I posted a topic about changing to SW in January. I recieved very good information from this group before we launched into a time consuming comparison of which software will work best for us into the future.
It looks like SW came out ahead for how we will use it. I'm not happy about changing but a 30 day evaluation and some demonstrations in our data sets gave some definite reasons to change. I am about to approve a few hundred thousand dollars of engineering time to make the switch beyond software purchase costs. We are not casual users (see our products at www.entrusttool.com) and I believe we are using Inventor as effectively as possible. If any one has direct experience with the following primary deciding factors I would appreciate a rebuttal before I start the process next week:
#1: Configurations .vs iParts and iAssemblies: I even went back to Autodesk VAR training on this one with one of my engineers to make sure we weren’t doing it wrong. I have generated thousands of iParts and still find them slow and cumbersome. The multiple child concept and file structure makes using them a serious commitment rather than a natural flow of design. Using them for multiple states of a casting with machined features is not practical. iAssemblies are about the same, the parts count was wrong in the bill of materials during the VAR class and required several forced updates after it was noticed before the bill of materials was correct. This is an every day advantage for switching to SW.
#2: Weldments: Inventor forces us to design each piece as a separate part, and then machine them afterwards. Using the weldment environment for machined features (essentially assembly level features) slows large assembly performance per white papers from Autodesk and our experience, so we use derived components of the welded assembly to create machined parts. Heavy investment in skeletal modeling was made several years ago to make this go more smoothly, but a simple copy of a weldment for reuse in a new design is a serious time commitment. I asked the VAR about Vault and redirecting a new dataset to a different master sketch but wasn’t comfortable with the answer. SW uses a multi-body part environment and is smart enough to recognize multiple plates/stock the same size even when created as sketched extrusion and breaks them out into a parts list. Coupled with configurations for machined/welded state, SW is superior for our products.
#3: Drawings: SW is quicker for detailing, auto dimensions from user selected datum’s .vs only model sketches. Complex sectioning is possible, Inventor is still lacking in basic functions. I want to pay my engineering staff to design parts, not detail them. The .dwg compatibility focus is not important to me, nobody uses Autocad anymore for serious machine design or machining, CAM is always 3D in our industry.
#4: FEA: We run IV 2008 pro and Simulation versions with ANSYS part FEA. We cannot use this tool on assemblies, so essentially it isn’t very helpful unless we manually attempt to simulate relationships in separate parts and I personally only trust the results in very basic cases. Cosmos in the SW premium works across multiple parts in assembly mode and appears more useful in actual design. I got pricing on ANSYS designspace but it even though the link is dynamic, it isn't as accessable to the designer (and it is expensive to purchase and maintain).
#5: The basics: Sketching constraints, intersecting bodies, etc. is not as simple as it could be in inventor. Modeling features such as extrusions at offsets, different dimensions in different directions and assembly context geometry projection and sharing relationships seems smarter in SW.
#6: Industry acceptance: It was about a 20:1 ratio of SW to Inventor experience on resume’s. We hired two mechanical engineers to expand our department that had Solidworks experience. Both said they were willing to learn Inventor and I’m sure we could train effectively if we had to. Our CAM software Mastercam just announced live geometry links between Solidworks models and their toolpaths. According to our salesperson, no plans are in place to develop this for Inventor. Many of our supplier can read SW models, all of our suppliers require us to step out our Inventor files. There is a definite stigma against Inventor as an inferior (cheap) product.
I do believe Inventor is superior in some ways:
Performance: Large assembly opening was actually faster in Inventor (although the parts came from native Inventor construction stepped out for the test), about 35 seconds .vs 50 seconds on a 4000 part assembly (With lightweight parts on, SW opened it in about 15 seconds). Rotating models on the screen, creating drawing views and selecting edges on huge drawings was somewhat quicker with Inventor on our 64 bit $5k workstations. We can open an 8600 part assembly in Inventor across our network (no locally stored libraries) in 3.5 minutes in shared mode, without Vault.
Interface: SW2008 looks like Microsoft Office 2007. I hate Office 2007. I am obviously more familiar with Inventor, having used it 50-60 hours a week since R5, but even adjusting for my comfort level, I believe Inventor has a very elegant user interface.
Graphics: The native inventor textures, shading, etc. on parts make it enjoyable to work in a realistic view without resorting to obnoxious or performance sapping “special modes” that SW offers. Good job Autodesk (since the beginning this has been very good.)
Threads: Inventor can show left hand threads, SW cannot (really, it’s true.)
Support: Access to file downloads, service packs, discussion groups without requiring subscription (although we are on subscription so I guess this doesn’t matter.)
Any final suggestions or thoughts are appreciated.
Anthony Fettig
Chief Operating Officer
Entrust Tool and Design Co., Inc.
Menomonee Falls, WI
www.entrusttool.com