For other videos on engineering and manufacturing subjects: Strength of Materials: th-cam.com/play/PLAXJqmuqGEr7QjsVVyl5jFY6HQTqw6Bfq.html Metal Casting: th-cam.com/play/PLAXJqmuqGEr4wiY6xroSK67CXeTu0Otmk.html Quality: th-cam.com/play/PLAXJqmuqGEr4LQvNzKHGO9l00gEN4gmSP.html Design: th-cam.com/play/PLAXJqmuqGEr706zgRtnwgQiFC5FYLvaTr.html Automation: th-cam.com/play/PLAXJqmuqGEr6O_nQ-n08qmrtNnAUruj3b.html Calculus: th-cam.com/play/PLAXJqmuqGEr7Ayo18H7tknyQAJu1OcoUW.html
Explanation is good. But its 2018 you should always show a live inspection vs alot of taking. Do a live video checking tru pos of that hole instead of talking. Talk less show more.
@@TeW33zy Comment is good. But its 2022 you should always talk with an appropriate attitude vs being condescending. Be more polite instead of commanding. Rude less kind more.
Your videos are excellent. I'm a Canadian Mechatronic Systems Engineering student reviewing GD&T, and you did a much better job in 22 minutes than my profs did in hours. Please continue to make more GD&T videos!
3-2-1 had me scratching my head! I've been so used to CAD doing my constraints, I always assumed that I would never need to specify part orientation. I spent a few minutes confused by the datums but it finally sunk in: A references the back plane, which 3 points don't particularly matter. B References a (single) line along the top of the part, and C is any point along the right side. This opens up a better way to not just describe and manufacture my parts, but also the documentation/use of assembly jigs and part handling, thank you!
Doc, no matter how many tines I watch this same video, I continue to get value from it. Thank you sir, had you would have been my instructor back when I was undergraduate and graduate school I probably would have gotten my PHd.
You are more complete than my professors were 30 years ago. They spent an entire 30 minutes on the subject. I learned most of it on the job. I had to teach this to my daughters because her profs didn't mention it.
i mocked up my resume to get an inspecting job..and it worked...now I'm going into this job not really knowing anything until i watched this..definately needed the 3,2,1, rule
Good Job with the 12-modes of motion or the 6-degrees of freedom...DATUMS are the key to any tooling set-up. Thanks! Thomas J. Vanderloop, Author, Technology Instructor & Manufacturing Contractor, CMfgE & LSME
Even though the 3-2-1 rule is common for establishing a coordinate system, it does not satisfy ASME 14.5 for a DRF. In your example, you would need to use 3 perpendicular planes. Datum A feature would locate on the 3 highest points, Datum B feature would locate against the 2 highest points and Datum C feature would locate against the single highest point on that surface.
Hi, thanks for this video that you have put together. I have a few questions for you regarding it if you don't mind - I know little about machining and my questions might be a bit basic: 1. Why would the basic dimension of 16 not be measured from B, as B would be a sure reference to measure from? Why would basic dimension of 34 not be measured from C, as C would be a sure reference to measure from? 2. What importance in terms of tolerance would 10 play, it doesn't seem to have any mention? The surface that it is measured from might be rough and inaccurate when compared to the other official Datum sides (AB & C). Is it not important as to the position of the hole set (the two holes) in relation to the boundaries of the rectangular block it goes through - maybe that block doesn't need to mate up with an adjacent component accurately, but just for it to be attached using bolts? 3. The slide with the 3-2-1 Rule at time 10:02 for example, shows the Right Hand Rule and the 6-axes of freedom. The axes don't coincide in those diagrams (although I can mentally rotate them and see what's going on)...generally speaking, the z-axis is the vertical axis (elevation view) isn't it - thought I would mention this as I think most machine set ups would be with the z-axis vertical (is this the case in industry standards)? Additionally, I know this might not matter, but do you have a preference to which axis has the 3, which has the 2 and which has the 1 restrictions for movement? 4. Why is the term 'counterpart' used, what does this mean in this context - I would imagine it means equivalent part? 5. At time 14:51 it shows the ABC Datums in the control frame and you mentioned that A-Primary, B-Secondary and C-Tertiary need to go in that order and that set up, so even though, some other arrangement of the stops to hold the part in place on the machine would ensure it does not move and all freedoms of movement have been stopped, why would this order be important? Is it related to axis preference or some other preference? AB&C would all be trued up and equally suitable for datums (or are they not?) - is it to do with their specific machining tolerances? 6. The (2x) indicates the two holes I would expect. 7. To achieve a diameter accuracy of 0.001 for example instead of the 0.06 for the holes, would this mean using a more accurate drill bit/chuck/more expensive machine in practical terms - which would make the manufacturing of the part a lot more expensive? Thanks for your help. Kind regards. David.
