@@blarghblargh Hes insecure because he makes these mistakes / wasn't smart enough to think of them before watching this video which caused the snarky comment. I work as a machinist and all of this was true and I absolutely hate when customers send me blueprints for a machine and I can instantly see useless features I need to machine on many parts. I may get paid by the hour but I value efficiency and professionalism.
I love that at no point did you say "this will be impossible" or even "this will make things difficult for the machinist". Framing it as "this will make your part more expensive" is what people really need to hear to get it into their heads!
yeah, what's nuts is when people don't get that this is the primary reason the fillet tool exists... to model mating geometry that doesn't need a custom broach or EDM to make...
13:30 So, for small volume parts, if the corner radius isn't critical (i.e. they're just there to avoid hard corners. Handling, materials stress, whatever reason) include a note to the machinist "Exact radius not critical, pick a radius between A and B you already have a corner rounding tool for." Your part will be cheaper and they'll be happy you thought about making their life easy.
Another way to accomplish the same thing is to put a large tolerance on the dimension for the radius feature; something that should allow for a few tool sizes, but still works for your design. That approach tends to work better if your part is being made by someone that doesn't speak the same language as you. It also probably complies better with more modern drafting standards.
@@radtap break the corner with what though. There are corners I can break with ⅛x45⁰ no problem, but if I break a different corner with 0.005"x45⁰ I could ruin the part. You'd be surprised how often I'm asking for clarification on corner breaks or other seemingly minute things like surface finish, or tolerancing on features. Sometimes features that are important aren't dimensioned properly on the drawing for one reason or another.
@@staples156 This is a great way to do it. Always put the largest tolerances you can get away with. There's usually a "general tolerance table" specified for each drawing, so anything not specifically called out with a tolerance like R10 +10 -5 would have _a lot_ tighter of a tolerance.
There is SO much friction between design and manufacturing about things like this. I'd love for this video and more like it to be required watching for every new engineering hire. The opposite is also true of course. There are aspects to design that would greatly benefit many machinists to better understand.
One of the best things to ever happen to me career wise as a machinist was having a desk in the engineering office. The barriers came down and I really understood more about my place in making parts.
@@adamthemachinist My current workplace has the engineers, toolmakers and tool testers all sharing the same office space. add in leadership thats trusting enough to let every level do our own planning for orders of operation. most efficient workflow i've come accross yet.
When I was at the university to study mechanical engineering, the professors made sure we understood how parts are made and how to design accordingly. The best advice we got was: "Whenever you start a new job as a designer meet the people on the shopfloor and understand what they can do and what not. And whenever your desing is 80% done, show it to the guys at the machine and ask them how to optimise it for manufacturing". I follow these rules and in 15 years of designing complex mechanical parts for the automotive industry, not one of my designs failed a review by the supplier.
I see this as a structural engineer too. Problem is, the guys doing the work are even farther removed from me than a machinist is to the mechanical engineer.
@@tippyc2 Ask your boss to send you on site once a month. The travel expenses are nothing compared to what you can save when you desing with the reality on the construction site in mind. It's likely that they spent extra time one working on details you really don't care about or that they are able to do things you didn't know about.
@@Splarkszter that's why I always put an apple like G3 curvature chamfers. Come at it with a ball nose and make it a 100 passes. I want my corners to be smooooooth
I am not from a toolmaking community. I am from academia. Throughout all my years on mechanical engineering I noticed ME students do not understand some principles of design. I even wrote a syllabus of the course I called Applied mechanical design. The problem for the designers is in many cases they have no idea of how the part is going to be machined, what ready tools they can get, and what tools they need to make. Once I got a drawing from a student with a threaded hole close to a wall. I asked the student how it can be done, what tools and what a sequence. The student had no idea. Another issue is tolerances. You can not get on plastic same tolerance as on steel. They make in CAD same diameter hole and pin and expect it will fit when machined. Thermal expansion, surface finish etc. Unfortunately, young engineers are not ready straight from university for real design.
Having just graduated with a mechanical engineering degree, I totally agree and I think it's mostly because programs don't put much time or emphasis into getting students actually making parts. Our only required machine shop classes were pretty basic, and I think the most experience anyone got making things was doing engineering extracurriculars that required fabricating custom parts.
That's why is make sense to attend a university or college that requires practical experience as part of the curriculum, e.g. internship semesters. Might be a less fancy degree from a less fancy school but the students are better prepared for the work place. Additionally, in the USA, a university will rarely tell a student that they do not have the aptitude for a certain profession (since they want the student's tuition) whereas an industry professional will let you know. Parents should look at the rate of job placement after graduation rather than the name of the school.
I still say the most useful job I had as a student was working for my university machine shop for the summer. Learned so much in just 4 short months of the various things they had me do. I wasn't completely green with actually making stuff then, I had done a fair bit of woodworking in high school, but it is so hard to teach someone to think that way without actually having them take raw stock and figuring out how to make the end product. As someone that now hires students for work terms now I definitely appreciate those that are part of student teams or have other hands-on experience as they tend to be much more capable designers and problem solvers.
Props for encouraging students to actually understand the manufacturing process - it's great to see that kind of leadership come from the academic staff. When I was studying engineering, we spent three or four weeks in a machine shop completing practical units from the mechanical trade qualification. It was really useful - especially for the students that didn't have any hands-on experience making things. Unfortunately, my uni stopped offering that to students a few years after I went through.
If you're handing out the Standard tool cards you're doing god's work man, and to be fair, even my peers in machining classes sometimes underestimate just how deep threads actually go...
Scrolled for a while and didn't see it mentioned. Fillets are very usfull for making parts last longer, sharp corners are stress concentration points that will lead to early failures. Really excellent content for making fillets easier for the shop to make.
A small addition for the folks at home on the radius at the bottom of a pocket, bull nose endmills come with standard and preferred radii. Use those! Preferred wherever possible, a non preferred standard size if you must, and be prepared to pay in lead time and part cost for non standard nose radii. Getting cutters custom ground takes time and money. Don’t know which size is preferred? Ask your friendly neighborhood machine shop foreman. They’ll have opinions. Actually, that goes for almost all tooling.
"Ask your friendly neighborhood machine shop foreman" been there, done that. And than the purchasing department ordered the part from a job shop in south east Asia. 🤣
Sticking to standard size tools is a great way to save time and money. Even better is not letting the intern specify a .001 tolerance on all dimensions.
