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Time savings 3D Cad Designs VS Hand drawings 30

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designmr

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Nov 29, 2005
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Does anyone know what percentage in time a design is reduced in hours based on design being done using a 3D Cad system (Solidworks)? Instead of hand drawings.

Need some numbers to help justify purchasing software for company.

Thanks, in advanced.
 
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Blue print machines. Heck I worked at Hughes Aircraft way back from 1973 to 1991, before CAD, sometimes we had to do "SUN PRINTS", yep, lay that drawing in the sun...I still have my old tools (templates, pencils, etc), not sure why....
 
And I used to walk uphill going to and coming home from school, even in the snow! (Consequently there was also a downhill side.)

Do you remember the days of Constructive Geometry? It was amazingly clever stuff, but I'm so glad I have SWX for all that now.

Designmr, what about making sepias? They were a pain to work with.

- - -Updraft
 
Showing our age? [wink]
I started with Constructive Geometry.
I worked with sepias. I hated the chemical (eradicator?) for making changes.
I still have all my templates/tools in a box stored away in the garage. I gave some tools to my son while in engineering school.

Worked at a company ~16 years ago that did hand drawings, microfilmed them, then re-microfilmed every change, signature, etc. Was a PITA!

CAD makes life much easier in a lot of ways...until the computer locks up or crashes!

Chris
SolidWorks 11
ctopher's home
SolidWorks Legion
 
""Worked at a company ~16 years ago that did hand drawings, microfilmed them, then re-microfilmed every change, signature, etc. Was a PITA! """


Ctopher, now you are bringing back painful memories.

By the way does anybody want a used microfiche viewer?

I started as a board drafter where we microfilmed, later went to Auto Cad then Cadkey.
I later discovered parametric with Solidworks and then Alibre.
Would I go back? Well maybe to Solidworks.
Would I do a hand drawing? Possibly on an A sized sheet for a small simple part, then to save it I would still have to scan it so it did not get lost. But I am willing to bet that the time would be a wash and with the solid modeling program, you can print as many copies as you like.
B.E.

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor
 
Ctopher, I remember "Descriptive Geometry", hated it.

I remember the eradicator, plus, having to use "Ajax" or some cleaner to remove large areas of ink on mylar or the "Dry Cleaning Eraser Pad (Scum Bag)"...
 
Initial design of a part by hand or in 3D CAD is not much different in time. The real time savings come when you revise that part. The automatic updating of drawing views from the model change make that step almost seamless.
There are secondary benefits in design integrity and assembly file mating.


"Wildfires are dangerous, hard to control, and economically catastrophic."

Ben Loosli
 
Talk to whoever you're thinking of buying the software from (VAR or whoever) it's in their interest to help you come up with this information. I've had SW VAR and direct folk trying to persuade me to switch to SW and they had info comparing it to various other CAD packages etc. so they may have something for your situation.

A good thing about CAD (especially 3D) is the ease of changing things.

A bad thing about CAD (especially 3D) is the ease of changing things. (You can spend a lot of time tweaking things that you just would have probably left as originally drawn otherwise.)

Posting guidelines faq731-376 (probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484
 
The type of statistics that bean counters ask for to "justify" everything are mostly ridiculous in nature. Suffice it to say that manufacturing and prototyping mistakes from unforeseen fit-up issues will pay for the CAD program by themselves.

The old saying, "You don't know what you don't know" applies here. There are so many design issues that cannot be seen in standard two dimensional orthographic drawings and must be proven in manufacturing. The amount of time wasted going "back to the drawing board" kills companies and is never documented in the true production costs.
 
Real advantage of paper drawings was eventually you wore the corners off the drawing and had to release the project.

--
Hardie "Crashj" Johnson
SW 2011 SP 4.0
HP Pavillion Elite HPE
W7 Pro, Nvidia Quaddro FX580

 
The amount of time wasted going "back to the drawing board" ... and is never documented in the true production costs.

And is often never documented at all.

The shop-floor people figure out how to make it work - regardless of the drawing - and make it right (in the works of Mike Holmes).

They store all this information in their head and somehow the documentation never gets updated.

Along comes a big truck as they pull out of the driveway...crash and all that intellectual property is gone in an instant.

Full 3D/2D digital documentation helps ensure continuity in opperations of a company.
 
rollupswx,

I am sorry. I do not see your point!

The shop builds it. They modify it and make it work. Then, they go on to the next job. Why would 3D make them more likely to tell drafting something?

People on drafting boards tended to come out of technical schools, where they learned at least something about shop operations. I suspect that a lot of modern day CAD operators have not a clue of what it takes to fabricate their parts. There is minimal communication between the shop and the CAD office.

3D CAD is an awesome tool in the hands of someone who knows what they are doing, but it is not the least bit idiot resistant.

Critter.gif
JHG
 
I guess my missing point is that the (3D) designer should find the problems (or at least more of them) before they get to the shop floor. It costs far less to make changes at the design stage.

Having spent 8 years of my life out on the shop floor as a machinist, the benefits of designing in 3D seem rather obvious to me.
 

"""And is often never documented at all.

The shop-floor people figure out how to make it work - regardless of the drawing - and make it right (in the works of Mike Holmes).

They store all this information in their head and somehow the documentation never gets updated."""

This happened with a major aircraft component manufacturer who subcontracted to build fuselages for another aircraft manufacturer.
The fuselage ribs were rolled to a z shape on a multiroll machine, then stretch formed to the correct curvature.
The company decided to get rid of the multiroll machine and outsource the rolling job.
The new rolled parts came in correct to the drawing, but would not stretch form to the correct dimensions.
I and a supervisor went to the foreman’s desk at the point where the roll former stood, literally hours before the desk was to be carted away.
Inside we found a set of marked up prints that were at least 20 years old, detailing dimensions allowing for the reduction in size from the stretching operation.
As hot as the FAA was on people not using marked up prints on the production floor, this one had dropped through the cracks.
And is a classic example of feedback from the shop floor not getting to the drawing office.
B.E.

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor
 
I agree. But common sense isn't taught anymore.

Nonsense. I think historically there is always perception that "it was better in the old days". There are good teachers and poor teachers. There are good students and poor students.
Always have been. Always will be.

We will see amazing things come from our current crop just as we saw amazing things come from previous generations.

We will also see compete idiocy.

I think we might be getting too far off track of the original topic. I understand that the OP needs facts and figures, but my experience is that no amount of "proof" will sway many people who have their mind set in stone.

Can "common sense" actually be taught?
 
"I agree. But common sense isn't taught anymore."

The other side is that many companies run on such a rushed schedule that engineers and designers are not given proper time to exercise "common sense" on many design projects. When things are rushed, mistakes are bound to happen, and then all fingers point back to engineering. What a warped world we live in...
 
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