[green]"Art without engineering is dreaming; Engineering without art is calculating."[/green] Steven K. Roberts, Technomad
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MadMango-
Your response is fine if a checker is only concerned with "crossing the Ts and dotting the Is." One would think that a checker should be more concerned about the DESIGN of the product than with the DELINEATION of the product. After all, a crappy design can be beautifully drawn.
If you can, get a copy of Boeing Drafting Standard, BDS-1018. It is a pretty thourough checklist (however much of it's list is specifically geared toward Aircraft industry specific design requirements.
One would think that a checker should be more concerned about the DESIGN of the product than with the DELINEATION of the product.
If we are talking about the difference between good and bad design, this is not the responsibility of a checker. It is the responsibility of the engineering project manager / project engineer / lead engineer / design engineer to be responsible for the performance of the product. A checker (unless you only make a very few products) should really be more of a breadth of knowledge than a depth of knowledge. This breadth is usually in the form of, "lets assume that the design engineer has created a part that will function properly and meet all requirements... how best do I describe this part in order to get it manufactured and inspected."
If you are looking for a checker to determine if a product will meet its performance requirements, then there are bigger issues in the system.
Wes C.
------------------------------ When they broke open molecules, they found they were only stuffed with atoms. But when they broke open atoms, they found them stuffed with explosions...
We have a checker, they check for:
drafting standards (line type, fonts, etc)
MRP BoM and solid models match each other(but not for completeness/correctness)
The host of other requirements fall upon the ME, Designers and Project Manager:
overall design
mechanical requirements
manufacturability
component GD&T
tolerance stack-ups
material and finish selection
routings
other
[green]"Art without engineering is dreaming; Engineering without art is calculating."[/green] Steven K. Roberts, Technomad
Have you read faq731-376 to make the best use of Eng-Tips Forums?
YES. My last job had a psycho woman as a "checker". She actually sent a dwg back to me and told me "It's not pretty enough". I put it back on her desk and told her "I'll make it pretty for you if you show me the spec that says to do it!". She signed it and let it go.
Chris
Systems Analyst, I.S.
SolidWorks/PDMWorks 05
AutoCAD 06 ctopher's home site (updated 06-21-05)
FAQ559-1100
FAQ559-716
Different checking standards for different companies. They are tailor made for the most part. The most effective checker that I have known checked for (among other things):
drafting standards
tolerancing standards
material and finish standards
manufacturability
It was not his job to tell the engineer what material or finish to use, just that the material and finish were suitable and available. He did not specify what tolerances to use, just that they be used properly. He was not an engineer, and his function was not to design the product, but to ensure that the proper methods were used to document the product that was designed.
I must say I find it amazing that companies pay people good money just to tell someone that the fonts or linetypes are wrong, especially when as ctopher says when questioned about why they are rejecting something they actually have no idea.
Still it must help keep the companies tax bill down right up to the point they go pop.
I don't think that you understand the nature of checking. If the drafters/designers/engineers would only LEARN and USE what the proper rules are (see the standards listed by MAdMango), checkers would not be necessary. And not all checkers are created equal. It is good to question their authority and make them show you in the standards why they are right.
Are you one of those people that feel it is perfectly fine to dimension with thick phantom lines and cut sections using thin centerlines? By your post, it seems that you really don't care.
A proper drawing has a language of its own, and to prevent any misunderstanding as to what is really being defined, there are conventions to follow. Those conventions are in the standards. If you feel that parts of them are silly and don't effect the final product, good for you. But where do you draw the line? How can you specify that you are following the standards if you cherry pick what parts you want to follow and ignore the rest?
Ewh, I do understand the nature of checking, I have over thirty years of experience as a draughtsman, designer, engineer, and strangely enough those terms have different meanings in the UK to the USA. I own a small contract design company so presentation is very important to me if my company is to stay in business.
Frankly someone who thinks it is okay to dimension using thick phantom lines would be looking for another job from day one, I expect certain standards from qualified employees.
Could I afford to employ someone to check this and nothing else? No I couldn’t.
I still find it amazing that any company can, especially as when questioned why they have no idea why, as in the post by ctopher.
I was a checker and designer for the better part of the eighties and nineties. The company I worked for made Class 8 trucks (Big Rigs) and employed over 80 engineers and a dozen or so drafters. It was my job to enforce those company standards that were relevant in order to ensure compliance. The company would produce an avarage of 190 drawings per week. In an assembly-line working environment, you can't afford to have one of those drawings go unchecked against company standards (not to mention ANSI Y14.5) due to the potential for thousands of scraped parts. It's much cheaper to employe a checker than it is to throw parts of that magnitude away. When too many people do too many things differently eventually someone in authority asks "...can we standardize what we're doing here?".
I do not doubt the importance of checking that the drawing will not produce scrap, but for me that is down to design, tolerance and the fact that it is drawn/ modelled to ISO (in my case) standards.
Does any drawing produce scrap because the font size is wrong?
My philosophy is like this. All professions involve varying degrees of salesmanship and self-promotion. If I had to choose from two designs that have equal merits I would quickly choose the one with the best drawing package. First impressions are important. If a junior engineer or designer designs and drafts a part and puts forward a drawing for my review that does not meet industry standards and widely-known drafting practices, my first impression is that the person (regardless of the merits of the design) may have done a poor job. I'm more likely to check every aspect of the design. The design may turn out fine but that person did not get off on the right foot.
A well drawn part makes a good impression and says to me that this guy likes to cross his T's and dot his I's. I know it's not entirely rational but that's the way it is!
In the engineering profession, drafting is a language. Those who best speak this language are more likely to succeed.
The "show" is as important as the "content". If you can't communicate you design and do it well, then you might have a tough few years in this career.
I am also a fan of taking the time and effort to produce drawings that are as "pretty" as possible. Draftsmen are cousins to artists in many ways and need to have a bit of personality in their work. Were I work, there are three, maybe four, people producing "drawings" of differing degrees of professionalism. Usually I can tell who produced the drawings at first glance.
ajack1.
Point taken. In your situation, you have the ability to choose employees whom you can trust to do a proper job.
In larger companies, this isn't always the case. Often people will be brought in with little practical experience and a desire to improve (read cheaper). Checkers then take the place of teachers or mentors as far as proper standards are concerned.
One of the reasons we see so many poor drawings in industry today is because companies, large and small, are squeezing their budgets, and checkers are then seen as non-value-added. People are now expected to check their own work before it is released, so silly mistakes get thru and seem to multiply. It is very difficult to check your own work without putting it aside for a period of time before attempting it. You become blind to your own mistakes.
ctopher's situation isn't (I hope) the norm in industry. That type of checker IS non-value-added. Whenever I disagreed with a checker, I asked them to show me why they are right. Much more often than not, I was wrong, but I understood why. This went a long way in establishing good habits and learning the "language".
ajack1, use the wrong font and a 5 can look like a 6, 8 or 9 (and vice versa).
[green]"Art without engineering is dreaming; Engineering without art is calculating."[/green] Steven K. Roberts, Technomad
Have you read faq731-376 to make the best use of Eng-Tips Forums?