@@8__vv__8 As one of the engineers sending out CNC jobs, I apologize on behalf of my colleagues. I WISH it were just the interns.... That said, you can tell my opinion of someone depending on if I refer to them as "Kevin" or "Intern Kevin"
@@november382 As a retired Tool Room machinist, Tool Maker and machine rebuilder l dreaded every single time l saw a print that featured tolerancing "errors". By errors l mean the use of tight tolerances on inconsequential features. Non standard sizes on C/Bored pass holes for SHCS's. This can mean the extra step of interpolating the C/Bore, having special tooling ground or expensive setups on manual machines. Tight hole sizes on pass holes with a +/-.005 on location. The use of specific hard to setup off of features as Datums. Ideally we always wanted to machine everything to nominal. Another thing that l did not care for was high surface finish requirements when the designer knew we were dealing with shop equipment that was severely worn. In need of replacement or full rebuilds. The replacement of worn out shop equipment is a pet peeve of mine. Yes one can do good work on worn out machinery. But it takes longer. I worked in an engine plant. Every time the engine assembly line was down for one complete engine ready to ship was around $1500 iirc. The bean counters could not understand that a $15,000 Bridgeport type mill w/CNC control only had to be able to do the work needed to get you back into production for 10 assembly cycles to pay for itself.
Thanks for sharing your knowledge! I really like how your demo part had a corresponding "do this instead" feature on the opposite side. The only thing that could have made this video better is a construction paper demo 😉
I just learned more in 20 minutes than I did over a week of college courses. Incredible that this stuff isn't taught in depth when you are becoming an engineer, it's touched on briefly but not the the extent it should be. Please keep the knowledge coming!
I was talking about this only a few days ago. Turning your brain off and making near impossible geometry in CAD is far too easy and I’m guilty of it too! An insightful video as always
I’m a mold and die maker. This is great knowledge to those who have no idea. Another idea I can think of is when you need grind stock on an OD or ID with a radius at the bottom. You’ll need to hard mill or grind that radius after heat treat because your cutter cannot produce said radius when the wall has grind or hard mill stock on it.
i'm doing an adult apprenticeship as a machinist. had to set a job this week where the design engineer truly loves the Radius function in CAD. Clearly they have no idea what happens between sending off their CAD model and getting a part back. thankfully they're a good client and this is a prototype job, so we can *try* to influence final design a little.
This really resonates with me, when reviewing my junior engineer's drawings and designs they forget to think about how it's made. And I can sympathize, when I was a young engineer I was too concerned and obsessed with the perfection of the design and didn't want to compromise my design for the sake of manufacture. After working many years and having to CNC my own parts, I now want to design things that are easy to manufacture and get the job done, could the part be more perfect? yes. Will anyone manufacture it for me at the cost I want? No.
Making it easier to manufacture will generally also make your machinists happier. Instead of cursing that engineer that had them spend 10 hours to get _that_ feature just right. _Especially_ if it didn't even need to be that exact. Give things the biggest tolerance you can spare, your parts will be cheaper, and most machinists will try to get it _fairly_ close to nominal anyway. If you give a machinist +-1 mm on a pocket with side lengths ~50mm it's doubtful that it would end up close to either end (unless usinga "cheap" shop).
@@TNH91 that's near the gospel of GD&T. Give the parts the largest tolerance they can to still function. Although, anecdotally, I've had US based shops call my GD&T "space age" tolerances. They're the same shops that couldn't hit the broad side of a barn but still charge high end prices.
@@capnthepeafarmer GD&T? General Dimensions and Tolerance? I would say that those _often_ are tighter than necessary if the engineer/designer had taken a few minutes to think about it. Though they usually (if following DIN ISO 2768 or equivalent) are fairly easy to hit directly with decent machinery. Slightly more work when you have a tolerance of 5-10 µm in one direction.
@@TNH91 no no, GD&T is "geometric dimensioning and tolerancing" short hand for the ASME Y14.5 standard or the ISO GPS standard. Not the same as the title block tolerances or the general tolerance of ISO2768. GD&T was developed in the 1930's so torpedos from different manufacturers could fit in the same hole. Just by virtue of having GD&T doesn't make anything more precise. It only specifies unambiguously the datums and the relations to features. It's up to the designers and engineers to specify the widest tolerance that makes those parts functional. That's why mass produced parts use GD&T with wide tolerances, but you can also use GD&T on very precise parts. It's just a way to unambiguously specify the relation between features so anyone can manufacture it.
This was so educational for me. I know nothing about CAD / CAM. I've watched ToT do an intro, but this gave way deeper insight to the challenges and style of thinking that a pro has to become fluent in. It's why I love this channel.
Yeah this was great, thanks! I'll be sending it to my colleagues. You highlighted a few extra gotchas I hadn't thought about before. (Also emphasizes the value in having designers make their parts/prototypes every once in a while to really hammer home these concepts)
Excellent overview and friendly resume of things to watch out for when drawing up CNC parts, much appreciate the friendly and helpful overall tone of the video. Expressing things in a matter of cost is a beautiful way to get across the intricacies of engineering to people who have not worked with the wonder that are CNC machines.
This same vid on tolerances would be great. Tolerances in different materials like steel to plastic. I run into parts as a toolmaker that are held 5 10ths and are plastic a lot. I do best I can but I know it usually will grow later when it’s just sitting in the shelf.
Another option for wire EDM in a corner is to cut into the stock to leave no radii on the corner. For the 90⁰ example, if the wire cut into the stock the depth of the wire at a 45⁰, you're left with an undercut but the mating component can maintain a sharp 90⁰ edge without interference.
@@fergusoddjob It would be a specific feature, for example the relief in a v-block. Also, it doesn't technically need to be the full depth of whatever cutter you're using, but full depth would be more than safe, especially to make sure that debris doesn't clog it and stop it from functioning. The one issue with this is that it is a more significant stress-raiser, so you'd want to be aware of it as a potential issue.
I really appreciate this as an engineer recently out of school. School weighs much more heavily toward theory than practice, so this is the kind of knowledge that seems obvious once you think about it, but just hadn't occurred to me before.