WHY are None of the dimensions given in relation to Any Datem?? The "A" has no relevance to the hole position, the "10" is on the far side from the "C" and the "16" is on the far side from the "B". Makes no sense to me.
First thing, that most of the information for that part is left off. I assume that was done to leave only the symbols that the Prof. wanted to focus on. My understanding of how "A" applies to the hole position, is that because the hole is actually 3 dimensional (a cylinder), the axis of the cylinder is to be perpendicular to plane "A". It made no sense to me until I got away from the idea that the view was a 2 dimensional drawing.
Edd is spot on. Terrible example "Professor" shame on you for adding to the confusion of GD&T. The primary "A" datum controls perpendicularity of the holes (cylinders), the "10" and "16" should be located from the datums B & C (or the datums need to be on the opposite sides where the dimensions are located from). it's fine that the "10" is not "Basic" and therefore it would be the drawing block tolerance which would apply not the positional tolerance, but for this basic lesson it probably should have all been basic dimensions located from their respective GD&T datums. It then would have been a worthwhile lesson . In the real world as presented it would force a call to the engineer and drawing change.
Good explanation. The only comment I have is your orthographic projection is 1st angle projection. North America 3rd angle projection is most commonly used.
How come the dimensions do not start from datum planes? They're all from the opposite plane. Don't all dimensions have to originate from or be traceable to datums?
Hi Professor Cummings at minute seven you talk about the 321 rule and you have 3A, 3B, 3C. you seem to refer to them as three datum planes…when actually they are the same datum planes… so why would you call them ABC when they’re all co planer?
First off, I'd like to thank you for making such an informative video! Could you please elaborate on the 3-2-1 rule a bit? Isn't the block still capable of moving along the "+" directions of all of the 3 axes? I mean, fixture 1 stops the block from moving along the "-" direction of the Y axis, but it can still slide in the "+" direction, right?
Amazing why cant you be my professor mines suck do you teach at any cuny schools in ny like the way you teach is so intresting catches my attention and goes straight to the point
Infinity MFG thank you so much we need more professors like you can you do more videos on this topic showing more tolerance and dimensioning and charts and explain tbe signs like for ex the m or L and stuff like that and practice problems would be nice
Zaph Kiel hi, in cnc machining and using a cmm the z-axis is the translation of the spindle. X and Y are relative to that. This applies to vertical and horizontal equipment.
Good basic knowledge but can you please provide some knowledge regarding datums in relation to net pads resting, 4 way and 2 way for stamping perspectives
Thanks for watching! I plan on putting up the full class on my own page. Make sure to keep watching for it. www.theengineersreference.com/videos-2/engineering-drawings/
Please forgive me, but, since when is the "Z" axis not vertical, the "Y" out and in as viewed by the operator and "X" not right and left as viewed by the operator?
such a awesome explanation .. really I learned something what I need. But i have a doubt like . How profile tolerance get effect by MMC ?? I have seen in some blue prints asking profile with MMC !! seeking for your answer.
Hi Raghu, Thanks for watching and commenting. There are two modifiers that use the same symbol, 'Maximum Material Condition' and 'Maximum Material Boundary'; they use the symbol of an upper case 'M' in a circle. A profile tolerance is subject to MMB, this means that a surface is being treated as a boundary or datum feature (secondary or tertiary). This gives information to the engineer on how to design the gauge (datum simulator) so that the maximum material is accounted for. You can get more information on this from "Ultimate GD&T Pocket Guide" - 2nd edition on page 38.
