How to Design Parts for CNC Machining

[@adrianhood4368]

As a newly graduated mechanical engineer, thanks for teaching what we actually wanted to learn!

[@gokiburi-chan4255]

This sht was never taught in my school lmao,

[@JB-dv7ew]

@@gokiburi-chan4255 Bro nothing was taught at my school. Not how to design for assembly, design for CNC or sheet metal, or detail drawings properly, etc. I can solve quadratic equations and find the Jacobian of a matrix though.

[@jay89boy]

@@JB-dv7ew too acurate :D

[@howardjones543]

This has to be one of the densest and most useful 10 minute videos on KZbin! Thanks very much.

[@swamppifi6186]

I work as a CNC programmer and the amount of times I get a cad models that people poorly design, and then expect to be able to machine , is just mind blowing. I often have to go back and make some suggestion on how to change the design to allow for easier machine. Thank you for this video...

[@JB-dv7ew]

Yup and you'll keep having to do it because engineering schools don't teach this shit and I have no idea why. It's the reason why I'm here as a mech engineer.

[@JayP0205]

I’m one of those fools and got zero quotes back because of a design that even a 5 axis couldn’t build lol. This video saved me a ton of unanswered questions

[@marc_frank]

​@@JayP0205 not even a message?

[@nenadratic6319]

The key of good design is a cooperative work between designer and manufacturer . Some time a simple change in design can make a production a lot easier and chipper . Like designer , you do not have any limits in CAD modeling , but when you start think about manufacturing , that is a totally different world . Good design , think a make a good functional part , but for a reasonable price , because if it is too expensive , who will buy that . I'm the old school , finished my carrier like CNC engineer , but start to work like design engineer . That is the only win-win combination .

[@stefnirk]

As an engineer, I am amazed at how machinists quietly made my shity parts even when I had no idea what I was doing. Please educate your local engineer since many think a CNC machine is a magic 3d printer.

[@casemerasheed3875]

At this point im just going to comment every time I come back to this video, to reassure my self before I submit a design to be fabricated. This is an extremely informative video👍🏾

[@shawarebs]

As a mechanical Engineer, this is one of the most helpful videos I've ever seen. I'd love for another video similar, but with more advanced topics (flatness, perpendicularity tolerances wrt features done on the same vs multiple setups ... etc). Great content!!

[@chevycamaro-rp6tr]

what a helpful video! dont mind all the people commenting on your voice, i found it very easy to understand every word which is important in such a informationally dense video.

[@BenTheMagnifice]

Surprisingly great video to find on KZbin! Packed with accurate information and no fluff. Please make more!

[@lephtovermeet]

Some good basic advice that I wish was still standard in many engineering degrees. That being said some of this is quite dated. For instance flat bottom holes are extremely common with helical milling, in fact that's the go to for many machinists, albeit the length and depth requirements still apply. Similar critique for thread tapping. It's not super common to use taps on a CNC. There's too many thread types and type styles, plus the break easily. If you're tapping on a mill, you're likely thread milling, which does have diameter requirements, but again is basically the go-to for many of not most machinists. Also chip clearing taps are super common. Also, t-slot cutting and undercutting are again super common, but you do have to work within the limits of your tools and common sense. Also never just put break edge. Someone is just going to hit it with a file after it comes off the mill. I've seen some real disasters. Finally, much of the increased costs when quoting with autoquoters is fairly arbitrary - they charge more because they can and that's what their algos and data have optimized for - especially xometry, they're a huge offender with really unreliable quality. They're actually just a re-sourcer, so you never know what you're going to get. If you are machining in house what drives up cost is having to buy more tools and holders for those tools, and added setups. If your CNC has a tool changer, it's common to leave 2 or 3 slots open to change in specific tools for the job. It usually adds very little extra time or cost to fabricating. But nice vid, thank you.

[@casemerasheed3875]

Ima a self taught product engineer. Its amazing how many time i come back to this video, when designing parts. It literally answers 90% of what ever design flaws im making.👍🏾👍🏾👍🏾👍🏾👍🏾👍🏾👍🏾👍🏾👍🏾

[@TiMechOfficial]

I graduated as a industrial machinist in 2018 in Germany and changed my skill field to cnc machining in 2019 (DMG 50 1. Generation & 3. Generation + DMU600e + DMU800E) with self taught experience in fusion360/solidworks/inventor i have 4 years experience (3 years of learning not included) and THIS VIDEO IS ONE OF THE BEST DETAILED Tutorial ive seen in this niche! WELL DONE! i would add 1 thing: ALWAYS GO FROM STABLE FORM TO INSTABLE FORM (sorry for bad english -.-), so your part wont fly away ^^

[@russwizinsky8041]

What a fantastic video. As a machinist I thank you and will be forwarding it to my design team. Very much appreciated!!!