Just subscribed! Loved learning about opening up the internal radius to minimize flute engagement as well as accommodating the .500” endmill. Very valuable information for a design engineer to know
I've never touched a machine tool, and although I screw around in Fusion 360 for fun sometimes, I've never had a part manufactured. But still I absolutely LOVE this content. It satisfies that itch to learn new stuff in an arena I find interesting. And you explain/present it sooooo well. I'm subscribing. Thank-you for your efforts!
Would definitely love to see a heat treat design video. I've always wondered, and shyed away from heat treat shrinkage etc design. Thank you for the awesome videos!
This was one of the best guides I have seen made for designers about fillets! Thank you for taking the time to put this together. I wish I could send this to all my customers! I would really appreciate a heat treated part video. My department at work is starting to get some work in that space, and there is definitely a lot of things that I don't know I don't know. I would love to learn everything you have to share about that topic!
I came for the title but I stayed for the practical advice. As a mech E and self taught machinist, this information is invaluable for a new design engineer. Also tons of new useful tricks for me 😊
This video is really informative and you are a good teacher. You should make a series related to this topic; design for manufacturing. No one is teaching mechanical design engineers about the information you give here. You earned a subscriber. Please make more videos like this one.
I like the design for manufacturing information. Different issues but I do the same type of thinking when designing for 3D printing. I really wish we had gone metric in the US. I design metric but often use Freedom Unit tooling for cost as you stated.
Hey, as someone finishing up my last year of school as a mechanical engineer, this video is awesome. I’m lucky to have a good bit of experience machining in the past year and a half, so I understand the difficulty with fillets already; but I would have loved this video even 2 years ago when I had no idea how machining and manufacturing worked.
Gotta say this was awesome. Extremely practical content. I'm just coming out of my apprenticeship in Aus and so much is taken for granted in explaining, especially as the quality and tolerance demand increase. More of this "but how would you do this" content would be very welcomed. Maybe grinding, surface finishes, materials, maybe where to find or how to apply refernce info (like how would you determine draw die depth and radius, and the real exciting things are the topics i haven't thought about yet.
Amazing video I’m for sure going to use this video to explain fillet design to customers. Seams that I have this conversation with customers to often and they never seam to really understand what I’m talking about.
I would add, sharp inside corners on large parts like the inside of an L shaped part, if you can just throw a "Allowable radius" callout in the corner, that way it can be made during profiling, and doesn't need to be floor machined from a different orientation
This is a fantastic video - I do mechanical engineering, and while I knew some of these, several of your points here I had never considered before - particularly the 'sharp corner' on the bottom of the pocket being a pain. Thank you so much for sharing your insights! I would be keen to hear your thoughts on heat treating as well in a future video!
I know a decent amount about making things in CAD, and admittedly my manufacturing expertise is limited to 3D printing, but these are some very important considerations to understand that I will definitely think about when I start moving into working with machine shops for metal.
On the other hand for waterjet/lasercut parts rounds on all the edges shortens the cut time and makes it cheaper. Design for manufacture is such an underrated skill people need excellent work!
Very good video. I'm learning as machine design engineer, but I spent a little time with CNCs and regular mills/lathes, but even so I wouldn't take all of this into consideration (simply because I haven't use every tool mentioned here). It is probably EVEN MORE useful for people who don't have experience on machining. Such things should be taught in depth for every engineer who's likely to design anything, but I mostly see it taught to people who specialize in manufacturing.
Thanks for this. Any information that leads to smoother interactions between designers and vendors is a net positive for the world. I'd love to watch similar ones on heat treats, coatings and welding considerations.
I've been sharing your videos with my coworkers in the design department and they are loving them. You help break down the manufacturing process so we'll for the is such digestible bites. This video is going straight into the teams chat for the to watch as required material on Monday.
I have lots of machining experience from working as a die maker in my first job out of school. That experience stuck with me so much that when I’m designing a part at work now, my design tree always starts with a block of stock and gets carved out in operations like I’m machining it in CAD. I rarely get calls from the machinist asking to clarify anything.
Such a great video, having the clear examples of so many corner types in 3D, plus the toolpaths, is a fantastic way to teach these ideas. For sure this is getting bookmarked and shared with every junior designer I work with! I would like to learn more about heat treating. Also I (medical device designer) would be interested in the kinds of tolerances you see that cause you headaches. I know you like your fancy inspection setups too so perhaps your least favourite tolerance types to machine and least favourite ones to inspect?
Thanks Adam, that was a great video, with the interactive CAD explanations. Something similar on heat treatment would be great. There isn't a lot of good concise information about on this all in one place. Always appreciate your video content 😊
Great presentation, Im only a hobby machinist witj a nome built cnc , but use commercial fusion licence and man I love the way you can preview the too path so concisely.
Great video as always Adam! This kind of information so incredibly useful for people just getting started in the industry and we really appreciate you sharing your knowledge. My school did a better job than most teaching design for manufacturability, but still never covered these kinds of details. Keep up the great content Adam!
Great tips. As a maker I love this kind of content. Even though I live in the US, I design everything in metric (as most of the parts interface with other metric parts, such as the current heat-sink for a Raspberry Pi) so those size tips really help. A guide sheet would be most helpful when designing parts. I admit my cost guide for features are the instant estimators from Protolabs and Xometry. That is an easy way for me to see if a particular feature is worth doing based on how much added cost it has.
Thank you this was very helpful for me going from designing for 3D printing to designing for machining. I just learned from this video at there is a lot to know about the geometry and the physics of machining to be able to design so a part can be made economically. I just bought an old Novakon 145 CNC mill and lucked into a Microkinetics 1236 CNC lathe missing the electronics. Installing Centroid Acorn to replace Mach 3. I have limited experience with milling machines but have owned a metal lathe before. I need to watch more of your videos because at this point I don't know what I don't know about milling machines.
Heat treating video would be much appreciated! Designers must know what constrains manufacturing processes have. For example 3D printing can do beautiful fillets. But at which orientation will it be optimal? Which additive process will be used? What percentage of the cross section can you expect to actually distribute the load? ... This is why I think it's important to have a multi-disciplinary CAD-CAM-CAE softvare like Siemens NX or Autodesk Fusion, so that even less experienced engineers can design, validate and properly optimize parts before pissing off manufacturers... XD I love videos like these culminating many years of experience! Yours are true gems, keep up the good work!
I only run a CNC router, but this video is really helpful in my trade. It's kind of hard to estimate how long a one off job will take, especially since I usually need to draw it in a CAD program myself. It's always these kind of corners that cause a time suck. Thanks!