Not a dumb question at all. Inches VS metric can usually be found in the title blocks of a drawings. See this video for help: th-cam.com/video/M8fAF0xMxBs/w-d-xo.html
a technician once told me if the plan doesn’t specify, that metric units rarely have more than one decimal place and that english measurements usually have 2 or more decimal places
To all the engineers out there. Please for the love of god, try to make the datum point something that's intuitive and easy to find with conventional calipers. Pleqse please please please, whatever you do, do not locate your datum off the theoretical center of a hole or radius Sincerely: a contract manufacturer
Very clear and informative. Would you suggest any textbook(s) for GD&T (whether one of the 3 in amazon's top 30 in Drafting and Mechanical Drawing or some other)?
Why is the Z-axis not vertical to the horizontal plane?? In segment 9:09 I see Y-axis vertical to the horizontal plane. Is this a North American thing? Isn't Z-axis always perpendicular to the horizontal plane? I had a tough time getting my point across to an engineer in Ontario, Canada. I could make out he came from the Auto-CAD world (2D) where X-axis and Y-axis goes along the Length and Height of the monitor screen and Z-axis comes towards you - the operator. This is incorrect per me. There has to be some standard. To me Z-axis always directed towards the sky.
The orientation of the z-axis isn't tied to 'horizontal' or 'vertical' per-se. Typically, X-Y-Z and the left hand rule are centered on the concept of following the device (tool spindle, inspection probe, etc) That is what dictates the Z-axis, the X and Y axis depict travel relative to that. This is why you can have machines that are 'horizontal' and 'vertical', they are telling you the orientation of the spindle.
the teacher mentions Right hand rule in video, but L H rule in reply? the way I learned R H rule is simple, cross the X towards the Y and the Z will unscrew out of the plane. So that way you can place the XY plane at any orientation, and you expect Z to unscrew out of it. Take a look at a CAD screen and watch the results as spelled out here!
The 3-2-1 rule doesn't restrict movement in all directions. No one can machine the part with those constraints only. The worst part of your example is that you have three datums and two basic dimensions that are from feature planes that are NOT the datums. You have no idea where the holes are located with respect to the datums because you are lacking the width and length of the part. If you are picking datums, you should probably use them for your dimensions, especially basic dimensions. Part of the problem with every GD&T lecture that I've attended or listened to is the fact that the prints are not complete. I want to see how you put EVERY dimension on the print for the people in the shop who must make this part. If the basic dimensions for the hole must be from a side that is not a datum, should the width and length of the part be basic as well, so that basic dimensions to the hole from the datum are ALL basic? Show me the print as it needs to be, not partials. Even Lowell Foster, arguably the father of GD&T, did this, and it drives me crazy. Datums on a post look stupid and take up valuable print space unnecessarily. I specify 14.5-1982 in my title block so I don't have to see the concessions made to the ISO community by the GD&T committee on my prints. What purpose does the post serve? Further, I would like to know the differences between 14.5-1982 and 14.5-2009. As far as I can tell, they are the same. Symmetry went away in 1992 but came back - I don't know exactly when. On the other hand, unlike the guy who said he is "dumber for watching this," even though I do not agree with everything, I did learn something from the video. I didn't notice the "snap, crackle and pop" of the sound.
Hi Teacher where I can get this certificate for mechanical measurement and inspection even I have been training and worked in previous company but like to get this certificate sincerely student
Basic dimensions to the 2X hole features must originate from the datum features. Not an option, major fail for an instructor to present this. Explanation of the 3,2,1 part indexing / degrees of freedom indicates datum target simulation, this is misleading. The drawing requires planar datum simulation.
For other videos on engineering and manufacturing subjects:
Strength of Materials: th-cam.com/play/PLAXJqmuqGEr7QjsVVyl5jFY6HQTqw6Bfq.html
Metal Casting: th-cam.com/play/PLAXJqmuqGEr4wiY6xroSK67CXeTu0Otmk.html
Quality: th-cam.com/play/PLAXJqmuqGEr4LQvNzKHGO9l00gEN4gmSP.html
Design: th-cam.com/play/PLAXJqmuqGEr706zgRtnwgQiFC5FYLvaTr.html
Automation: th-cam.com/play/PLAXJqmuqGEr6O_nQ-n08qmrtNnAUruj3b.html
Calculus: th-cam.com/play/PLAXJqmuqGEr7Ayo18H7tknyQAJu1OcoUW.html
Explanation is good. But its 2018 you should always show a live inspection vs alot of taking. Do a live video checking tru pos of that hole instead of talking. Talk less show more.
