Problem with broken-ot section and hidden edges

I take it your maybe a young person then. Back in the old days when we leaned against a solid lump of wood, sharpened our lead on sand paper and poked our eyes out when we fell asleep the golden rule was and as far as I know still is (could get flamed here) "NO HIDDEN LINES IN SECTION VIEWS".

If you're going to tell someone they don't know what they are doing because you assume they are young, then, yeah your gonna get flamed. A break out view is a combination of a section view and a regular view, so hidden lines are perfectly fine. Also, if you section a tapped hole you always show the tap lines. See sections 3.9.8.9 and 12.4.6.9 of the DRM and pull your head out. Boy did you hit one of my pet peaves with that first sentence.

so, we can assume that you are, also, young? :~)>

According to my Books and from what I was taught in College, hidden lines are not to appear in section views. Quote from the book I'm reading "Sections are used primarily to REPLACE Hidden-line representation; hence, as a rule, Hidden lines SHOULD be omitted in Section views."

So whether Thomas is young or not is irrelevant. But I have to agree with Brian that hidden lines are not suppose to exist inside of a section view. Unless they are teaching something new in the classrooms or in published books of today.

Regards, Scott

In general hidden lines are frowned upon in *standard* section views because they are just clutter, which was very well stated in your book's quote. However, according to the Drawings Requirement Manual ANSI Y14.100-2000 hidden lines are acceptable in *broken-out* section views. Under section

3.9.8.9 "Broken-Out Sections", Figure 3-34 shows exactly what Thomas was asking about: a broken-out section view with hidden lines from holes showing elsewhere on the part. I was teaching a class on drafting at UC Berkeley about 7 years ago and it was the same then.

Tap lines are required when a tapped hole is sectioned, so to Thomas' original question yes, these should remain and not disappear. I asked my detailer how he handles this bug and he said he simply draws them back in with lines. Perhaps there is a better way.

As far as my age, bob zee, I'm old enough to know it would be stupid for me to reveal that on a public newsgroup ;->. As my former CEO once said, "It's not about age or experience, but about excellence."

Scott: Thanks for the backup, that's the way I was taught. I had a good look thro ISO drawing standard VOL 1 and VOL 2 today, but could not find anything to conclusively back up my statement.

Mickey: I merely mentioned that Thomas "MAYBE" a young guy. This was not meant to be in anyway inflammatory, just a view that today's younger generation of designers have possibly only ever used a CAD system to do there designs and take whatever the system outputs as being correct to there particular drawing standard. Also the Tap Line is not a hidden line; it's a graphical representation of the root of the thread.

Cheers Brian

Hi!

Thanks to Mickey for the answer. Could have thought of that myself...

Anyway, as far as what the age is concerned, I am still in training at university. And the problem with the lines appeared when I tried to do my homework "copying" a drawing in CAD from my teacher. She requires me to do it as in the handout. And my personal opinion is that hidden lines are ok when you want to show that there is a hole through the part and at the same time want to show a threaded hole. Can't tell you the DIN standard for that. Anyway, I thought I try doing it on our student edition at school because I think that ACAD is stupid but maybe I have to use it since its an ACAD course :-). That is my oppinion.

Thomas