5:48 another thing about machining these internal radii with a direct match sized cutter is the tool path, its taking a very abrupt 90 degree corner as apposed to a smoother path (some controls don't handle the abrupt corners very well and can cause form issues ), the amount of tool pressure and aggressive tool path combined smells like broken endmills.
A heat treat and/or surface treat video would be great. I’d also be interested in a video about the limits of CNC tolerances with catalog tooling. What can the machinist’s setup realistically achieve without being a huge headache?
Just love all of this. Learning a bit of both design and machining. Got a small mill and shop and Amy trying to start up my own thing and man do I have a lot to learn.
Very helpful. Thanks. I often get the opposite as well. Thin parts that could have the entire perimeter milled out in one go, but the engineers decided all the internal corners need to be dead sharp. So that turns a one set up job into a three set up job, then they complain about it taking too long. Lol. Engineers are a fickle beast.
"Design for manufacturing" (as well as "design to cost") is something many universities fail to teach. @all the engineers: Talk to the guys on the shopfloor! Ask them how to optimize your part for manufacturing. @all the machinists: Talk to the designers. Most of them don't want to make your day harder, they just don't know (although they should actually know) what they are doing
When you're talking about the pocket with equal floor and corner raii, you can get away with using a bull endmill. Try a floor pocket with the bottom of the radius selected as the profile and use a negative stock to leave equal to the tip rad on the endmill. Then constant step up ramp the floor rad. Depending on pocket tolerance you usually don't have to even do a wall finish profile, the ramp up surfacing pass will take care of the floor rad and the walls. If you do need the tolerance or spring passes or whatever, run a profile with the top edge of the floor rad selected and a negative axial stock to leave equal to the tip rad. It does for sure take more time to surface the floor rad, but it keeps it all to one single tool.
Very nice video! Just wanted to say that if you zero your radius cutter and touch off to the top of the radius, you can just mill at relative z zero. That way you don't end up going too deep by guessing how long the pilot/web is.
Hi Adam. Great video as always. If your looking for an idea for your next video, how about a video on blending toolpaths from different tools. You mentioned it here but I would love to hear you go into the weeds on the subject. Thanks!
Never thought about it as I come from the 3D printing world, but it's good to know. From a purely aesthetic point of view I think chamfers look better, anyway, and it sounds like that's not a huge issue for external chamfers, but you'll never get a tool with a sharp corner so I imagine internal corners are still a problem to think about.
dude!! +1million from a machinist!!! I can assure you that there is nothing worse than a long deep pocket with equal fillets on the floors. so much more work to get the floor flat because you have surface the corner floors. not a easy check box in cam, you have to create that on a part by part basis. and to make it look good you have to know some tricks to keep it from draggin the wall or chattering in the corners. id say overall takes at least 5x longer than floor with 1/3 or less radius than the walls have.
As a mechanical designer I often need to put some kind of corner treatment to make the model look good for the client. Since I do hobby machining I have an idea of what is easy and what is hard so I can avoid the really nasty stuff. Often times I will take a screenshot and go talk to the programer and ask what they want me to put so it's easy for them. Other times I put notes on the drawing or put low tolerances to indicate "I don't care about this other than cosmetics" On the other hand I will make a note "must fit with part XXX"
I would also like to add that designers should keep fillets standardized as much as possible. When it is just for cosmetic effect, there is no need to have four different radii that require 4 different corner mills or slow HSM milling with a ball mill.
Based on the first 3 minutes. You can tell this is just w hobbyist who thinks he's all that.
interesting. what specifically made you think that, and what is your experience level?
@@blarghblargh Hes insecure because he makes these mistakes / wasn't smart enough to think of them before watching this video which caused the snarky comment.
I work as a machinist and all of this was true and I absolutely hate when customers send me blueprints for a machine and I can instantly see useless features I need to machine on many parts. I may get paid by the hour but I value efficiency and professionalism.
@@Suomiwimbula Adam is obviously an expert. I love that he pinned that "genius's" comment for us all to see.
I love that at no point did you say "this will be impossible" or even "this will make things difficult for the machinist". Framing it as "this will make your part more expensive" is what people really need to hear to get it into their heads!
Personally, I don’t really mind a part with a ton of fillets that I need to 3D surface machine. Thats easy money.
I beg to differ. A pocket with square corners is how you make your part super expensive.
yeah, what's nuts is when people don't get that this is the primary reason the fillet tool exists... to model mating geometry that doesn't need a custom broach or EDM to make...
EDM🤷
@@DSiren CNC broach them. Get your Z axis paying it's way.
@@AndyRRR0791 Why would you when you can just fillet?
😂
13:30 So, for small volume parts, if the corner radius isn't critical (i.e. they're just there to avoid hard corners. Handling, materials stress, whatever reason) include a note to the machinist "Exact radius not critical, pick a radius between A and B you already have a corner rounding tool for." Your part will be cheaper and they'll be happy you thought about making their life easy.
Another way to accomplish the same thing is to put a large tolerance on the dimension for the radius feature; something that should allow for a few tool sizes, but still works for your design. That approach tends to work better if your part is being made by someone that doesn't speak the same language as you. It also probably complies better with more modern drafting standards.
@@staples156Yes! A wide open tolerance is much simpler than a designer overthinking it and adding specific notes.
Just tell them to break the corner, much simpler.
@@radtap break the corner with what though. There are corners I can break with ⅛x45⁰ no problem, but if I break a different corner with 0.005"x45⁰ I could ruin the part.
You'd be surprised how often I'm asking for clarification on corner breaks or other seemingly minute things like surface finish, or tolerancing on features.
Sometimes features that are important aren't dimensioned properly on the drawing for one reason or another.
@@staples156 This is a great way to do it. Always put the largest tolerances you can get away with. There's usually a "general tolerance table" specified for each drawing, so anything not specifically called out with a tolerance like R10 +10 -5 would have _a lot_ tighter of a tolerance.
There is SO much friction between design and manufacturing about things like this. I'd love for this video and more like it to be required watching for every new engineering hire. The opposite is also true of course. There are aspects to design that would greatly benefit many machinists to better understand.
One of the best things to ever happen to me career wise as a machinist was having a desk in the engineering office. The barriers came down and I really understood more about my place in making parts.