@@TeW33zy Comment is good. But its 2022 you should always talk with an appropriate attitude vs being condescending. Be more polite instead of commanding. Rude less kind more.
One of the best, easy to understand descriptions I have ever seen! Thank you!
Thanks for watching!
Your videos are excellent. I'm a Canadian Mechatronic Systems Engineering student reviewing GD&T, and you did a much better job in 22 minutes than my profs did in hours.
Please continue to make more GD&T videos!
Thanks! I appreciate the feedback!
3-2-1 had me scratching my head! I've been so used to CAD doing my constraints, I always assumed that I would never need to specify part orientation. I spent a few minutes confused by the datums but it finally sunk in: A references the back plane, which 3 points don't particularly matter. B References a (single) line along the top of the part, and C is any point along the right side.
This opens up a better way to not just describe and manufacture my parts, but also the documentation/use of assembly jigs and part handling, thank you!
That's awesome!! Thanks for watching and the comment. I like that this video made something clear for you.
Doc, no matter how many tines I watch this same video, I continue to get value from it.
Thank you sir, had you would have been my instructor back when I was undergraduate and graduate school I probably would have gotten my PHd.
Thanks. Comments like this are very motivational.
Please continue giving more video. I like having the video's available for refreshing my ME major knowledge.
Great introduction to GD&T. Please keep them coming. Thank you.
You are more complete than my professors were 30 years ago. They spent an entire 30 minutes on the subject. I learned most of it on the job. I had to teach this to my daughters because her profs didn't mention it.
Thanks a lot! I really enjoy knowing that people are getting something out of my videos.
this is the best ever video on gd and t ..i have ever seen on you tube.........thank you 10000 times for that
Very clear.
Very precise.
Without any unecessary additions.
I will follow this channel closely
Thank you! Welcome to the channel.
i mocked up my resume to get an inspecting job..and it worked...now I'm going into this job not really knowing anything until i watched this..definately needed the 3,2,1, rule
LMAO! Good luck!
Good Job with the 12-modes of motion or the 6-degrees of freedom...DATUMS are the key to any tooling set-up.
Thanks!
Thomas J. Vanderloop, Author, Technology Instructor & Manufacturing Contractor, CMfgE & LSME
the 321 rules is a new concept to me its like if the clouds have moved and the light shined on my face.
Very good explanation. If I can understand then anyone can understand which means the content is great. Thank you
one of the best video i have seen on GD&T
Thanks! I appreciate it!
This guy teaches better than my professor at the college. Love the video.
Even though the 3-2-1 rule is common for establishing a coordinate system, it does not satisfy ASME 14.5 for a DRF. In your example, you would need to use 3 perpendicular planes. Datum A feature would locate on the 3 highest points, Datum B feature would locate against the 2 highest points and Datum C feature would locate against the single highest point on that surface.
I'm a WELDER by trade but have worked with CNC In the past milling parts I like the video would like to see everything related to topic thanks
Thanks! Its great that you got some value in the video.
