correctly quote a technical design

[_Pietro_]

Good evening to all.. .
You know me already a little bit about this forum...(I don't know if that's good) :biggrin:

however we come to us:
today I have finished my mechanical exercise (examination simulation) and tomorrow morning I will deliver it to 8.00 split. . .
for this I ask you (engineers, designers etc.) that you are experts in the matter of taking a look at the design that place to criticize it and recommend what to add/modify (especially regarding quotas). .

thanks for the attention and x possible answers. .

 

[_Pietro_]

I apologize but I cannot attach the design! ! !

Could someone explain to me briefly how to do it? ?
thank you..(the drawing is in .jpeg and I have it on the desktop)
[se posso fare una critica al forum critico l'interfaccia che dovrebbe essere un po' piu' EASY, se non posso mi tappo la bocca!]

 

[Marco74]

try to change type of image, there is an open discussion just for related management issues, which for a while does not work well, maybe try to change even the browser if you have two installed.

 

[_Pietro_]

 

[_Pietro_]

try to change type of image, there is an open discussion just for related management issues, which for a while does not work well, maybe try to change even the browser if you have two installed.

I did it! !

 

[Fulvio Romano]

I take a quick look... I don't have time to look at all the drawing. I immediately jump to the eye that a turning object (the tree) does not quote like that.

all that is obtained at the lathe should be quoted at fan and not with successive quotas.

 

[Er Presidente]

do not use quotations in series if not for a single step (horse type).

you decided a reference, use it and "point" the odds from that face.

the diameters, you don't need to write what's going on, the lather gives him a saw. you have to put the tolerances according to what is to be mounted.

Hi.

 

[mariom]

but the depth of the seat of elastic rings??? ? Maybe I saw her.
and the section line brings it out from the edge of the detail, and why then two references for geometric tolerance "a" and "b"?? ?

 

[sampom]

. I immediately jump to the eye that a turning object (the tree) does not quote like that.
all that is obtained at the lathe should be quoted at fan and not with successive quotas.

do not use quotations in series if not for a single step (horse type).
you decided a reference, use it and "point" the odds from that face.
the diameters, you don't need to write what's going on, the lather gives him a saw. you have to put the tolerances according to what is to be mounted.

I agree.

then,
There are no quotas and those that are there seem to be "push a little there" in bulk.
I'd check back before I delivered. .

greetings
Mar

 

[Preparation-H]

Hi.

I did not understand what are those two quotas "60" from the center of the seat by key to the "center" of diameter 40 for the bearing...

However the diameter of the bearing must be tolerated according to the diameter of the hole itself (if you chose it from the skf site you will certainly have the size).

on the right side you will have a bearing tolerance and one for the toothed wheel, same speech for the left side, one for the pulley and one for the bearing. (I doi -0.01/-0.03 for pulley and to facilitate bearing assembly and 0/-0.005 for bearing)

Hi.
p-h

 

[Preparation-H]

but the depth of the seat of elastic rings??? ? Maybe I saw her.
and the section line brings it out from the edge of the detail, and why then two references for geometric tolerance "a" and "b"?? ?

are not there, or are blind in 2, and I recommend that they be the h13 (referred to the width) for the h11 diameters (I forgot to specify)

Hi.
p-h

 

[sampom]

... or we are blind in 2

3.

greetings
Marco:smile:

 

[folle76]

Buonasra is a...
by orma know you already a little on this forum...(I don't know if it's positive)

I would restrict the tolerance field to be applied to this "quotation" (quotation).

 

[stefanobruno]

I don't want to go into the quotation, they have already responded correctly in many.
if the type of piece has been set to you, I stop here.
If you made it up, I suggest you remove all the seeger locations except for the two ends.
the positioning of the various elements you get by interposing of the spacers.
I don't know how that tree has to work, but I've seen more than one break in the seeger area.
I have just assisted my son (4° itis) in a drawing task and I live to cry to see what they make you draw.

Bye.

 

[Meccbell]

> all the quotations of the distances of the seeger sites pity: there is a mixture of functional and constructive quotas that would cause confusion even the best of the lathers.

> there is no trace of tolerances on coupling diameters: a dozen posts in another discussion about how to choose a bearing and then "zeru tituli" for the couplings.

