choice reference line of symmetry

[Max-C]

Good day to all,
I would like to ask you if on a technical drawing (e.g. in 2d rectangle 50*10) I can choose as reference the line of the symmetry of the elements (dò symbol of reference "a" to the line of symmetry and quoto dx and sx 25-25) or I have to choose by force one side...
thanks in advance

 

[sampom]

too generic question.
to do what? for what purpose? What is the context?

 

[Max-C]

to use it as a reference for example to tolerances of positions such as holes... generic context, a perforated plate for example.. .

 

[pagnotz]

Why not? but depends on the functionality of the piece. If distances are important on one side, go to quota than that. If you want to give importance to the symmetricity of the holes, you can quote them compared to a symmetry line.
I can quote from anything, but there must be a reason.

 

[Max-C]

Why not? but depends on the functionality of the piece. If distances are important on one side, go to quota than that. If you want to give importance to the symmetricity of the holes, you can quote them compared to a symmetry line.
I can quote from anything, but there must be a reason.

Thank you.
I found slides that told me it was wrong to take a symmetry axis as a reference. having found the strange thing, and I wanted to get your feedback.
Thank you very much

 

[cacciatorino]

Thank you.
I found slides that told me it was wrong to take a symmetry axis as a reference. having found the strange thing, and I wanted to get your feedback.
Thank you very much

That way of listing is of course. Wrong. If you have to check a share compared to a geometry that does not exist, for example during acceptance testing, will you explain how you would?

the way to quote = . = reported to the axes of symmetry is part of those old healthy habits that we should leave behind if we want to progress. it used once when working on the tecnigraph it was hard to put two odds instead of a symmetric. Now that we have electronic calculators certain savings are no longer convenient.

 

[Max-C]

That way of listing is of course. Wrong. If you have to check a share compared to a geometry that does not exist, for example during acceptance testing, will you explain how you would?

the way to quote = . = reported to the axes of symmetry is part of those old healthy habits that we should leave behind if we want to progress. it used once when working on the tecnigraph it was hard to put two odds instead of a symmetric. Now that we have electronic calculators certain savings are no longer convenient.

thanks hunter,
so in that case I no longer take the symmetrical axis as a reference but one of the two sides right? (I miss the delay but for one reason and for the other on the forum I only make a jump every now and then ).

 

[TECNOMODEL]

I do not see it so wrong as quotation, any 3d control machine creates axes, centers, reference points where necessary.
if the reference is the symmetry axis, the piece is kept on the outside and the necessary axis is created.
then from that they go to the quotas.
Moreover, in certain processes it is convenient to have the quotas referred from the center, in the phase of placing the outside and you are placed on the half-car.

 

[pagnotz]

All right.

 

[Max-C]

I do not see it so wrong as quotation, any 3d control machine creates axes, centers, reference points where necessary.
if the reference is the symmetry axis, the piece is kept on the outside and the necessary axis is created.
then from that they go to the quotas.
Moreover, in certain processes it is convenient to have the quotas referred from the center, in the phase of placing the outside and you are placed on the half-car.

in my own way it would not be entirely wrong but in law it is not allowed because, as he said, [MENTION=38]hunter[/MENTION], you could not measure virtually the accuracy of the quota and its tolerances.