GD&T - Selecting Datum Features

This video shows how to choose datum features with functional GD&T applications. Functional datum features benefit design, manufacturing, and inspection. Non-functional datum features cause stack ups of profile and position tolerance.

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[dylanruskin]

this video is great. After endlessly scouring the internet to try and figure out what datums are i finally found someone who can explain things in a way i can understand.

[Random-smgi]

Hey man, I’ve been watching your Youtube videos for free. You are the reason I learn this stuff. With my first proper salary, I’m gonna buy your course just to thank you. These lectures are banger. Thanks boss

[MohamedAmarch]

Hi,

This is the first time I discovered your channel.

Thanks a lot for your valuable work.

[alirezagharib]

Very effective and straightforward, Thanks for your work!

[akshaymasali]

I have been watching your videos. Great stuff, please continue making videos like this.

[tomsko]

9:28 - To help you decide where the C-Datum should be, you need to decide what you want to measure on your gauge. Earlier on, besides worrying about constraining the part and how it gets assembled (two very important details), also think about how the part will be measured on the gauge and what you want to measure. Choosing the pin hole is a good idea, it allows you to more easily measure th latching surface of the bracket.

[Shakila-wj]

Thanks, many videos on gd&t was there teaches theory, thing that set you apart is realtime examples. Great work

[crazyingenieur]

On Seat Latch Bracket Application (9:50), if the hole (3.0 - 3.2) is the datum feature C, then the DRF should have been | A | B | C > |, where `>` represents the translation modifier. Unfortunately, this detail has been missed.

Another alternative DRF would be (maybe more realistic): | A Ⓜ | B Ⓜ | C Ⓜ |

[axeonhand]

Nice explanation.. Expecting more videos on selecting datums

[dineshnadgauda]

Wow that's I am looking for.... Thank you so much

[saurabhgaikwad]

Excellent video, i understand the complex parts very easily ❤

[ronconovoa]

this is great information thank you for that

[jeff]

Quick mention...the base part is missing B datum in the secondary prequalifier callout. Terrific vid btw..my favorite for detaling out a functional alignment scheme, and how to bring up VC and boundary conditions (fastener size).

[sem]

Seems like the recommendation in this video is to always constrain 6 degrees of
freedom. But what if we constrain less and then rely on simultaneous requirements to take care of mutual location and orientation between those features considered as followers? For example in the seat latch bracket case, the hole used as datum feature C is just where the handle for operating that mechanism mounts. I wouldn't really say the handle is imposing a constraint on this part in assembly. So I would think of using only A and B, and then the profile tolerances on other important features such as the face where the square holes are and a position tolerance on that hole, all referencing A and B in this order, would form a simultaneous requitement that would mutually control them. That way only 5 degrees of freedom would be constrained and 2 datum references used, but still everything would be fully defined. Are there any cons to doing it that way?

[maherdaibes]

at 4:19 can someone explain to me howe is one one a hole and one a slot?
because they both look the same to me

[nicholasminehan]

In the sheet metal part example, when you use an all surfaces profile tolerance to datum a b and c with unspecified dimensions basic in addition to a plus/minus thickness tolerance, which side of the surface is controlled position and orientation by the profile tolerance since there is now a thickness tolerance involved?

[domi]

5:30 Do the center plane of slot C must go thru circle B?

[Abhisekh-xk]

Do all holes have to be located using one of the datums or can there be basic dimensions locating hole to hole distances?

[冯孝伟]

Do we have any solutions to avoid the secondary and tertiary datums created by threaded holes when it has to (bolted with threaded holes and against a flat surface which is datum A )? It's reaaly hard to get a constant testing value when threaded holes marked as datum B & C on the drawing?

[palleturu_memories]

can you explain me where 0, 0 from on that seat bracket?..how 3- DRF planes will come perpendicular to each other
?