@@adamthemachinist My current workplace has the engineers, toolmakers and tool testers all sharing the same office space. add in leadership thats trusting enough to let every level do our own planning for orders of operation. most efficient workflow i've come accross yet.
When I was at the university to study mechanical engineering, the professors made sure we understood how parts are made and how to design accordingly. The best advice we got was: "Whenever you start a new job as a designer meet the people on the shopfloor and understand what they can do and what not. And whenever your desing is 80% done, show it to the guys at the machine and ask them how to optimise it for manufacturing". I follow these rules and in 15 years of designing complex mechanical parts for the automotive industry, not one of my designs failed a review by the supplier.
I see this as a structural engineer too. Problem is, the guys doing the work are even farther removed from me than a machinist is to the mechanical engineer.
@@tippyc2 Ask your boss to send you on site once a month. The travel expenses are nothing compared to what you can save when you desing with the reality on the construction site in mind. It's likely that they spent extra time one working on details you really don't care about or that they are able to do things you didn't know about.
This should be required watching for designers that want their parts made!
The designers who don't want their parts made should probably watch it too.
With a test to take after
@@donutfpv NO, LET ME CHAMFER, IT LOOKS SICK. DON'T TAKE AWAY MY CHAMFERS. I'LL RETALIATE BY SHARING STL INSTEAD OF STEP.
@@Splarkszter i will retaliate by actually using the tolerances you've put on your drawing.
@@Splarkszter that's why I always put an apple like G3 curvature chamfers. Come at it with a ball nose and make it a 100 passes. I want my corners to be smooooooth
I am not from a toolmaking community. I am from academia. Throughout all my years on mechanical engineering I noticed ME students do not understand some principles of design. I even wrote a syllabus of the course I called Applied mechanical design. The problem for the designers is in many cases they have no idea of how the part is going to be machined, what ready tools they can get, and what tools they need to make. Once I got a drawing from a student with a threaded hole close to a wall. I asked the student how it can be done, what tools and what a sequence. The student had no idea. Another issue is tolerances. You can not get on plastic same tolerance as on steel. They make in CAD same diameter hole and pin and expect it will fit when machined. Thermal expansion, surface finish etc. Unfortunately, young engineers are not ready straight from university for real design.
Having just graduated with a mechanical engineering degree, I totally agree and I think it's mostly because programs don't put much time or emphasis into getting students actually making parts. Our only required machine shop classes were pretty basic, and I think the most experience anyone got making things was doing engineering extracurriculars that required fabricating custom parts.
That's why is make sense to attend a university or college that requires practical experience as part of the curriculum, e.g. internship semesters. Might be a less fancy degree from a less fancy school but the students are better prepared for the work place. Additionally, in the USA, a university will rarely tell a student that they do not have the aptitude for a certain profession (since they want the student's tuition) whereas an industry professional will let you know. Parents should look at the rate of job placement after graduation rather than the name of the school.
I still say the most useful job I had as a student was working for my university machine shop for the summer. Learned so much in just 4 short months of the various things they had me do. I wasn't completely green with actually making stuff then, I had done a fair bit of woodworking in high school, but it is so hard to teach someone to think that way without actually having them take raw stock and figuring out how to make the end product. As someone that now hires students for work terms now I definitely appreciate those that are part of student teams or have other hands-on experience as they tend to be much more capable designers and problem solvers.
Props for encouraging students to actually understand the manufacturing process - it's great to see that kind of leadership come from the academic staff. When I was studying engineering, we spent three or four weeks in a machine shop completing practical units from the mechanical trade qualification. It was really useful - especially for the students that didn't have any hands-on experience making things. Unfortunately, my uni stopped offering that to students a few years after I went through.
If you're handing out the Standard tool cards you're doing god's work man, and to be fair, even my peers in machining classes sometimes underestimate just how deep threads actually go...
Scrolled for a while and didn't see it mentioned. Fillets are very usfull for making parts last longer, sharp corners are stress concentration points that will lead to early failures. Really excellent content for making fillets easier for the shop to make.
Internal fillets - yes. External fillets that don’t interface with other parts remove mostly dead material that carried no loads but had weight.
@@absurdengineeringexternal fillets can also help resist corners from chipping
A small addition for the folks at home on the radius at the bottom of a pocket, bull nose endmills come with standard and preferred radii. Use those! Preferred wherever possible, a non preferred standard size if you must, and be prepared to pay in lead time and part cost for non standard nose radii. Getting cutters custom ground takes time and money.
Don’t know which size is preferred? Ask your friendly neighborhood machine shop foreman. They’ll have opinions. Actually, that goes for almost all tooling.
"Ask your friendly neighborhood machine shop foreman" been there, done that. And than the purchasing department ordered the part from a job shop in south east Asia. 🤣
Sticking to standard size tools is a great way to save time and money.
Even better is not letting the intern specify a .001 tolerance on all dimensions.
@@8__vv__8 As one of the engineers sending out CNC jobs, I apologize on behalf of my colleagues. I WISH it were just the interns.... That said, you can tell my opinion of someone depending on if I refer to them as "Kevin" or "Intern Kevin"
@@november382
As a retired Tool Room machinist, Tool Maker and machine rebuilder l dreaded every single time l saw a print that featured tolerancing "errors". By errors l mean the use of tight tolerances on inconsequential features. Non standard sizes on C/Bored pass holes for SHCS's. This can mean the extra step of interpolating the C/Bore, having special tooling ground or expensive setups on manual machines. Tight hole sizes on pass holes with a +/-.005 on location. The use of specific hard to setup off of features as Datums. Ideally we always wanted to machine everything to nominal. Another thing that l did not care for was high surface finish requirements when the designer knew we were dealing with shop equipment that was severely worn. In need of replacement or full rebuilds. The replacement of worn out shop equipment is a pet peeve of mine. Yes one can do good work on worn out machinery. But it takes longer. I worked in an engine plant. Every time the engine assembly line was down for one complete engine ready to ship was around $1500 iirc. The bean counters could not understand that a $15,000 Bridgeport type mill w/CNC control only had to be able to do the work needed to get you back into production for 10 assembly cycles to pay for itself.
Learned something! Thanks.
Considering how Lego is manufactured to very nearly magical consistency, it is certainly a high bar to set for yourself.
