Endemol the goal of this video is to come up with a good recipe so let's walk through why and how we selected this particular end mill to start with how we get that initial success recipe and then how we grow from there to get a recipe that meets the goal whether it's process reliability ie just not breaking the tool higher removal rates or surface finishes and we're gonna do this testing on two separate machines mostly because one has a fog buster and the other has flood coolant and when we're slotting and when we're cutting the same with Steel it's a pretty big difference let's dive in when you have a specific application especially a more challenging one like slotting and stainless steel it's worth ensuring that the tool you picked is designed for that process helical makes that easy we'll go to products by material stainless slotting what's relevant for stainless steel is that usually the grind on an end mill designed for stainless steel is quite different than it would be for a tool steel or a mild steel we're slotting so the best options are a for flute chip braking rougher a flute variable pitch or a for flute variable pitch from experience I've found especially with the smaller diameter end mills like a / inch fewer flutes is they better option because fewer flutes means there's a larger gullet which means there's a larger area for that chip to form and then evacuate and usually what kills your tools in sliding is recutting those chips because they haven't been evacuated so flute variable pitch we have two options corner ease or square if a corner radius is acceptable I recommend it we're going to go with the option that has a ten thousandth of an inch corner radius so it's quite small for most of the work we do that's more than acceptable and that corner radius makes the tool stronger by getting rid of the weakest point of the tool which would be the sharp tip on a non radius end mill I've got two options with different lengths of cut I'm going to go with a shorter length of cut because with slotting that's generally going to be the limitation so I wanted the most rigid tool possible the shorter length of cut means shorter flute length which increases that rigidity so two three zero one to get some initial speeds and feeds there's two different thoughts on this you can look at standard speeds and feeds charts that most manufacturers come out with we've got some starting speeds if these recipes over on NYC CNC there's also just sort of a general rule of thumb of usually you're not going to cause a problem starting in the two to three hundred surface feet per minute and say one thousandth of an inch feed per tooth but this is stainless steel and it's slotting I'd like something a little bit better and the machining advisor probe gives us a good starting point for that I'm gonna skip material and instead choose the subgroup type three O floor tool path is slotting got a pick and yield on the material er ten thousand will say one hundred so the starting recommendation is surface feet which is rpms at half a foul feed per tooth or eleven inches per minute the first thing I like to do is then see what's the range of recommendations if I produce the speed which will increase to life and I reduce the feed for less deflection what I'm really doing here say what's the most conservative version of this recipe it's dropping the surface of speed down quite a bit but it's only reducing our feed per tooth by one ten thousandth of an inch however don't fall victim to disregarding numbers just because they're small dropping it from five tenths to four tenths is still a percent reduction the last thing I'll check is what happens with workholding security we're reducing it would drop the feed rate another ten thousandth of an inch it's worth thinking about we actually have pretty good work holding security in this setup but again I'd like to understand what does the software trying to tell me because it's not just the piece of material on the device but the overall rigidity of the machine tool and the tool holder hopping over to fusion to canvas up got my slot model I'm using the axial recommendation of point one inches or % of the tool diameter one of the things I like about Harvey and helical is that many of the tools are available for fusion they don't come down loaded we'll put a link in the video description you can download the latest version of those libraries and what that lets us do is type in the EDP number and drag it over to this file only I don't like is it doesn't default to any meaningful starting recipe speeds what we want to do is pull those out of map so we'll start with and for ten thousands of an inch d contour and select our tool and I'll click on this inside edge to create a slot because sliding is a hundred percent width of cut it won't matter which direction you go but I care because of our coolant lines especially on the fog buster so I'm actually gonna use this edge because that's gonna move the tool from the front to the back that has a better point of aim on our fog Buster nozzle click ok so we have a blinking move that I don't like it's got a -degree move right at the start of the part which will probably break the tool so let's fix that will change the lead and sweep angle from to zero that will move the tool straight into the part instead of coming from the side but I'm gonna increase that distance and there's two ways to do that I can increase it by the