> the quotations of the quarries for tabs have difficult references to be used during the processing: better use only one reference for each of them, which could be or the shouldering towards the center of the tree, or the front face of the tree itself.

> geometric tolerances: apart from what has already been said about not having to use 2 references for the same geometric entity (the axis of the piece), it is not understood well why then everything is reduced to a single tolerance of perpendicularity and there are not both the other indication on the other side of the shoulder of the central d. and above all there is no indication of concentricity on the coupling diameters bearings/wheels/puleggia.

in my time a design would not have been accepted by the teacher.
in the present day would simply be sold to men in the workshop.

excuse the apparent roughness, but if this is the result of 2+3 years of study, then we are in the high sea.

 

[stevie]

We're not... we're not here. .

I add other considerations:

- the quotation of bearing and tooth wheel seats deserve different tolerances
- the material has been imposed on you (I'm curious to know by whom ) or have you chosen it?
- I don't understand the reference "a" of geometric tolerance to what it serves.. .
- the "60" share to what is it?
- missing the diameter of the gorges
I hope they're additions you made on the jpg...

 

[gerod]

I say:
- arrows are not homogeneous
- lack tolerances on diameters, etc (mh is average and maybe you need a fh)
- the font size must be homogeneous
- the quota lines should not be intersected by the reference lines
- missing the depth of the seger (what did he say? )
What's the reference to? ?
- if you use a reference you call not to call the sez a (you could mess up)
- missing the total length

 

[_Pietro_]

Here I am.

I thank you for all the tips and I realize I am not able to draw a piece correctly.
I decided that tomorrow I will not deliver the report although this will penalize me of 1/4 votes...(my penalty goes up to 3/4 votes in less) but if the design is such a crap worth losing a bit of score and do something as you must. .

Now I read the whole thing well and analyze point by point the whole discussion so as to make the necessary changes and then redesign the table as you must
In the meantime I put the question of examination so you get an idea of what it required and understand the usefulness of this tree. .

 

[Mr.Panda]

What? Maybe he wanted to write mk!!

However wrinkle 0,8 should not be indicated in that way on the section a-to the quota of
diameter must be radial the roughness you have to quote in the prospectus of the piece.

a and b???? Can you tell me how to mix them? puts indicate plans... but such are not...
how do you take a reference to measure the orthogonality of the surface compared to the plane to if a plan is not!
You should if anything turn it into an axis ... draw a quota that takes into diam of the tree out of the figure ... and then not put the size but put on the arrows the quaint with the a...so indicate the axis of the tree...

for the rest you do not share so much to raglio ... you have to put yourself in the role of the lather ... but also of the meter that arrived the piece in production will have to first control it ... baptizes therefore one zero that is your origin for the lav. and for an evfentuale sist. di rif. of measurement.

the derived quotas like the tot. go in parentheses remember ...!

If you add the missing quotas and the systems a little could go well for the school ... but if at work in a ut present something like that ... (at least from my parts in Veneto ) you feel flying a series of blasphemies that bend the crucifixes!

I give you a dispassionate advice if you want to learn well to make the tables take the three books of the straneo/consortia - design of mechanical constructions , vol.1-2-3 ... or (but is less complete than the strange ) the manfè-pozza-scarato always 3 volumes .. are both published by the principality.
You will always need them in your working life!! are books that never grow old!!

Remember! ! here inside the sellers of cad 3d often claim that the table does not serve anything that the tables are exceeded etc...

fake! I have worked 4 years in one of the most prestigious Italian motorcycle houses, a world champion brand of motogp!

...I really learned how to make the tables! the care of the tables was maniacal!! every time I had a slight doubt I always consult the norms....

Why? In the 3D Kingdom? because the table is in fact a legal document on which you can contest the job to the supplier or department running the piece If the supplier expires and the table contains errors of things that are not in accordance with the rules, it will stick to those cavities, otherwise if the table is perfect and correct from the normative point of view, it will attach to the tram and it will have to respond to the error!
often in large companies where you work with pdm the boards are passed 3 times ... before you and you have to self-approve , then from your superior ... and then from the manager of ut or design ... before you go out to the shopping office!Good luck!

 

[_Pietro_]

this is the original question:http://www.itisteramo.it/esami_stato/2006_temi_e_soluzioni/meccanica_2prova_tema.pdf