Re: [CAD_CAM_EDM_DRO] RE: Paper dwgs, was programming by hand

As a machine designer of many years experience I can tell you that a lot of
those out of scale drawings done by hand are due to altering existing
drawings by the simple expedient of changing dimensions and/ or making minor
rvisions. This saves a great deal of time and money when the new parts are
similar enough not to require a complete new drawing for the new part.

Smoke

-----Original Message-----
From: Doug Harrison <prototype@...>
To: CAD_CAM_EDM_DRO@egroups.com <CAD_CAM_EDM_DRO@egroups.com>
Date: Saturday, January 13, 2001 8:43 AM
Subject: Re: [CAD_CAM_EDM_DRO] RE: Paper dwgs, was programming by hand

>
>----- Original Message -----
>From: <dougrasmussen@...>
>To: <CAD_CAM_EDM_DRO@egroups.com>
>
>> Another thing about electronic files..there isn't any guarantee
>> they'll anymore right than a paper drawing. Just had one today, the
>> dimension on the drawing said one thing and the inherent dimension in
>> the drawing file was different?? Every see CAD files where the
>> entities that would represent a tool path are not connected? They
>> appear connected on the screen and on paper, but they might have
>> larger end gaps than the CAM program can automatically compensate
>> for. I see that one all the time.
><much snip>
>
>Virtually every CAD file sent to me has so many errors (line disconnects,
>holes placed incorrectly, etc.) that I have to -
>
>1. Redraw them from scratch so the CAM will accept them, or
>2. just print them out and program by hand.
>
>The problem stems from widespread lack of Proper training, even among
>professional draftsmen. When the colleges first started teaching CAD they
>were not fully aware of it's potential. The instructors tended to teach
>"board" habits, such as changing a dimension by editing the number instead
>of changing the actual feature. Line disconnects often come from sketching
>a line so it looks right instead of entering coordinates. Many tech school
>grads don't even understand cartesian coordinates.
>
>How many of you are still getting drawings with the archaic "do not scale
>drawing" in the title block? Give me a minute to put on my flame suit. If
>the drawing is done correctly (so as to be at all useful as a CAM drawing)
>then it should be to scale. I used to fight this battle by scribbling

"DRAW

>TO SCALE" across any such drawing and sending it back to the drafting
>department for rework. Made a lot of enemies this way. It doesn't help
>that today's drafting department managers and tech school instructors were
>trained in methods that don't work anymore.
>
>Doug
>
>
>Welcome to CAD_CAM_EDM_DRO@...,an unmoderated list for the

discussion of shop built systems, for CAD, CAM, EDM, and DRO.

>
>Addresses:
>Post message: CAD_CAM_EDM_DRO@egroups.com
>Subscribe: CAD_CAM_EDM_DRO-subscribe@egroups.com
>Unsubscribe: CAD_CAM_EDM_DRO-unsubscribe@egroups.com
>List owner: CAD_CAM_EDM_DRO-owner@egroups.com, wanliker@...
>Moderator: jmelson@... [Moderator]
>URL to this page: http://www.egroups.com/group/CAD_CAM_EDM_DRO
>FAQ: http://www.ktmarketing.com/faq.html
>bill,
>List Manager
>
>
>