Come on, greenimi. I find it hard to believe that you are not able to find the outcome. You who's able to mine through the forum like noone else and need just one word I or others said to start a conversation ;-)
Kedu,
I am assuming greenimi is looking for confirmation that the rules for the...
Your last question may easily turn into a philosophical dispute as there are people, I'm pretty sure, preferring different approaches.
Doesn't the base plate mate with something? The large bottom surface must probably sit flush against something, correct? What features of the plate are...
I was thinking about making the bottom surface of the plate a global primary datum feature and two other features on the plate as global secondary and tertiary datum features. These could, for example, be left side as secondary and the height as tertiary. I don't think there is a need to define...
True if the dowel pins are designed to constrain X translation only.
Edit: I wonder what mechanism ensures that the side plates remain in firm contact with the locating edges in the base plate.
Per para. 7.15 of Y14.5-2018, the selection (hence also the number) of datum features should be based on the functional requirements of the design. Additionally, in para. 7.14 the standard says that more than one datum reference frame may be necessary for certain parts again depending on...
greenimi,
Burunduk said it well and I would just add one thing to that. In order to make J-P's first drawing compliant to ISO in terms of the completeness of mutual spacing definition between the two features, either:
(1) CZ modifier needs to be added to the existing callout, or
(2) another...
3DDave & Burunduk,
It looks like the apparent peace between the two of you, that I asked for in this recent thread and which you have respected since then (thank you for that!), couldn't last forever. So let me repeat my request and, at the same time, quote the Posting section of the Eng-Tips...
Target points are mentioned at least twice in the original post.
In my opinion, the terminating dots in the original illustration mean as little as the fact that the circular symbols used in that illustration are not datum target symbols at all.
Besides, if the entire surface, and not just...
This is just nit-picking, but to be precise, CZ elevates any callout to an orientation and location control between the features in the pattern. It is not able to impose external constraints to datums.
J-P,
If the picture on the left (with position) was per ISO, then the callout would merely control perpendicularity of the holes to A. The spacing between the holes would be left uncontrolled, so in order to turn it on, CZ would have to be added after the tolerance value. It's because the...
Garland23,
As previously suggested by Ryan6338, if we follow the logic that the symbol in the first compartment of the tolerance indicator defines external constraints of the tolerance zones (i.e., constraints to datums, if they exist) and CZ defines internal orientation and location constraints...
I'd just like to say that the two dimensioning and tolerancing systems - ISO and ASME - while appearing quite similar at first glance, are actually pretty different in many places. Some of the differences are details, but some are fundamental.
I also believe that perpendicularity used with CZ for datum features B should be an allowable option. The fact that it would control relative location of the features in addition to the orientation to the datum plane A shouldn't be a concern, otherwise flatness with CZ shouldn't have been...
There have been countless debates on the figure 8-18 and I am not sure another one is needed.
The whole reason I made that additional comment was to suggest that in the OP's case a similar dilemma might exist. In other words, there may be a need to clarify whether the "origin plane" of the...
rollingcloud,
You have not specified which version of Y14.5 you have in mind, so if, by any chance, it's the 2009, the figure you may want to look at is 8-18.
Notice that the "Means this" portion of the figure may be a little deceptive as the as-produced datum feature B is shown perfectly...
Burunduk,
I don't think I have a problem with the availability of both determination methods. It's just a matter of wordsmithing the datum target definition properly such that the inconsistency we are talking about doesn't exist.
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As a relatively long lasting member of this forum...
I don't think this would help solve the problem. To ensure consistency, the definition of datum target (para. 3.21) should rather list more target types, including planes and spheres, which I believe Burunduk alluded to.
I am not sure I would agree with this. Figure 7-60 is easy, but in fig...