Hi, thanks for this video that you have put together. I have a few questions for you regarding it if you don't mind - I know little about machining and my questions might be a bit basic: 1. Why would the basic dimension of 16 not be measured from B, as B would be a sure reference to measure from? Why would basic dimension of 34 not be measured from C, as C would be a sure reference to measure from? 2. What importance in terms of tolerance would 10 play, it doesn't seem to have any mention? The surface that it is measured from might be rough and inaccurate when compared to the other official Datum sides (AB & C). Is it not important as to the position of the hole set (the two holes) in relation to the boundaries of the rectangular block it goes through - maybe that block doesn't need to mate up with an adjacent component accurately, but just for it to be attached using bolts? 3. The slide with the 3-2-1 Rule at time 10:02 for example, shows the Right Hand Rule and the 6-axes of freedom. The axes don't coincide in those diagrams (although I can mentally rotate them and see what's going on)...generally speaking, the z-axis is the vertical axis (elevation view) isn't it - thought I would mention this as I think most machine set ups would be with the z-axis vertical (is this the case in industry standards)? Additionally, I know this might not matter, but do you have a preference to which axis has the 3, which has the 2 and which has the 1 restrictions for movement? 4. Why is the term 'counterpart' used, what does this mean in this context - I would imagine it means equivalent part? 5. At time 14:51 it shows the ABC Datums in the control frame and you mentioned that A-Primary, B-Secondary and C-Tertiary need to go in that order and that set up, so even though, some other arrangement of the stops to hold the part in place on the machine would ensure it does not move and all freedoms of movement have been stopped, why would this order be important? Is it related to axis preference or some other preference? AB&C would all be trued up and equally suitable for datums (or are they not?) - is it to do with their specific machining tolerances? 6. The (2x) indicates the two holes I would expect. 7. To achieve a diameter accuracy of 0.001 for example instead of the 0.06 for the holes, would this mean using a more accurate drill bit/chuck/more expensive machine in practical terms - which would make the manufacturing of the part a lot more expensive? Thanks for your help. Kind regards. David.
Really enjoyed this I am a Printed Circuit Board Designer in which we do a lot of GD&T,
i love this, helps me to undersatnd gd&t better. thank you!!!
WHY are None of the dimensions given in relation to Any Datem??
The "A" has no relevance to the hole position, the "10" is on the far side from the "C" and the "16" is on the far side from the "B".
Makes no sense to me.
I agree completely with Edd
First thing, that most of the information for that part is left off. I assume that was done to leave only the symbols that the Prof. wanted to focus on.
My understanding of how "A" applies to the hole position, is that because the hole is actually 3 dimensional (a cylinder), the axis of the cylinder is to be perpendicular to plane "A". It made no sense to me until I got away from the idea that the view was a 2 dimensional drawing.
Edd is spot on. Terrible example "Professor" shame on you for adding to the confusion of GD&T. The primary "A" datum controls perpendicularity of the holes (cylinders), the "10" and "16" should be located from the datums B & C (or the datums need to be on the opposite sides where the dimensions are located from). it's fine that the "10" is not "Basic" and therefore it would be the drawing block tolerance which would apply not the positional tolerance, but for this basic lesson it probably should have all been basic dimensions located from their respective GD&T datums. It then would have been a worthwhile lesson . In the real world as presented it would force a call to the engineer and drawing change.
A,B,C in respect to What??
Very well explained. Thank you for the upload Sir.
Why am I choosing today to learn when I have a splitting headache?
Great training, could you upload GD&T tolerances for assemblies interaction.
Good explanation. The only comment I have is your orthographic projection is 1st angle projection. North America 3rd angle projection is most commonly used.
Kindly prepare video lecture on complete Gd&t and tolerance stack up analysis. Its my humble request to you
kudos to you Professor, and much thanx for this easy-to-understand tutorial of gd&t basics!
Thanks a lot! And especially thanks for taking the time to watch and comment!
Simple yet effective explanation
Thank uou
Thanks for watching!
do you plan to update your video according to ASME 2018?
Great videos man, great explanations.....my GD&T instructor is too wordy and doesn’t simplify. Thank you, thank you!!!
English isn't my native tongue and I understood this better than my mechanical drawing classes
Thanks! That's awesome!
Brilliant Dr. Cummings! Subbed and learning more!
Thanks for watching!
Very informative and helpful! Subbed. Looking forward for more videos like this from you.
Thanks a lot!
Very informative video..!!! Thanks for posting it
Thanks for watching!
Thank you . Extremely helpful.
How come the dimensions do not start from datum planes? They're all from the opposite plane. Don't all dimensions have to originate from or be traceable to datums?
Totally broken down! Thanks!!
Ty Mr.Cummins 😎
You're welcome and thanks for watching!
Excellent video. Thanks for your help.
Great training video.......
Wonderful Lectures ! Thanks.
Thank you.
Hi Professor Cummings at minute seven you talk about the 321 rule and you have 3A, 3B, 3C. you seem to refer to them as three datum planes…when actually they are the same datum planes… so why would you call them ABC when they’re all co planer?
