Complaining about ASME Y14.5 Changes 1994-2009

I discuss two changes made between the 1994 and 2009 versions of ASME Y14.5. These changes are not mentioned in appendix A of ASME Y14.5-2009. The changes apply in 2018 as well.
The first is the requirement to have basic dimensions and tolerances in associated feature control frames have the same number of decimal places, the second is the placement of datum feature symbols on feature control frames.

[@muscleweb]

Great video. Your first complaint regarding tolerance is a problem I have encountered many times throughout my career. Much appreciated!

[@RDeanOdell]

Thanks so much! I know this topic is very niche, but it’s something I was excited to make a video about. I’m happy you added your input!

[@rageisyourweapon]

MBD (Model Based Definition) is the direction that industry is heading toward. I understand your frustration regarding the mismatch of precision between a drawing and a 3D model (I have seen it myself many times). From an industry point of view, we are often told (depending on the customer) that the model takes precedence and, at that point, we must disregard the drawing if it comes to an argument of precision. I believe that the standards are trying to support the industry.

[@beatz5125]

Hi Dean, great video. I have actually seen the first ‘complaint’ cause issues in automotive design. When interpreting tolerance stacks there are unconsidered interference conditions that can cause problems for design teams when the parts come in within drawing tolerance, but do not assembly as per the design teams wider CAD assembly intent. It is important for designers to make sure they are not ‘rounding’ out of habit in their CAD drawing softwares.

[@RDeanOdell]

Thanks so much! I usually don’t make “opinion” videos, but these two changes really bug me. I had an issue with the basic dimension/ CAD model recently because I tried to get with the times and not worry about decimal places. I’ll go back to doing it the 1994 way and making my decimal places match.

[@Wendy-zl8kv]

Thank you sir

[@RDeanOdell]

You’re so welcome! Thanks for watching.

[@ariel59864470]

Thank you very much :)

[@RDeanOdell]

You’re very welcome!