Dear members, Problem is supplier has drilled the 4mm holes from opposite face. But we are contemplating it's a drawing error where details mentioned are not enough. can someone point out the errors in this drawing? Thanks.
As far as your question, 2 important things may be missing - depending what else is in the drawing not shown. A. Is this shown in 1st or 3rd angle projection? B. What is the tolerance on depth?
A is a good question. B: answer is .16 to .18 inch deep. Views are correct. There are things you could do to make it more obvious what needs to be done. You are showing tangent lines in the circular view. The tangent line at the outer edge happens to be very close to the location of the 12.515 ledge. This could lead a person to assume the wrong side for the holes. The view is correct because if the round view was actually looking at the right side of the section view, you would see the steps near the id, the view given is smooth. My judgement is drawing is not wrong, shop made a mistake. That said, if they can make a mistake then it means you can do things to make it more clear. Like Make the section view pass through one of the blind holes to make it obvious where it originates. Turn off tangent lines.
The drawing on the left side ... shows the top down view from the top face of the 10.5" dia boss down to the top face of the flange. This is the view from left to right on the section drawing over on the right. But this current drawing on the left should not show the 10 holes @ 4 dia. The draughtsperson should have drawn the drawing on the left, as looking from right to left in the section drawing. Simple as that. Then the 10 holes @ 4 dia holes would actually be visible. Draughtperson should have clearly written ....... Drill 4 dia holes from this side. This is what you get when "draughtspersons" come straight from college into engineering companies. They should be down on the shop floor working machines for at least 10 years, so that they can suffer "draughtspersons" who come straight from college.