[@gokiburi-chan4255]

Trying to learn this so I won’t torture the manufacturing team in the future 😂

[@ChrisTrunek]

Watching this ten minute video just helped me save a lot of money. Excellent clear and simple information. Subscribed!

[@NathMich9]

if you know all about this you are in the 1 best pourcent of designer and you make cnc maschinist so happy and make his work easier. thk for this video from a french maschinist

[@joemac-q4x]

I have spent the last 2 weeks trying to get to know about cnc designing and work and I unquestionably learned much more in your 10minute video than over the whole 2 weeks, !thank you!

[@StaleCookies]

As someone who is designing milled parts for product design this video is invaluable. Subbed👏

[@jensonhartmann3630]

These are great rules of thumb, a great foundation. well done!

[@Omsip123]

2:47 shouldn't the radius be LARGER than a third of height, like you show a few seconds later?

[@captainmurphy4720]

WHAT A TON OF GREAT INFO IN 11 MINUTES. THANK YOU SIR.

[@whynotanyting]

I've been meandering on KZbin hoping a video like this exists, and it's here!

[@someotherdude]

This video is extremely effective and straight to the point. Well done!

[@thomasprice5728]

Fantastic video! I'm a design engineer with a bit of machining experience and this is an incredibly concise, comprehensive and accurate view on designing for milling. I especially liked the deflection graphic and math. Looking forward to seeing more videos my dude

[@runmycode4940]

Great video, i wish that all new part designers watch and learn from it

[@briandrake6881]

Love your work, Adam. Thanks for sharing.

[@haavard1989]

I used to make parts for a company where some of the designers were former cnc-operators. No really insane parts, no tolerances were smaller than necessary and the RA was often just general.

[@tri5431]

Very helpful video, thank you ! You're saving a lot of headaches for many machinists out there. The only comment I have would be the extreme vocal fry. My Bose speakers don't have a bass/treble adjustment, so it's very difficult to make out the speech.

[@RadicDotkey]

You don't need to add forced vocal fry to sound pro. In some parts you sound normal and those are way easier on the ears.

[@47EZ_DRIVER]

yeah Adam should re-record this with his normal voice. I turned on captions because i cannot stand the audio

[@pvtimberfaller]

It’s too creepy to listen to.

[@EYes-zy6my]

“NU VOIS” is fried…

[@DarksChannel567]

Literally said exactly what I was thinking

[@benjaminmcintosh857]

Pretty sure old mate just had a sore throat guys

[@Frrk]

Absolutely great video man. Very clear to understand. I'll forward this to teachers!

[@steelcannibal]

Dude! Fantastic video breakdown! If only more engineers understood this 🥴😵‍💫

[@easylivinglife6284]

As a logistics manager, I appreciate you adding the stock size to part size comment... however, I often find that CNC programmers have a unique mind, and may prefer to use larger or smaller stock if it means holding a fixture a certain way, making more than one part pert blank, or decreasing machining cycle time. For example, say you have a part thats 2'' thic by 2'' wide. A programmer may request a blank thats 4.5'' thick by 2'' wide, cut into blanks for length and machine two parts from said blank. While technically increasing cycle time, it actually reduces it the total time per part- less time loading and unloading the fixture, and less time cutting the material. And think about it, would you rather have 200 12foot bars strew about because you have to mass manufacture some small dinky part? No! You want a few decently sized bars that the CNC program can make the most use out of.

[@Unl0gic]

Thanks for a very informative video without any "Cool KZbinr nonsense"

[@everybot-it]

Immensely valuable content! The only suggestion (respectfully): if possible, adding a little more "voice" and less "raspiness" makes listening easier. Like briefly @9:19 ish, there it's perfect!

[@TijmenHatesads]

Imagine uploading a video where the cnc machine itself tells you what it wants. It would save me like a year in education and trail&error.

[@eviebee4]

Whoa. Thanks so much for this video. So much useful information delivered clearly and quickly. Cheers!

[@bikefarmtaiwan1800]

Super informative video . All great stuff to revise and remember . Well done

[@HannahBright-g1l]

It is even easy to understand for me, even though I am not a machinist,I am just a project manager who are working for promoting the cnc machining services in China.

[@james2749]

What about machining draft angles for moulds? are there bits for that?

[@bhekidlamini51]

Do you have pdf content of this video. Excellent!

[@koroshghanbarzadeh1360]

One video to rule them all.