linear lead in distance say make that point one inches that will cause the tool to move in further and because I have the lead out check and it's matched to the lead in it will lead it out point one inches on the tail and that's more than you need but I like to see the tool move a little bit before it moves into the cut especially when I'm testing a recipe the other thing you can do to extend a tool path is under geometry you can choose tangential extension distance it does the same thing with one difference the tangential extension distance occurs at the cutting feed rate the linking moves occur at the linking feed rate for most of us it's often time that those feed rates are the same but you do have the ability to change them that went great listen to the machine I didn't hear any inconsistencies it's one way of telling if it's recutting chips we have some good chip evacuation so the second cut will run at the base recipe out of the machining advisor Pro no problems with cut - so where do we go next we can't actually adjust the width of cut because we're slotting we can't go less we can't go more so we can either adjust the depth of cut ie axial depth or we can adjust surface speed aka rpm I'd like to try axial depth for two reasons number one increasing the surface speed would do so at the potential benefit of going faster but at the cost of either decreasing tool life or it doesn't say it here but higher risk of chatter or breaking the tool the other factor is that at , rpms we're definitely not near the , RPM max but I think we'll be able to get a better bang for our buck or more removal rate by testing the axial depth of cut mostly because it were only at % of the tools diameter right now and with slotting oftentimes you can get up to % depends on a bunch of factors and criteria and how would you know that if you weren't a machinist well some of these things you just have to learn over time ironically it's the PDF the the standard feeds and speeds from helical here that does mention full slotting they recommend the axial depth of cut being to percent so we're only at or even half their recommendation so for the next cut let's step this up to a hundred percent other thing that's important to note when we're testing slotting like this is at the length and direction of the slot you're testing with needs to match your end goal in other words don't test on a one or two inch long slot and then expect it to work in a or inch long slot or time in the cut likewise we're testing the slot along the y-axis move here if your slot is actually a long x-axis or a different angle in this setup particularly that's going to have a huge impact based on the ability of the fog buster to have helped evacuate those chips [] no problems on that cut but if you notice I was trying to make sure that coolant line was perfectly aimed at the slot and I bumped it out of the way for a split second I'm honestly surprised the tool didn't break because recutting chips will often lead to pretty quick tool failure so where do we go from here we could increase the axial depth of cut to say or percent the concern there especially with the fog buster is usually I'm not sliding in a straight line and I may not always be paying attention to where my fog buster is aimed and as you increase that depth of cut more of the tulle is hidden inside the slot which makes it all the more difficult for the fog buster to help aid and ship evacuation unless it's perfectly aimed at the backside of the tool so the two other variables we can play with increased service footage or increased feed rate the feed rate doesn't move that much from / up to / although that is a % increase so it can run a little faster and this is a time where you've got to decide what's the most important thing for you is it not breaking the tool or is it being able to walk away from the Machine and know that it may take a minute or two longer but it should be a recipe that works let's keep the axial depth but try one more recipe where we bump up that feed rate to the cents per foot taking a look at the tool under microscope looking to see if there's any problems for example fractured coding or actually cracking on the insert of the edge don't see anything that really bothers me you can tell the tool has been used that's okay I've made a few test cuts with this tool prior to filming but that's one of the differences between a stainless steel tool and a steel end mill is stainless steel benefits from having a sharper tool it's that sharpest that helps share the stainless whereas a tool steel or steel end mill may have a slightly honed a rounded edge that gives it more toughness but what that means is that if I lose that sharpness it's likely going to result in the end mill failing there's no guaranteed tool life at all but I also hate it when people won't tell you or give you some idea so here's what I would say in aluminum with free cutting good chip removal you may get dozens of hours of cutting in the cut go to the extreme opposite on a material like inconel you may be lucky to get twenty minutes in the cut so with a tool like this in stainless steel i would think something like thirty minutes is probably a pretty good expectancy for time in the cut it could well be more but to get more out of it I'm guessing you're gonna want to do things like even less run out something I got through spindle coolant or something that even guarantees better chip evacuation