What The Major Problem With Alibre Really Is :

[jwknecht]

Re: What The Major Problem With Alibre Really Is :

Many CAD/CAM systems don't understand faces or solids.

Please elaborate. Which CAM programs don't understand faces or solids? I can understand some 2D type programs (but those are pretty easy to program at the machine using a 2D print).

Plenty of the older ones. Many that do wire EDM, laser, etc.

jon

OK. Now that we have established that, does it make sense for Alibre to look backwards to those that have older CAM systems or does it make more sence for those with older CAM programs to look fowards and upgrade their CAM programs? Don't answer that, as it is a rhetorical question.

 

[Anonymous]

Re: What The Major Problem With Alibre Really Is :

Many CAD/CAM systems don't understand faces or solids.

Please elaborate. Which CAM programs don't understand faces or solids? I can understand some 2D type programs (but those are pretty easy to program at the machine using a 2D print).

Plenty of the older ones. Many that do wire EDM, laser, etc.

jon

OK. Now that we have established that, does it make sense for Alibre to look backwards to those that have older CAM systems or does it make more sence for those with older CAM programs to look fowards and upgrade their CAM programs? Don't answer that, as it is a rhetorical question.

Okay I won't .

Instead I will ask those who wish to at least try and be objective how you separate CAM from CAD ? Specifically how do you separate CAM from CAD in:

Pro/ E - Pro/NC - Pro Manufacture

UG NX - UG NX Manufacture

CATIA and Whatever they call their CAM

SolidWorks - CAMWorks

IX Speed and whatever they call their CAM

VX

ThinkID and the version of OpenMind Hypermill that runs in thinkID


Etc.

I don't believe that CAM and CAD can be separated as *all* of the examples above clearly demonstrate to anyone who is objective.

Wireframe is not looking backwards. It's the *foundation* for solids and surfaces. Without wireframe you can't construct a surface or a solid even if the CAD/CAM program hides it from you.

Wireframe is an essential part of the process.

You might want to read this paper several times because you seem to be struggling with the concept of wireframe and what it really is. Note it's a very recent paper authored by the person who invented NURBS and was the head of R&D at ComputerVision.

http://www.kubotekusa.com/images/pdf/20 ... turing.pdf

There is no one in the CAD/CAM business more respected then Ken Versprille. No One.

He was recently honored at COFES.

http://www.cofes.com/2004/participants/

Jon Banquer
Phoenix, Arizona

 

[Anonymous]

Re:

Jon,

Does this explanation help you to understand why a seamless, unified, hybrid modeling approach is the only approach that can deal with many real world modeling tasks ?

Thanks - that gives me a better idea of the concept. None of my work so far as required any of that functionality, though, so I guess Alibre is still good enough for me.

Mike

Not a problem, Mike. Hope what I posted gives you a wider perspective then you had and that one day the info that I posted turns out to apply to what you may be doing.

Even though the info I posted may not apply at the moment to you, I highly recommend your read Ken Versprille's white paper on geometry based manufacturing. It's an interesting counterpoint, by someone who has impeccable credentials, to some of the comments posted in this thread that have no basis in reality. IMO, I have a very good idea what tools are needed:

I will be using the tools I speak of tomorrow at work. :wink:

Jon Banquer
Phoenix, Arizona

 

[Anonymous]

Re: re: What the major problem with Alibre is

"(although recently they formed an aliance with another company to provide surfacing capabilities (as an add-on at extra expense)"

Not true. Pro E Wildfire 2 now includes ISDX 2. ISDX is developed by PTC.

"As Mibe said the real world is based on solids"

Not true. Many things are better / more easily modeled with surfaces. Try reading what I posted again. COFES conference presenter and SolidWorks user Ed Eaton has often said that solids are really surfaces with macros. I agree with Ed's definition.

Jon Banquer
Phoenix, Arizona

 

[jwknecht]

Re: What The Major Problem With Alibre Really Is :

You might want to read this paper several times because you seem to be struggling with the concept of wireframe and what it really is. Note it's a very recent paper authored by the person who invented NURBS and was the head of R&D at ComputerVision.

You can quit with the personal jabs. For your information, I told you that I learned on CV, wireframe and surfacing. I spent quite a few weeks of staying in Burlington, training in Bedford, ending up marrying a CV employee....

I appreciate the information, but please keep your posts factual.