First off, I'd like to thank you for making such an informative video!
Could you please elaborate on the 3-2-1 rule a bit? Isn't the block still capable of moving along the "+" directions of all of the 3 axes? I mean, fixture 1 stops the block from moving along the "-" direction of the Y axis, but it can still slide in the "+" direction, right?
I am confused about this also.
i believe you have to imagine the constraints being mirrored so the movement is limited on both sides!
Amazing why cant you be my professor mines suck do you teach at any cuny schools in ny like the way you teach is so intresting catches my attention and goes straight to the point
Hello Adel the turtle! Thanks for the compliment! I currently teach in Cincinnati, Ohio. Its good to know that you got something out of this video!
Infinity MFG thank you so much we need more professors like you can you do more videos on this topic showing more tolerance and dimensioning and charts and explain tbe signs like for ex the m or L and stuff like that and practice problems would be nice
Hello sir,
very good & important information
Great video learnt lots.
Good, down to the point video!
Thanks!
Z is usually up/down, x/y is horizontal, at least in circuit manufacturing
Zaph Kiel hi, in cnc machining and using a cmm the z-axis is the translation of the spindle. X and Y are relative to that. This applies to vertical and horizontal equipment.
Good basic knowledge but can you please provide some knowledge regarding datums in relation to net pads resting, 4 way and 2 way for stamping perspectives
Thank you
Excellent video.
clear and straight forward
THANKS! I appreciate you watching.
Very Helpful - Thank you!
Thanks for watching! I plan on putting up the full class on my own page. Make sure to keep watching for it.
www.theengineersreference.com/videos-2/engineering-drawings/
Please forgive me, but, since when is the "Z" axis not vertical, the "Y" out and in as viewed by the operator and "X" not right and left as viewed by the operator?
Silly question, but what is the diameter of the holes please?
Thanks for the video. Could you explain those datums and how to select those datums ?
Very Good
Great work sir!.
Thanks!
question when using an insert do I use MMC for hole?
Thanks, you do a great job of teaching
Thanks! I'm glad it was helpful.
such a awesome explanation .. really I learned something what I need. But i have a doubt like . How profile tolerance get effect by MMC ?? I have seen in some blue prints asking profile with MMC !! seeking for your answer.
Hi Raghu, Thanks for watching and commenting.
There are two modifiers that use the same symbol, 'Maximum Material Condition' and 'Maximum Material Boundary'; they use the symbol of an upper case 'M' in a circle. A profile tolerance is subject to MMB, this means that a surface is being treated as a boundary or datum feature (secondary or tertiary). This gives information to the engineer on how to design the gauge (datum simulator) so that the maximum material is accounted for.
You can get more information on this from "Ultimate GD&T Pocket Guide" - 2nd edition on page 38.
Hi sir,
So how bonus tolerance will add to the profile tolerance when some features called for profile with MMC.
So exactly how far away are the holes from Datums B & C? Shouldn't the dimensions be referenced from those 2 datums?
Thank you Sir! this was very helpful!!
thank you great video
nice work .
Ahad Memon thanks!
thanks, amazing video.!
Helpful, Thank you so much
Thanks for watching!
Why 3A 3B 3C ON THE SKETCH? Shouldn't be : A1 A2 A3 / B1 B2 / C1 ?
Good job thanks.
helpfully, thank you so much
Amazing, Thanks!
Dumb question. How do you know the dimensions are in inches and not metric?
Not a dumb question at all. Inches VS metric can usually be found in the title blocks of a drawings.
See this video for help: th-cam.com/video/M8fAF0xMxBs/w-d-xo.html
a technician once told me if the plan doesn’t specify, that metric units rarely have more than one decimal place and that english measurements usually have 2 or more decimal places
I'like this lesson in frensh. Think You
Thanks for watching!
To all the engineers out there. Please for the love of god, try to make the datum point something that's intuitive and easy to find with conventional calipers. Pleqse please please please, whatever you do, do not locate your datum off the theoretical center of a hole or radius
Sincerely: a contract manufacturer
very good intro.
Thank you so much!