Thanks for sharing your knowledge! I really like how your demo part had a corresponding "do this instead" feature on the opposite side. The only thing that could have made this video better is a construction paper demo 😉
The fusion illustrations of the cutter going into an inside corner were amazing, As well as the description of cutter engagement. Thank you.
Indeed, I would put Adams construction paper demos on par with PracticalEngineering garage demos lol
I just learned more in 20 minutes than I did over a week of college courses. Incredible that this stuff isn't taught in depth when you are becoming an engineer, it's touched on briefly but not the the extent it should be. Please keep the knowledge coming!
Engineering schools are businesses after all. This guy is giving it away for free!
I was talking about this only a few days ago. Turning your brain off and making near impossible geometry in CAD is far too easy and I’m guilty of it too!
An insightful video as always
Ok, now get back to work ;-)
@@wktodd Lo siento no hablo Ingles gracias
I’m a mold and die maker. This is great knowledge to those who have no idea. Another idea I can think of is when you need grind stock on an OD or ID with a radius at the bottom. You’ll need to hard mill or grind that radius after heat treat because your cutter cannot produce said radius when the wall has grind or hard mill stock on it.
i'm doing an adult apprenticeship as a machinist.
had to set a job this week where the design engineer truly loves the Radius function in CAD. Clearly they have no idea what happens between sending off their CAD model and getting a part back.
thankfully they're a good client and this is a prototype job, so we can *try* to influence final design a little.
This really resonates with me, when reviewing my junior engineer's drawings and designs they forget to think about how it's made. And I can sympathize, when I was a young engineer I was too concerned and obsessed with the perfection of the design and didn't want to compromise my design for the sake of manufacture. After working many years and having to CNC my own parts, I now want to design things that are easy to manufacture and get the job done, could the part be more perfect? yes. Will anyone manufacture it for me at the cost I want? No.
Making it easier to manufacture will generally also make your machinists happier. Instead of cursing that engineer that had them spend 10 hours to get _that_ feature just right. _Especially_ if it didn't even need to be that exact.
Give things the biggest tolerance you can spare, your parts will be cheaper, and most machinists will try to get it _fairly_ close to nominal anyway. If you give a machinist +-1 mm on a pocket with side lengths ~50mm it's doubtful that it would end up close to either end (unless usinga "cheap" shop).
@@TNH91 that's near the gospel of GD&T. Give the parts the largest tolerance they can to still function. Although, anecdotally, I've had US based shops call my GD&T "space age" tolerances. They're the same shops that couldn't hit the broad side of a barn but still charge high end prices.
@@capnthepeafarmer GD&T? General Dimensions and Tolerance? I would say that those _often_ are tighter than necessary if the engineer/designer had taken a few minutes to think about it.
Though they usually (if following DIN ISO 2768 or equivalent) are fairly easy to hit directly with decent machinery. Slightly more work when you have a tolerance of 5-10 µm in one direction.
@@TNH91 no no, GD&T is "geometric dimensioning and tolerancing" short hand for the ASME Y14.5 standard or the ISO GPS standard. Not the same as the title block tolerances or the general tolerance of ISO2768. GD&T was developed in the 1930's so torpedos from different manufacturers could fit in the same hole. Just by virtue of having GD&T doesn't make anything more precise. It only specifies unambiguously the datums and the relations to features. It's up to the designers and engineers to specify the widest tolerance that makes those parts functional. That's why mass produced parts use GD&T with wide tolerances, but you can also use GD&T on very precise parts. It's just a way to unambiguously specify the relation between features so anyone can manufacture it.
This was so educational for me. I know nothing about CAD / CAM. I've watched ToT do an intro, but this gave way deeper insight to the challenges and style of thinking that a pro has to become fluent in. It's why I love this channel.
Yeah this was great, thanks! I'll be sending it to my colleagues. You highlighted a few extra gotchas I hadn't thought about before.
(Also emphasizes the value in having designers make their parts/prototypes every once in a while to really hammer home these concepts)
Excellent overview and friendly resume of things to watch out for when drawing up CNC parts, much appreciate the friendly and helpful overall tone of the video. Expressing things in a matter of cost is a beautiful way to get across the intricacies of engineering to people who have not worked with the wonder that are CNC machines.
This same vid on tolerances would be great. Tolerances in different materials like steel to plastic. I run into parts as a toolmaker that are held 5 10ths and are plastic a lot. I do best I can but I know it usually will grow later when it’s just sitting in the shelf.
I work for a university shop serving students and professors. I will be sending this video in the future. Thanks!
Another option for wire EDM in a corner is to cut into the stock to leave no radii on the corner. For the 90⁰ example, if the wire cut into the stock the depth of the wire at a 45⁰, you're left with an undercut but the mating component can maintain a sharp 90⁰ edge without interference.
How would you call that out on a drawing?
@@fergusoddjob It would be a specific feature, for example the relief in a v-block. Also, it doesn't technically need to be the full depth of whatever cutter you're using, but full depth would be more than safe, especially to make sure that debris doesn't clog it and stop it from functioning.
The one issue with this is that it is a more significant stress-raiser, so you'd want to be aware of it as a potential issue.
This was brilliant. Hearing both sides of the discussion filled in a ton of gaps in my knowledge. Thanks for sharing!
I really appreciate this as an engineer recently out of school. School weighs much more heavily toward theory than practice, so this is the kind of knowledge that seems obvious once you think about it, but just hadn't occurred to me before.
Excellent tips, very helpful for me. Thanks Adam. You're content is awesome. Would love something on heat-treating!
Just subscribed! Loved learning about opening up the internal radius to minimize flute engagement as well as accommodating the .500” endmill. Very valuable information for a design engineer to know
Yeah but they make my 3d prints look siiick.
Thought the same thing!
They also let your printer continue around the corner without slowing as much as a 90.
Yeah I fillet all kinds of stuff when 3D printing 😅 but machining? Engage chamfer mode.
Fillets take extra time on reductive manufacturing. Fillets reduce time on additive manufacturing, unless it causes a need for support structures.
A lot of things still apply to 3D printing. Doing horizontal fillets in a pocket will also look terrible when 3D printed with any sane layer height.
I've never touched a machine tool, and although I screw around in Fusion 360 for fun sometimes, I've never had a part manufactured.
