>You see- funny thing here- by constraining all my sketches, and doing my best to have a clean part, I SAVED NO TIME.
In my experience all the evidence I have seen is that constraining most sketches and using a disciplined modeling technique saves time.
I took a look at the file. As indicated earlier in the thread no other changes other than adding the fillet after Extrusion15 the part would rebuild without errors. I don't believe I ever indicated that there was a cause and effect between the unconstrained sketches and the fillet. I believe I did indicate that this was an interesting file because a fillet feature caused errors earlier in the history tree.
I frequently take interesting problems from this discussion group and analyze them see if I can reproduce the geometry in a more efficient manner - particularly those problems that might reveal a re-producible bug or feature missing from Inventor. I identify with the book iWoz by Steve Wozniak on how I enjoy these challenges.
It was pointed out recently that while I might post a more elegant, robust solution I never take the time to explain why it is more robust or elegant. It would probably take a book to go much beneath the surface, and I am basically a machinist, ill equipped for the task. The first thing a machinist does when making a part is identify data for reference.
I checked iProperties and it indicated the file was started in Inventor 2008 and last saved in Inventor 2009.
I opened your file and created a new user Workplane Inventor assigned Workplane23.
On the workplane I created a new sketch Inventor assigned Sketch107.
In the new sketch I created a rectangle and added a dimension, Inventor assigned d872.
I Project Geometry a Loop, Inventor assigned Project Loop60.
I Project Geometry a Cut Edges, Inventor assigned Cut Edges28.
I extruded the sketch and Inventor assigned Extrusion87.
When I go through a problem I try many many iterations in quick succession getting to understand the geometry. I start many new files rather than building on top of the earlier garbage that I have accumulated and then discarded. A couple of interesting reads along this line are Seymour Papert's Mindstorms: Children, Computers, and Powerful Ideas, and The Children's Machine: Rethinking School in the Age of the Computer. To paraphrase Papert, "I need the unsuccessful early trials to get a feel for the later successful solution."
Workplane23
In your file there remains 9 user workplanes. Three of these are duplicates of the origin workplanes.
The only time I duplicate the origin workplanes is if I need to Flip Normal or if the design indicates that I might want to offset later for some reason. In other words, very very rarely. I feel like I might be mis-interpreted here, I didn't say I don't create user workplanes, I said I don't duplicate workplanes that already exist.
Sketch107
In your file there remains 42 sketches and 3 suppressed sketches. Many to most are under constrained, often lacking auto constraints or any dimensions at all. It would actually take me more time rather than less time to do the unconstrained/undimensioned sketches. To me this is the "quicksand" that can lead to even inadvertent changes to the model even if you were very careful in the initial construction. Even if you will have absolutely no need to change later. Within those sketches is evidence that is of more concern to me than the dimensioning/constraining - after all we didn't have constraints or driving dimensions on the drawing board or even AutoCAD.
Project Loop60
I failed to record how many projected loops you have remaining, but I almost never ever use projected loops. They are particularly prone to failure if the underlying geometry changes too much. Do an experiment. Project a loop on a face and then sketch a circle. Extrude the circle. Now try to Copy the cylindrical extruded feature. You cannot copy a feature that contains projected loop. (Projected Loop is generated when the Project Geometry is used on a part face rather than on the edges.) It gets even more fragile if build a child feature whose parent has a projected loop. Only use projected loop on top level features that will never change and no use as iFeature or Copy in the future.
Cut Edges28
I failed to record how many projected cut edge sketches you have remaining. Similar to projected loops, projected edges are prone to failure if the underlying geometry changes too much. But unlike projected loops which can be entirely avoided in any case that I can think of off-hand, projected cut edges are sometimes very valuable. They should be used only where absolutely needed and with caution. Until recently they weren't eve associative in Inventor. (I feel the need to point out to the less experienced Inventor user that Cut Edges28 does not mean there are 27 previous entities created - each instance of a project cut edge usually (always) results in multiple entities created - each of which could fail).
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
"Josh_Petitt" wrote in message>Like
title="news:6060974@discussion.autodesk.com CTRL + Click to follow link"
href="news:6060974@di......
Phil, I will routinely rely on "sloppy design practices" and usually get away
with them.
This is an attitude that reflects your company's culture. If
you are sloppy in one aspect of your work, you will usually be sloppy in
others. This also affects the work of your peers. This is nothing more than
laziness.
It is has become very obvious that ADSK does not practice
continuous improvement or Six Sigma and relies on "good enough and lets hope
they don't notice". The release of sloppy code and half-implemented features
is a regular occurrence. Features are not fully documented. Websites are
updated with broken interfaces. It is all connected.
I would suggest
reviewing your attitudes and culture otherwise you will continue to lose
customers to other companies that continually strive for excellence.
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
"Dennis Jeffrey" <
title="mailto:djeffrey@teknigroup.com CTRL + Click to follow link"
href="mailto:djeffrey@tekni...> wrote in
message
title="news:6061040@discussion.autodesk.com CTRL + Click to follow link"
href="news:6061040@di......
Troy,
I don't think that JD or I ever have said that
underconstrained geometry is the cause of all problems. However, when a part
goes "South" for no apparent reason, it's one of the first places to look. We
had a term when I was doing and teaching computer programming back in the 70's
and '80's, called "Spaghetti Code" which described coding ( programming) that
became so convoluted that it was next to impossible to locate the real cause
of a problem. The solution to that issue was to teach a "structured"
programming workflow. When code is simplified and structured, it is more
stable, faster, and generally easier to troubleshoot.
The same applies to modeling techniques..... BTW, the term
GIGO (Garbage In Garbage Out) was coined by programmers who finally realized
that it takes LESS time to properly program ( "model" ) than to fix
issues later ( that is IF you can unravel the problem ).
I'll agree, that an issue like this rarely rears it's
head.... but as I stated in another post:
"Kinda like smoking while fueling your vehicle. I see people
doing that every day also. Sometimes there's an explosion......"
--
Dennis Jeffrey, Autodesk Inventor Certified
Expert
Autodesk Manufacturing Implementation Certified
Expert.
Instructor/Author/Sr. App Engr.
AIP 2008 SP2, AIP 2009-SP1
PcCillin AV
HP zv5000 AMD64 2GB - Geforce Go 440, Driver: .8185
XP
Pro SP2, Windows XP Silver Theme
title="http://teknigroup.com/ CTRL + Click to follow link"
href="http://teknigroup.com">http:/...
Can't find what you're looking for? Ask the community or share your knowledge.