Understanding GD&T

Geometric dimensioning and tolerancing (GD&T) complements traditional dimensional tolerancing by letting you control 14 different geometric characteristics. It applies tolerances to the form of features, instead of just to their dimensions.

This videos covers the different geometric characteristics and other key aspects of GD&T including datums, material modifiers (MMC, LMC and RFS), the Envelope Principle (also called GD&T Rule #1), and the Independency Principle.

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This will allow me to create more high quality videos covering a range of engineering topics.

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The Efficient Engineer is a channel aimed at mechanical and civil engineers. The mission is to simplify engineering concepts, one video at a time!

[SoumilSahu]

You're doing something invaluable for mechanical engineers like myself and those who take up this field in the future. There is very little content of this quality that's freely available. Thank you for your hard work.

[IFearlessINinja]

I have a bachelors in mechanical engineering and this by far the best lesson I've ever had in GD&T. You are making a real difference to the next generation of engineers

[abdullahahmed]

Iam a Mechanical Engineer and I actually cannot believe that this kind of material is free to watch online with this level of graphics and understanding, for real, you and animagraffs are astonishing, to say the least, thank you for all of this.

[Yred]

I know you probably won't ever read this, but you don't understand how massively grateful and happy I am that I found this channel. I genuinely, no joke, don't think I could do Mechanical Engineering at university if it wasn't for this channel and I just want to thank you for everything you've done and everything you continue to do. You will never understand how appreciated you are and I have told and will continue to tell fellow engineering students how awesome and fun you can make engineering to learn compared to the lecturers I'm stuck with. Thank you so much.

[davidcooper]

I'm an ME and have taken a few expensive classes for GD&T. This is the best overview I've seen. Love your channel.

[KoulourakiaAndCoffee]

15 years in precision machining and working with customers on NPI and DFM, and this is the most concise and clear video I have seen on GD&T...This deserves an award.

[ande]

This is, without a doubt, the best educational and well-made video I have ever seen about GD&T! I have been studying Mechanical Engineering for many years now and always had a hard time wrapping my head around some of these concepts still, the way you lay it out in the video is super intuitive! You also have absolutely fantastic animations, they are so clear, and precise and show accurately what is needed to get the point across. This is absolutely invaluable to anyone starting out with this! Thank you so much for all the time and effort you put into this!

[Robert]

This must be one of the best videos explaining GD&T. I started my career on a drafting board and then moved our company onto CAD in the late 80s' and it was a long time before ANSI Y14.5 creeped in and was finally adapted on new designs. We still had a long road a head to train everyone down stream on what these funny looking symbols meant. If we had something like this video way back then it would have been incredibly powerful. Well done. Absolutely love the clarity of the details and colors used to illustrate, the pace and smoothness of the presentation is excellent.

[zackzaghria]

you did in 30 minutes what my professor was trying to do in 7 lectures. Amazing work

[Kelvin_Foo]

This is one of the clearest description of GD&T I've seen. Explains tolerance zones and geometry control tools pretty well. When trying to explain these to new engineers, I tend to use various shapes of pasta, or GD & spaghetti.

Every time I saw a drawing with circularity or concentricity, it was because the part designer really wanted position instead. In any case, I heard the concentricity tool has been removed from the 2018 update of Y14.5.

[frankpower]

This video is an absolute masterclass about GD&T, I've never had anyone cover the topic in such a clear and concise way. The graphics are simply astounding and the overall quality of this video goes beyond professional.

This content is gold and this channel deserves huge success for its hard work and ingenuity.

[mcsquared]

It is unbelievable how succinct and learnable your videos are. I honestly learned and understood more in 2 of your GD& T videos than from multiple semesters in college.

[danishshafiq]

Definitely high quality work. Been watching videos and online course on GD&T and I can say that this is one of the best explanations I've ever seen. The animations make it very very clear and easy to grab the concept. Keep it up man.

[varunm]

you have just summarized everything in 1 video that took me about 2 months to learn repeatedly to understand when i started my carrier 9 years ago ...
great work !!

[kalpitkatpara]

This is absolutely marvelous!! I cant thank you enough for making these videos. These is the best channel on Youtube providing quality content to engineers.

[xDanossx]

This video is insanely high quality.
Learned more about GD&T from this video than while getting my bachelors in mechanical engineering

[zowiehillebrandt]

Your channel is amazing, the videos are visually stunning, and you cover so much info clearly in such a short amount of time without it being overwhelming. Thanks so much for making these!

[alfiehawes]

I’m an apprentice engineer, just coming up on finishing my first year at the company I’m working for, and the other day a guy who works in design (a CAD expert) was helping me with some simple tolerancing, and said “you wait until you have to learn geometric tolerancing.” When I see him next, I don’t doubt I’ll be able to have a decent conversation with him about it, and this video has, at the absolute least, given me a massive step up on the other apprentices when it comes to CAD. Thanks man

[mikearisbrocken]

Where was this video 5 years ago?! This was easier to understand than the courses provided by my job!

[olarubogdan]

You sir are a blessing to us mechanical engineers that are fresh out of the uni. I love seeing your videos and remembering the exact things i did in those classes (Finite element and many other things)