GD&T Lesson 2: Form Tolerances

This is the second video in a series of GD&T lessons.

I cover Flatness, Straightness, Circularity and Cylindricity.

At minute 10:50 there is a mistake, the gage would be 1.05, not 1.06 like I say in the video.

00:00 Introduction
01:10 Straightness
08:14 Flatness
10:54 Circularity
13:44 Cylindricity

[HaloWolf]

I appreciate the free education Mr Odell. This will enable me to be prepared for a up and coming job interview. People like you make the world a better place.

[bassmechanic]

Thank you kindly for these lessons. I just became a machinist after 46 years as a mechanic. You are a God send as these lessons are wonderful.

[theunfrailhale]

Gotta say, your content is top notch. Thanks for all this work!

[rizalardiansyah]

Just leaving a mandatory comment for the algorithm. Thank you for sharing this course with us!

[stevedeprospo]

Thanks, I'm starting a new job tomorrow at an aerospace company and this helped me brush up on my gd&t

[sourabhbhalke]

Better than some paid content. I'm surprised! Thank You!🥰

[rocketscience]

Great Video. The pros and cons of each GD&T feature were very well explained. I have been a chief engineer in the gas turbine industry for over 15 years, and I haven't met any two engineers or machinists that can look at a drawing and interpret it the same way.

[irfanulbhuiyan]

at 7:19 it takes up 1.06 and violate MMC? should it be 1.05 instead?

[chemingwu]

At the timestamp of 10:50, you mentioned that the gauge to check the flatness tolerance applied to feature of size is 1.06. I am wondering if the functional gauge size should be 1.05 (1.04 is the MMC + the flatness tolerance of .01)

[yogabrindha]

You saved my life... Thank you so much for giving us elaborate explanation❤️❤️❤️

[shadab]

Mr. Odell please make more videos on cmm, I am a quality engineer and it will help me a lot to make programs for different components of engine🤗

[susanthompson]

can someone explain again around the 2:29minute mark why it is 1.08? If I understand video 1 and I do the tolerances that at 1.00 size dimension there is .08 tolerance and we are selecting that because the dimension is 1.00? Confused but trying hard to understand. And we chose that 1.00 dimension because there was no MMC indicated correct?

[jeffersonsong]

Pls help clarify. At 6:41 shouldn’t it have .08 straightness tolerance at 1.00 diameter because it’s .04 mmc plus the .04 difference?

[studdruppo]

You mentioned watching another video at the 7:25 mark about MMC boundary and straightness tolerance but I don't see the link. Could you please list it.

[deepakpatel]

Hi Mr Odell, you mentioned the gauge size should be 1.06 inches to check the flatness for the example with derieved median plane. I think it should be 1.05 In : 0.04 size and .01 flatness. Am I correct? I am referring @10:45 sec of your video.

[AlfraRed]

Why can it take up 1.06, not 1.05. I thought the MMC is 1.04" dia + .01" of bending? Can anyone explain please?

[elcidcampeador]

You may want to move the chapter marker back to 7:40 for flatness

[MattRoberts-tg]

How do circularity and cylindricity form tolerances compare to runout and total runout?

[zamree]

Hi,

Almost all of the time, the datums specified in any component drawing are the features available inside that drawing...A...B...C...you can find them inside the drawing itself. I will call them localized or local datum...it is part of the component.

Now what if i were to use centralized datums...for example...i took one point with coordinate of xyz on a car as my use that point to control all applicable symbols in all related car component drawings. The side mirror, the tail gate, even the plastic panel covering...all refer back to my origin (xyz).

Is that allowable? And is that not more hassle for manufacturing and assembly pov?

Thx.

Now...what if

[cvdh]

For a conical shape, would you use circularity and straightness? Also, would it be easier to gauge calling out circularity and straightness rather then cylindricity? Or do they use the method to measure both? Anyway, love your videos.