But still I absolutely LOVE this content. It satisfies that itch to learn new stuff in an arena I find interesting. And you explain/present it sooooo well. I'm subscribing. Thank-you for your efforts!
thank you for talking about backlash and kinematics. these discussions are rare and welcome.
Would definitely love to see a heat treat design video. I've always wondered, and shyed away from heat treat shrinkage etc design. Thank you for the awesome videos!
Mechanical engineer here… please make more vids like this!! It helps engineers like me who didn’t have exposure to machining!
This was one of the best guides I have seen made for designers about fillets! Thank you for taking the time to put this together. I wish I could send this to all my customers! I would really appreciate a heat treated part video. My department at work is starting to get some work in that space, and there is definitely a lot of things that I don't know I don't know. I would love to learn everything you have to share about that topic!
I came for the title but I stayed for the practical advice. As a mech E and self taught machinist, this information is invaluable for a new design engineer. Also tons of new useful tricks for me 😊
Yes a video on micro mecheaning and heat treatment would be super useful. Great video.
These videos are gold. Im here 100% for this DFM content. Super valuable! Thanks very much for your time in making them.
This video is really informative and you are a good teacher. You should make a series related to this topic; design for manufacturing. No one is teaching mechanical design engineers about the information you give here. You earned a subscriber. Please make more videos like this one.
Very helpful video, thank you. The nice rule of thumb numbers about diameter to length ratio are very helpful
I am a very experienced machinist video watcher and this was really interesting and enjoyable!
Heat treat info and thread depth would be interesting.
I like the design for manufacturing information. Different issues but I do the same type of thinking when designing for 3D printing. I really wish we had gone metric in the US. I design metric but often use Freedom Unit tooling for cost as you stated.
Hey, as someone finishing up my last year of school as a mechanical engineer, this video is awesome. I’m lucky to have a good bit of experience machining in the past year and a half, so I understand the difficulty with fillets already; but I would have loved this video even 2 years ago when I had no idea how machining and manufacturing worked.
Gotta say this was awesome. Extremely practical content.
I'm just coming out of my apprenticeship in Aus and so much is taken for granted in explaining, especially as the quality and tolerance demand increase.
More of this "but how would you do this" content would be very welcomed. Maybe grinding, surface finishes, materials, maybe where to find or how to apply refernce info (like how would you determine draw die depth and radius, and the real exciting things are the topics i haven't thought about yet.
Amazing video I’m for sure going to use this video to explain fillet design to customers. Seams that I have this conversation with customers to often and they never seam to really understand what I’m talking about.
Awesome video. I got this talk from a lead machinist at my first job, very valuable info for anyone in a design or mfg position
Outstanding explanation. Low jargon, high practical information.
I would add, sharp inside corners on large parts like the inside of an L shaped part, if you can just throw a "Allowable radius" callout in the corner, that way it can be made during profiling, and doesn't need to be floor machined from a different orientation
This is a fantastic video - I do mechanical engineering, and while I knew some of these, several of your points here I had never considered before - particularly the 'sharp corner' on the bottom of the pocket being a pain. Thank you so much for sharing your insights! I would be keen to hear your thoughts on heat treating as well in a future video!
I know a decent amount about making things in CAD, and admittedly my manufacturing expertise is limited to 3D printing, but these are some very important considerations to understand that I will definitely think about when I start moving into working with machine shops for metal.
On the other hand for waterjet/lasercut parts rounds on all the edges shortens the cut time and makes it cheaper. Design for manufacture is such an underrated skill people need excellent work!
Just started school for Mechanical Engineering. You popped up randomly in my feed, but I am taking notes
Very good video. I'm learning as machine design engineer, but I spent a little time with CNCs and regular mills/lathes, but even so I wouldn't take all of this into consideration (simply because I haven't use every tool mentioned here). It is probably EVEN MORE useful for people who don't have experience on machining. Such things should be taught in depth for every engineer who's likely to design anything, but I mostly see it taught to people who specialize in manufacturing.
Thanks for this. Any information that leads to smoother interactions between designers and vendors is a net positive for the world.
I'd love to watch similar ones on heat treats, coatings and welding considerations.
I've been sharing your videos with my coworkers in the design department and they are loving them. You help break down the manufacturing process so we'll for the is such digestible bites. This video is going straight into the teams chat for the to watch as required material on Monday.
This is a really helpful video, especially for a beginner toolmakers or fourth year now thank you for your time to make the video
Great video man, this taught me similarly to the whole summer I spent working in machine shop as your explanations were all complete.
Superb!! Thank you so much for this crtical information. This will be mandatory viewing for the design engineers I work with. Cheers again.
In the 3D printing world, filets and bevels are your best friend for making parts fit and shaving off a bit of material use at not cost.
I have lots of machining experience from working as a die maker in my first job out of school. That experience stuck with me so much that when I’m designing a part at work now, my design tree always starts with a block of stock and gets carved out in operations like I’m machining it in CAD. I rarely get calls from the machinist asking to clarify anything.
Such a great video, having the clear examples of so many corner types in 3D, plus the toolpaths, is a fantastic way to teach these ideas. For sure this is getting bookmarked and shared with every junior designer I work with!
I would like to learn more about heat treating. Also I (medical device designer) would be interested in the kinds of tolerances you see that cause you headaches. I know you like your fancy inspection setups too so perhaps your least favourite tolerance types to machine and least favourite ones to inspect?
Thanks Adam, that was a great video, with the interactive CAD explanations. Something similar on heat treatment would be great. There isn't a lot of good concise information about on this all in one place. Always appreciate your video content 😊
Just bought a haas mini mill for the garage. Just want to be able to work for myself full time one day! Keep up the good work man.
As a grad engineer, this info is brilliant. I always try to get the shop guys involved in complex designs, but some things they just don't tell you.
Great presentation, Im only a hobby machinist witj a nome built cnc , but use commercial fusion licence and man I love the way you can preview the too path so concisely.
Great video as always Adam! This kind of information so incredibly useful for people just getting started in the industry and we really appreciate you sharing your knowledge. My school did a better job than most teaching design for manufacturability, but still never covered these kinds of details. Keep up the great content Adam!
Great tips. As a maker I love this kind of content. Even though I live in the US, I design everything in metric (as most of the parts interface with other metric parts, such as the current heat-sink for a Raspberry Pi) so those size tips really help. A guide sheet would be most helpful when designing parts.