 

[Anonymous]

I am now using I-DEAS v10 for my job and it functions exactly as this supposed hybrid modeller is supposed to. I "hate" I-DEAS and long for the day when this company moves to a real parametric solid modeler. The only real use I can see for this hybrid modeler is for the old school stress analysts that want to mesh everything by hand before plugging the part into Nastran. Since most engineers should not be doing FEA unless fully trained and experienced at it I think that the other solid modelers are just fine. I prefer Alibre because of its ease of use, support, and price. If I need to mesh something manually I will export the geometry into my FEA preprocessor of choice. Also, I agree that the machinist should not be making changes to the part w/out completing an ECO and having the engineer update the model and drawings for them!!!!!

 

[scarr]

Re: Alibres Problem

Hi Jon,
There are a few things you have avoided talking about in this discussion. Even though solid models aren't the answer to every design job, they do have many advantages over wireframe/surface based design, and these can't be simply brushed away with a seamless hybrid modelling mantra.
Surface based parts have no history tree ditto for wireframe.
Surface based models have no embedded intelligence, ditto for wireframe.
Surface based models are inherently difficult to edit. Complex wire frame models are a nightmare to edit - even if the layering conventions so necessary to their creation are followed.
The model data developed in a proprietary format .prt, CATPart, .model, etc., are a royal pain to convert for use in other systems and often require massaging before anything useful can be done with it.

Even though all parametric solid modelling applications carry the 'genes' of their ancestry (wireframe, surfaces, faces, etc.) they are a step forward in the evolution of design tools. And if solids are just 'surfaces with macros', then plaudits to the folks who developed the macros - they simply make life easier for all of us. a case in point. Filleting surfaced models was always a problem in CV and Catia, and taking a surfaced model, skinning it, creating a volume, and then using that to create a dumb solid that could be filleted just seems like a waste of time to me.
Add to that the probels you'll encounter in the future when another designer tries to edit that part. Hybrid modelling applications have been around (perhaps not under that moniker) for a while and have their place in the design world. Adios Jon, and much luck in the future selling this particular brand of snake oil.

 

[Mibe]

Re: re: What the major problem with Alibre is

"(although recently they formed an aliance with another company to provide surfacing capabilities (as an add-on at extra expense)"

Not true. Pro E Wildfire 2 now includes ISDX 2. ISDX is developed by PTC.

"As Mibe said the real world is based on solids"

Not true. Many things are better / more easily modeled with surfaces. Try reading what I posted again. COFES conference presenter and SolidWorks user Ed Eaton has often said that solids are really surfaces with macros. I agree with Ed's definition.

Jon Banquer
Phoenix, Arizona

Not true? So you mean that real world objects are surfaces with macros? :roll

 

[scarr]

To all,
Jon seems to be a regular contributer to more than a few CAD forums, and he drags his negativity (disguised as impartial objectivity) around with him like a dead dog (living in the Southwest I'm sure he'll get the connection). I think he's either a hired gun for an un-named CAD vendor, or he's trying to raise nay-saying to an Olympic sport. Either way, take whatever blandisments he voices with a grain of skepticisim. Just Google Jon and see what pops up. Being casutic carries its own penalties in the public square. You may be as imaprtially objective as you say, but that's hardly the way the world sees you. Jon I'm sure you're a great guy but your personal attacks on the users of this forum are uncalled for.

Alibre works for the people who use it, most of whom I believe aren't involved in industries that require a lot of styling surface data. Alibre doesn't advertise their product as something it isn't. They're not trying to be all things to all people and the cost of Alibre reflects this. It's an affordable, parametric solid modelling tool, that doesn't have an equal in the market place when you look at features vs price. I'm sold on the application, because it works, because it's easy to learn and use, and because it is such a fantastic value. This will be my last post on this subject, and my apologies in advance to the readers and forum moderator. I don't usually get this worked up by a guest contributor.

 

[jwknecht]

One of the moderators here. I think that Jon and all others (including myself) that have replied have had ample discussion and propose that we lock this post from further discussion? I can't believe that there are other points to be made on the topic at this time.

Motion made to lock the post. Do we have any seconds?

 

[scarr]

I'll gladly second that.

 

[Anonymous]

Amen!

 

[swertel]

As another moderator, I've been watching this thread. So far, there haven't been too many personal shots or anything that goes completely against the codes of conduct, so I've been letting it progress. A discussion like this, as long as "my cad is better than your cad" doesn't begin, is beneficial in determining market need and development direction. Possible enhancement requests may be realized by this open discussion.

I do think it is getting tiresome and starting to move out of scope of the original post (which was never really defined).

I vote for locking this thread. If this topic warrants more discussion, then start a new thread with specifics so we can keep a discussion on topic.

 

[wfpelletier]

Locking thread

I think that locking this thread is an excellent idea, and I vote that the moderators lock it.

wfpelletier

 

[mtauer]

stick a fork in it!