Chamfer Mill. I may have discovered that in their Wiki. The benefit though, is that on a Chamfer Tool you can set all the parameters (like point angle, etc), to match the tool that you have.
Love 303, like 316, kinda hate 304. BUT I think that 304 when polished has a much better feel than any other material. I've recut all the balls for my machine handles in 304 and it just feels better. I don't know how to explain it. I have made a series of balls, 1 inch diameter in a myriad of different materials to test this and it's unanimous. A ball of polished aluminum or brass feels different than a ball of polished 304. I assume it's because the stainless holds heat better so your hand warms up the part instantly, where aluminum and other materials take longer to warm up by hand and feel cold. 304 takes a brilliant polish too. It's gummy and crappy to machine though.
As always great informative video, been watching since the beginning days in NY, I learn something in every video. I have had to do a lot of engraving in 304 and 316, I have tried a lot of tools and by far best tool Harvey 939716-C3 1/4" 90 degree .015 tip. lots of coolant and ramp in no plunge. I have cut .015 to .020 deep to fill with powder coat and the tool lasts a long time.
Exclusively machining 304 for a year the thing I learned was give it to er hard. Deep cuts high feeds.
Thin cuts on steel with carbide inserts are incorrect working conditions. You are forging, and hardening the surface instead of getting under it with a nice cut. Thing is with 304, it doesn't like heat, the surface melts and sticks to the cutting edge of the cutter, by doing that, it "chockes" the cutter, increase load and eventually breaks the cutter. Just avoid high rpm's ,full diameter penetration and full diameter plunges. Also use sharp edge cutters.
Fischer977
That’s not an issue when using high feed milling inserts which are specifically designed for shallow depths of cuts. Most high feed inserts max out at around a .025-.030 DOC. A .005-.010 is perfectly acceptable
that surface tip should be really measured perpedicular to cut according to Mitutoyo.
Sweet.
The only thing better than coolant is more coolant!!
Cobalt works well. HSS steel needs TIN on it.
how about deeper cuts and bigger endmills?I need help with that trying to face off .1 off the back of a part and having trouble
I find it funny how I see multiple American jobshops go around stainless steels and even harder materials saying they're hard to machine. I'm a schooled machinist and I haven't had any issues with it at all.
Carbide is the only way to go for stainless and up, preferred with a coating like TiCN.
And cooling, flood that endmill with coolant, it's a CNC not a manual mill
Agree.
Work with 304 and 316 on a more than regular basis - lots of coolant on carbide endmills. Carbide inserts on the other hand when face-milling; I usually run with air instead of coolant, as the thermal shock will crack the inserts faster instead of letting them transfer the heat. At least from my experience after years of trial and error.
The main issue I have with stainless is the tension that builds in the material once you machine it - especially on long/plate/thin parts :P
Oh man, here come the, "In Europe we do..." bullshit comments.
@@PatrickJoergensen the tension is in all materials but yea stainless really is a bitch, I always try to work towards the center in stainless. Prefer running a program a few minutes longer then having to make 10% extra for the warp that's going to be introduced
@@xenonram haha well you call it European bullshit comments, I call it America needing to reinvent a wheel because it's America. It's stainless not some rusty tin can that you could machine with your shoes. Get some decent carbide tools and flood them cause it's gonna get hot
René Honsbeek we do not have problems machining any materials especially stainless steels. Thanks
Ha! I’m pricing a job for 304 right now...is Johnny 5 already on the grid watching me?
NEED INPUT
304 turns like butter seco inserts 1000 sfm no problem looks real nice
Hum. Aren't you measuring your Ra (roughness) parallel to the cut?
I always use a bore nose the mill carbide
Can you mill me a stainless steel corn cob? I need one, about 10". Thanks
Fusion 360 doesn't let you program a trace with a centre drill? I use HSM works (which is the same thing) and that lets you use a spot drill for tracing.
Spot drills and center drills aren't the same thing in Fusion and HSMWork. So yes a spot drill works. A center drill doesn't.
Is it possible to engrave that material 3 mm ...?? Should I use the same tool...?
I make saw blades that cut right through that stuff.
Hello John
How are you? I need your help John please.
I have a problem with my fusion 360 I cannot see tool display when I want a new tool selection ?
Have a nice day
Is 304 stainless steel flexible at .025?
Is that a first ? ;)
dam it
beat me to it
SS 316L ?
Man, only posted 3 minutes ago and a dislike? Must be slow at work for the trolls.
I feel its the use of "pro tip" without including credit to the pro in the same statement that turns some people off. This "pro youtuber" has just busted a bunch of tools and wants to share what he the other machinists that work for the company ended up doing, would probably go over better. Sorry but I was actually busy with work today! not at work, I don't work for someone else haha.
I spend the last year milling and turning it and it is so shitty material especially when you hove to slot it with 3mm endmill. I prefer 303
Tried 321 ?
Sorry, I'm not man enough to face 304 stainless yet.
Coolant, that is your surprise? Like its unexpected and counter intuitive? Really? You mean coolant on a metal that builds up localised hotspots did something? Come on dude.... that was in the vid just to increase viewer retention. It was a cheap trick to help your numbers.