I admit my cost guide for features are the instant estimators from Protolabs and Xometry. That is an easy way for me to see if a particular feature is worth doing based on how much added cost it has.
Thank you this was very helpful for me going from designing for 3D printing to designing for machining. I just learned from this video at there is a lot to know about the geometry and the physics of machining to be able to design so a part can be made economically. I just bought an old Novakon 145 CNC mill and lucked into a Microkinetics 1236 CNC lathe missing the electronics. Installing Centroid Acorn to replace Mach 3. I have limited experience with milling machines but have owned a metal lathe before. I need to watch more of your videos because at this point I don't know what I don't know about milling machines.
Heat treating video would be much appreciated!
Designers must know what constrains manufacturing processes have. For example 3D printing can do beautiful fillets. But at which orientation will it be optimal? Which additive process will be used? What percentage of the cross section can you expect to actually distribute the load? ...
This is why I think it's important to have a multi-disciplinary CAD-CAM-CAE softvare like Siemens NX or Autodesk Fusion, so that even less experienced engineers can design, validate and properly optimize parts before pissing off manufacturers... XD
I love videos like these culminating many years of experience! Yours are true gems, keep up the good work!
Would love to see more of these sort sorts of machinist perspectives, thank you! Really cool with the visuals.
I only run a CNC router, but this video is really helpful in my trade. It's kind of hard to estimate how long a one off job will take, especially since I usually need to draw it in a CAD program myself. It's always these kind of corners that cause a time suck. Thanks!
I consider myself an experienced design engineer and I definitely learned some things! Thank you for this!
5:48 another thing about machining these internal radii with a direct match sized cutter is the tool path, its taking a very abrupt 90 degree corner as apposed to a smoother path (some controls don't handle the abrupt corners very well and can cause form issues ), the amount of tool pressure and aggressive tool path combined smells like broken endmills.
A heat treat and/or surface treat video would be great. I’d also be interested in a video about the limits of CNC tolerances with catalog tooling. What can the machinist’s setup realistically achieve without being a huge headache?
I am a design engineer for plastics and cast metals. Thanks for sharing the content. I will definitely incorporate these in my designs😊.
Just love all of this. Learning a bit of both design and machining. Got a small mill and shop and Amy trying to start up my own thing and man do I have a lot to learn.
Very helpful. Thanks. I often get the opposite as well. Thin parts that could have the entire perimeter milled out in one go, but the engineers decided all the internal corners need to be dead sharp. So that turns a one set up job into a three set up job, then they complain about it taking too long. Lol. Engineers are a fickle beast.
Thanks Adam. Great content - I watched the stock/workholding video before this, but a holes/fasteners video sounds like a great idea.
This video is ESSENTIAL for all junior mechanical design engineers.
Great video! Keep em coming please as designers and engineers are not taught about these topics.
"Design for manufacturing" (as well as "design to cost") is something many universities fail to teach.
@all the engineers: Talk to the guys on the shopfloor! Ask them how to optimize your part for manufacturing.
@all the machinists: Talk to the designers. Most of them don't want to make your day harder, they just don't know (although they should actually know) what they are doing
Very helpful to put out, thanks Adam! Yes, the heat treating video sounds like a great topic.
design and machining is like double edged sword, both mechanic and designer edge themselves until someone come with right solution
I am so glad you finally got a mic!
When you're talking about the pocket with equal floor and corner raii, you can get away with using a bull endmill. Try a floor pocket with the bottom of the radius selected as the profile and use a negative stock to leave equal to the tip rad on the endmill. Then constant step up ramp the floor rad. Depending on pocket tolerance you usually don't have to even do a wall finish profile, the ramp up surfacing pass will take care of the floor rad and the walls. If you do need the tolerance or spring passes or whatever, run a profile with the top edge of the floor rad selected and a negative axial stock to leave equal to the tip rad. It does for sure take more time to surface the floor rad, but it keeps it all to one single tool.
Super helpful, Adam! I'd love to know more about how to think through pre/post machining on heat treated parts.
Another brilliant quality video. Looking forward to the heat treatment edition.
Thank you for putting this video out. I love the explanation. This is the sort of knowledge that is hard to come by except by experience.
For additive manufacturing (3D printing) fillets and chamfers are amazing, have no added cost and add tons of structural support
Very nice video! Just wanted to say that if you zero your radius cutter and touch off to the top of the radius, you can just mill at relative z zero. That way you don't end up going too deep by guessing how long the pilot/web is.
Hi Adam. Great video as always. If your looking for an idea for your next video, how about a video on blending toolpaths from different tools. You mentioned it here but I would love to hear you go into the weeds on the subject.
Thanks!
As a home hobbyist I found this very educational discussion ❤
Never thought about it as I come from the 3D printing world, but it's good to know. From a purely aesthetic point of view I think chamfers look better, anyway, and it sounds like that's not a huge issue for external chamfers, but you'll never get a tool with a sharp corner so I imagine internal corners are still a problem to think about.
dude!! +1million from a machinist!!! I can assure you that there is nothing worse than a long deep pocket with equal fillets on the floors. so much more work to get the floor flat because you have surface the corner floors. not a easy check box in cam, you have to create that on a part by part basis. and to make it look good you have to know some tricks to keep it from draggin the wall or chattering in the corners. id say overall takes at least 5x longer than floor with 1/3 or less radius than the walls have.
Very interesting watching. Just getting started with CAD, nice to learn how to make parts that can actually be made. :)
As a mechanical designer I often need to put some kind of corner treatment to make the model look good for the client. Since I do hobby machining I have an idea of what is easy and what is hard so I can avoid the really nasty stuff. Often times I will take a screenshot and go talk to the programer and ask what they want me to put so it's easy for them. Other times I put notes on the drawing or put low tolerances to indicate "I don't care about this other than cosmetics" On the other hand I will make a note "must fit with part XXX"
A lot of time invested in this video, thanks for sharing it was informative. Charles
I would also like to add that designers should keep fillets standardized as much as possible. When it is just for cosmetic effect, there is no need to have four different radii that require 4 different corner mills or slow HSM milling with a ball mill.
Very informative and wonderfully presented, I’ll be sharing with my design team. I’d also look forward to a similar discussion on heat treating.
As always, learned a ton. I would be very interested in a video talking about pre and post HT . Thanks for sharing and take care.
Brilliantly articulated. A must watch for MEs