Question about drawing views

[gearman1234]

I received a drawing of a gear from a customer. On the left side he has drawin a front view of a gear. He has taken a section at 15 deg to horizontal and shown that in the middle of sheet. And on the right side he has drawn the back view of the left hand view. He has not named it as such on the drawing. I would like to know if this is a standard practice or not.

 

[dpzinn478]

It almost sounds like you have a drawing with "first angle projection." Europeans use this method, whereas Americans use "third angle projection."

http://www.technologystudent.com/designpro/ortho1.htm

http://www.technologystudent.com/designpro/ortho2.htm

http://www.tpub.com/content/engineering/14069/css/14069_156.htm

 

[PeterCharles]

PS - there are a lot of English speaking Europeans who use and prefer third angle projection.

 

[IFRs]

I use them both, depending on where the important information is and which side results in fewer hidden lines or confusing lines.

 

[gearman1234]

I would have called it a first angle projection if a side view of a disc was drawn next to the front view. But the layout is as follows.

AT the extreme left, there is the front view of disc
( essentially a circle showing different holes and so on)and a section line at 15 deg to horizontal (section AA). Next to this is a sectional view AA , which is essentially a rectangle). Next to this sectional view , on the extreme right side of the drawing , is the view of the gear ( essentially a circle). This view at Right side is drawn as if we are looking at view at the left side from back side.

So in my opinion it is not a first angle and Third angle projection. It is probably an eror or soem drawing method which I am not aware of.

 

[wgchere]

The angle of the projection is immaterial. Orthogonally, you can't get a back view from a front view with out a side view in between. And Section views are supposed to be parallel to the cutting plane: in-line with the cutting plane arrows, and 1) behind them in third angle, 2) in front of them in first angle. This rule can be violated if there is no room to place the view where it should be.

It would appear that your drawing was drawn by a proctological drafter (a quite common specialty which requires years of ignoring instruction and standards).

 

[gearman1234]

Thank you for the post wgchere.
I agree with you.