and again watching your overall speeds and feeds and service figures just to give you some idea of what you might think is a good successful life out of that tool let's see if we can increase the axial depth of cut to a hundred and fifty percent you'll notice as we make that adjustment in math it recommends that we reduce the feed rate down to four ten thousandths of an inch feed per tooth or ten inches a minute if it fails we'll move over to the m and see if it's the chip evacuation or coolant that makes the difference let's see how this goes number one I'm gonna just turn my cooling on just double-check I like where the who it is washing it's the stream literally the stream of a bride if we break this tool here I suspect it is because of the core system mean I think the tool itself can probably handle this cut but not if it's not enable to evacuate chips and we have our fog Buster turned up a little higher than normal it's about psi again the higher pressure is going to help evacuate those chips okay the tool broke using the fog buster let's move over to the M with flood coolant and show that we're going to be able to push this tool harder because of the flood cool [] okay % depth of cut worked fine with the flood cool let's step up to a hundred and twenty five percent axial and let's reduce our feed and speed to hopefully stack the deck in our favor and get a successful cut / feed per tooth and surface fee same feeds and speeds but the key with slotting is you've got to test the length of the slot and if the tool is changing directions everything we've done so far in this video is a bit a four inch slot where we're only cutting along the y-axis when we move directions two things come to mind number one does your machine behave differently being a condition of the Gibbs or the linear motion system more importantly though is going to be the coolant does the court have the same access to flush those chips out is it running off for some reason is it being blocked so this test will prove out number one can the tool survive longer in the cut and number two can we turn a corner can we change directions this is cut ten hundred seventy five percent depth like I really expect this will break but that's okay we're gonna if it does it does [] are you kidding me that's incredible % axel depth I've got a spoiler alert we break the tool take a look and see if you can see why the tool breaks [] I think the tool and the tormach were both capable of this cut what happened is we were cutting at the edge of the part so the coolant is hitting the side of the part not the face the part where it needs to be hitting to actually provide that flushing action the same thing almost happened to us when we were cutting our longer slot lengthen the cut slot so those are the things that you've got to think about when it comes to the process reliability and not just living in a theoretical world of CAD and cam and feeds and speeds but really that was your part setup and how are those coolant lines working I was surprised at how well percent depth work but when it comes back to process reliability I would recommend Sikkim with a hundred percent depth maybe the or what is imperative is your coolant cooling us three things it evacuates the chip it lubricates the cut and then actually provides a cooling effect all three of those factors are important but it's the recutting chips or the chip evacuation especially slotting a stainless steel that's going to most likely lead to an immediate tool failure the fog buster works great with that air blast and the mix except that you can't always have your fog buster pointed directly at the trailing part of the tool path stepping up to the dual head fog buster could help but here flood coolant just wins it's just better if you want to up your process reliability or push this harder upgrade to a higher pressure pump add more nozzles or you can see on this tour mock here the nozzles stop at about four or five o'clock that's to accommodate the ATC if you're not using an ATC modify that to have some flood coolant nozzles come around or make a ring so that you're flushing from all areas only time I don't like flood coolant is when it's really low pressure and or you're doing a big pocket where it just creates a swimming pool for the chips to hang out in because then your recutting them the last takeaway is that it can actually be helpful to have a little bit more stick out on the tool here you know that's very counterintuitive normally that means keeping the tool as short as possible and using the shortest flute length as possible here the benefit you gain from having a little bit more stick out helps aid in the ability to get flood coolant or the fog buster better for chip evacuation and that benefit absolutely outweighs the sacrifice in rigidity a lot of the work and research that we're doing here is what we're feeding into our new speeds and feeds website proving cut proven cut offers you video speeds and feeds information so that you can watch and listen to the cut as well as one-click open the whole cam tool path and speeds and feeds into fusion to use on your part your project you can search by material by cutting to a by gauge length by tool manufacturer by machine weight a whole host of filters and criterias so if you're looking for better speeds and feeds check out proven cut otherwise folks take care see you soon
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