[@satibel]

do note that for threads, you might want to have a larger diameter drilled out on the other side (this can be done on a drill press if it's the only feature) so the screw has some space to go, and that also allows you to specify a single size of fastener, which can be quite a lot of money saved for production (as it's one less part on the assembly line and you can order bigger bulk), and less headache for maintenance. also it allows some wiggle room in fastener size, so if a suppliers offers you a slightly longer screw for cheaper you can switch to this one.

[@ashjo17]

Wow! such simple and cleared explained concepts.

[@brucewilliams6292]

Really well done! Thanks for the video and Merry Christmas.

[@lucmartz]

4:16 interesting point… as a rule of thumb the effective thread that the screw is engaging should at least be 1.5x the diameter of the screw. If you can 2x better. This L

[@kateiry4719]

The crispy deep fry voice is too distracting 😂

[@dGAMER-tr3hw]

Explaining ❌ Scaring+explaining ✅ Best explaining but my little brother scared 😂

[@noahlynaugh5025]

Does this apply to 3D surfaced tools for injection molding? Or what about when Apple mills something like a macbook? Does that have radius top and bottom edges? How do they do that process efficiently?

[@ItsJustWolff]

As a machinist, this is great.

[@free_spirit1]

Excellent! I wish there was a similar video for designing for turning!

[@robwgeorge]

Fantastic presentation and explanations. Thank you.

[@pentikimahougami8348]

2:10 For pedants, the words diameter and length are switched for this timestamp.

[@popinmo]

is it normal for some of this to sort of be intuition or feeling? like as for the drilling edges thing

[@lucmartz]

1:59 where is the force estimation coming from? I guess it depends on the machine but the machine never apply 100% of the capacity in all the cases.

[@dexterc7050]

Very clear and excellent video!

[@ekingorgu]

Adam this is an amazing video. Please make more videos like this. Subscribed.

[@PettiMusicStudios]

This is a fantastic video. Thank you

[@kdprocnc]

Tihis really help me a lot,thanks for sharing~

[@MjuMeli]

God damn this is a rare pull of a video.

[@casemerasheed3875]

Truly Great and informative video 👍🏾👍🏾

[@sayfmateen5754]

Thank you for the info. Waiting for more on turning and fixtures..

[@crisrose9707]

Its interesting to see how CNC machined parts are ideally designed completely differently to 3d printed or injection moulded parts, often times being the exact opposite!

[@financialchimes4546]

@6:29 I've heard you should avoid bosses because it's more cost-efficient to mill a surface flat than to mill several different small bosses within the same flatness as the edges on the bosses leads to reduced tool life. @7:15 I've been taught that fillets at the floor of a pocket can reduce costs if you use the same radius as standard corner radius end mills because the sharp edge on flat end mills breaks and wears a lot easier. What are your thoughts on this?

[@typhoys]

From my experience it is true that bosses are expensive but it is easier and cheaper to achieve flatness for a smaller area

[@EricBrummer]

If the bottom of your pocket has no impact to your design, you can always call out in the drawing something like "R0.5 MAX, sharp corner allowed." Then the machinist can choose based on what they have and what they think is easiest. On some materials, using a bull nose end mill can be a major tool life saver. As for bosses and flatness you can really get in the weeds on details. Size and thickness of a part matter a lot. Holding flatness in 2 small spots on either end of or across the whole surface of a partrhats 4ft long is going to be difficult. Same thing with thin stuff that is being warped clamped in the vise. Also depending on the amount of material removal the part will change shape as you relieve stress in the material and/or reduce the rigidity by making it thinner while clapped. If the part is smaller, like a fits within the visse, then you can rely on the accuracy of the machine heavily and get a decent flat surface especially if using a fly cutter to cut with a single point. Having discontinuous cuts (tooth cutting then not touching then cutting) is bad for tool life especially carbide but with the bosses shown you might not even have that issue. Face the whole thing first, then relieve around the feet. Although on a small part there's probably no reason to have feet. Much larger stuff the feet help although for anything requiring really tight flatness I'm probably existing grinding anyways in which case I don't think the feet have a major negative impact (and save time on grinding) but I'm far less knowledgeable on grinding.

[@angelalexandrov2831]

Great video - thanks! If you make something similar for lathe parts it will be very useful.

[@AdamBender]

Good suggestion! I will add it to my list

[@foxzerox1000]

At one point you say to always add fillets to the exterior, but then say to never have fillets on the top part instead gave a champher but if they are going on the out side anyway wouldn't thst make any given side the "top" for that operation? Like how do I know which to use?

[@fake08]

such a good, informative video

[@jesseskellington9427]

On a CnC milling machine Do you have a video on how you can take square stock and turn into brown stock? I find a lot about ladies doing this but not on a mill. I have 1 in by 1 in square stock that and what one in 1 in down round... Do you have a video on this operation? :-)

[@cancerix1700]

2:40 should't it say R > 1/3 H ?