Nice video and helpful information
Area for improvement: use a better microphone, it seems you are using a headset
Yeah, I replaced the headset last fall and bought fancy-pants microphone.
I thought a leading zero before the decimal point designated millimeters ( 0.01)
need tutorial GD&Tvideo implement to CMM program.
Thanks bro
Very clear and informative. Would you suggest any textbook(s) for GD&T (whether one of the 3 in amazon's top 30 in Drafting and Mechanical Drawing or some other)?
Yes, a good book is called, "GD&T Application and Interpretation" by Bruce A. Wilcox
Make videos on modifiers please
That is a good idea
Can I get more videos on GD&T
Y u didn't make basic Dim of 10 in this video?
You are using first angle projection not third angle....very confusing...totally distracted me.
Why is the Z-axis not vertical to the horizontal plane?? In segment 9:09 I see Y-axis vertical to the horizontal plane. Is this a North American thing? Isn't Z-axis always perpendicular to the horizontal plane? I had a tough time getting my point across to an engineer in Ontario, Canada. I could make out he came from the Auto-CAD world (2D) where X-axis and Y-axis goes along the Length and Height of the monitor screen and Z-axis comes towards you - the operator. This is incorrect per me. There has to be some standard. To me Z-axis always directed towards the sky.
The orientation of the z-axis isn't tied to 'horizontal' or 'vertical' per-se. Typically, X-Y-Z and the left hand rule are centered on the concept of following the device (tool spindle, inspection probe, etc) That is what dictates the Z-axis, the X and Y axis depict travel relative to that. This is why you can have machines that are 'horizontal' and 'vertical', they are telling you the orientation of the spindle.
the teacher mentions Right hand rule in video, but L H rule in reply?
the way I learned R H rule is simple, cross the X towards the Y and the Z will unscrew out of the plane. So that way you can place the XY plane at any orientation, and you expect Z to unscrew out of it. Take a look at a CAD screen and watch the results as spelled out here!
Shall I post this video on my channel with Tamil subtitles
👍
The 3-2-1 rule doesn't restrict movement in all directions. No one can machine the part with those constraints only. The worst part of your example is that you have three datums and two basic dimensions that are from feature planes that are NOT the datums. You have no idea where the holes are located with respect to the datums because you are lacking the width and length of the part. If you are picking datums, you should probably use them for your dimensions, especially basic dimensions. Part of the problem with every GD&T lecture that I've attended or listened to is the fact that the prints are not complete. I want to see how you put EVERY dimension on the print for the people in the shop who must make this part. If the basic dimensions for the hole must be from a side that is not a datum, should the width and length of the part be basic as well, so that basic dimensions to the hole from the datum are ALL basic? Show me the print as it needs to be, not partials. Even Lowell Foster, arguably the father of GD&T, did this, and it drives me crazy. Datums on a post look stupid and take up valuable print space unnecessarily. I specify 14.5-1982 in my title block so I don't have to see the concessions made to the ISO community by the GD&T committee on my prints. What purpose does the post serve? Further, I would like to know the differences between 14.5-1982 and 14.5-2009. As far as I can tell, they are the same. Symmetry went away in 1992 but came back - I don't know exactly when. On the other hand, unlike the guy who said he is "dumber for watching this," even though I do not agree with everything, I did learn something from the video. I didn't notice the "snap, crackle and pop" of the sound.
Thanks for watching and your feedback!
Sir plz provide hindi vedio
thx for this
Thanks for watching. Check out the other resources that I have available.
www.theengineersreference.com/engineers-blog/
5:18 Are you using first or third point of view? You really mention that.
Thanks
there needs to be some dimension corrections on that drawing though
Hi Teacher
where I can get this certificate
for mechanical measurement and inspection
even I have been training and worked in previous company
but like to get this certificate
sincerely
student
💜💜💜💜
WHy does it sound like there is a Geiger counter in your room?
LOL!
damn good
Thanks! And thanks for watching!
Can make tectorial more
I think your Geiger counter is on.
Basic dimensions to the 2X hole features must originate from the datum features. Not an option, major fail for an instructor to present this.
Explanation of the 3,2,1 part indexing / degrees of freedom indicates datum target simulation, this is misleading. The drawing requires planar datum simulation.