[@patrikdahlberg1825]

Thanks bud. Some great advice here! :D

[@GMBurov]

Thank you very much for your advice! 😌

[@pardo94]

very interesting sr!! thank you :)

[@mihailazar2487]

But floor fillets can be perfectly reasonably machined with a bullnose endmill, which is what they usually use anyway for roughing. So having sharp floor corners actually requires an extra finishing operation with a flat endmill

[@GameBacardi]

Good video to think about these.

[@theotherhive]

nice video :D very helpful

[@chrischalabi]

Great stuff, but definitely try to avoid the monotone. Also you should rename this video to CNC Milling and also make a video for turned parts.

[@AdamBender]

Thanks for the feedback, I'll definitely work on the voiceover in future videos. Lathe video is on the list!!

[@TheeAthis]

Great basic information!

[@asheshshrestha]

It is a really great content. Keep it up!

[@etchmfg]

Great info! I had a hard time hearing you though, perhaps its your microphone.

[@LongMai-h5h]

Hi Adam, Thank you for the videos, it helps me a lots. I have a question. In case of internal fillet, is it harder if we machine an internal chamfer instead?

[@drew79s]

Good stuff... The floor radius information isn't exactly right though. Using a small floor radius can work really well if you're using a radius endmill, as a 10-12mm endmill will have about a 1mm corner radius, this means that you can go for a fine floor radius with a wide vertical corner radius. Additionally, the undercut feature you've drawn isn't possible to machine, but there are t slot cutters and dove tail that do a nice job of particular feature types, so as long as you're standardising on those feature types undercut isn't a problem at all.

[@AdamBender]

Good feedback Drew! Yeah bull nose end mills with small corner radius can be great for harder to machine materials like stainless, or lowering stress concentration. Agreed on my undercut drawing, I got a bit lazy with that one, but I was hoping it would get the idea across. T slots and dovetails are two exceptions for undercutting when done correctly. Thanks for the input and watching the video!

[@martinjensen4714]

Are these "design rules" covered in the mentioned books? If so, I guess they are a must read for any engineers like myself!

[@ambroseliu6207]

Very helpful to mechanical engineer

[@mouhaahaahaa]

nice video but are you an extremly heavy smoker or something

[@Drokkstar_]

I thought his batteries were running out.

[@pizzaspider]

why don't you buy more subway stocks

[@BlackSmokeDMax]

Those top fillets aren't too terrible if necessary... As long as you pick a radius that is a standard cutter size. Search "corner rounding end mills", and usually the smaller you can live with, the better!

[@ajayjb8727]

Great video , really helpfull, Thank you

[@AlojzyZyrokompas]

What's with the shy growling? Otherwise pretty informative. I wouldn't agree with R being 3 times smaller than H though, in most cases You can successfully make it 6 times smaller without compromising milling precision.

[@iamthebiker]

Great video

[@LibertyWarrior68]

This is good information.

[@enricodesign619]

great video, thank you

[@JinKee]

9:28 interesting - shapes that are impossible for cnc machining are excellent for injection moulding/additive manufacturing.

[@franciscodiaz6290]

You can make those shapes but as the video says it takes a lot of time, some radii we'd machine would require 1/8" ball mills or smaller. Making multiple cavities for blow molds these radii could take an entire day to machine

[@JinKee]

@ and the easy machining to make the external chamfers of a steel injection mould will let you make the complex plastic shape ten times every second.

[@MrKillermeatball]

About to give a presentation on this, was watching videos to see if I'd forgotten anything in my notes... INTERNAL FILLETS SUCK! XD

[@pentikimahougami8348]

Speedymetals is also pretty good about price/selection.

[@sreerajpanayancheril7206]

great video

[@wangqiaozhang4827]

wow, really helpful!

[@lucmartz]

5:40 this is key specially if your machine is not super precise…

[@abhiadsul6538]

Very informative

[@zaccomusic]

nice contents I hope you keep update :)

[@m.berger2370]

Thank you !

[@grateful4068]

found this via Hackaday. Subscribed because of this video. Great work.

[@AdamBender]

Thanks!

[@ranjah76]

Me too!

Excellent, more! 🙂

[@Festivejelly]

Jesus the vocal fry was off the charts until the end!

[@donfite2081]

BRAVO!!!

[@AlJay0032]

Seems you got your axis wrong. CNC mills don't use left handed coordinate systems.

[@AdamBender]

Good catch! looks my labelling got flipped

[@AlJay0032]

@@AdamBender Thanks for this great educational video.