I finished this bumper pretty much! It’s not perfect but I’m pretty happy, I struggled before because I tried using to many curves and I kind of stepped away from that approach for this model and just started with degree 1 planes and banged them into shape.
I am taking this one step further, I want to stitch it together, import it into a solid modeling package and thicken it.
In reality this is going to happen! we can’t just turn a blind eye to what happens after our work has finished, I believe anyway. You can see I am trying to stitch it, and that immediately shows me that I have a few gaps I need to fix up first.
For example these two fillet pieces don’t match up,
so I simply turn on the CVs and start snapping them together. I put curvature locators on the neighbouring edges also to check whether I don’t loose position continuity anywhere else by doing this.
Sometimes it’s a little trickier,
such as this region of the model! because the CVs don’t naturally line up with each other on these surfaces.
So what I do is, I turn off Perspective in the View Panel
and I zoom in as far as I possible can! then you can see the truth that is always with us: there is always a tolerance and unless CVs snap to each other with a one-to-one ratio it is never a 0mm gap!
So I move one CV one a little bit in, the other a little bit out as so forth,
until I find a balance which satisfies the gap tolerance for all the edges in the model. Notice the tolerances here are as such, with a gap of 0.01mm and some people go down to 0.001mm which of course makes life that much harder!
Eventually you will want to work towards having one shell with one boundary, the outer perimeter of the shell.
Now let’s export it to our solid modeling system!
First of all, I understand IGES is still heavily used in industry or perhaps even VDA but I think you really can’t go wrong with STEP and am looking forward to the new AP242 protocol due to be supported by many software in the near future! for now I would recommend AP214. I simply selected my shell and File > Export > Active As.
Now let’s import this in CATIAV5!
As you can see, it comes in as a valid, single and watertight open shell surface. CATIAV5 has a gap tolerance of 0.001mm, but allows for a thing called “tolerant modeling” which allows it to increase this distance where and when it makes sense. In this case, because we stitched it first in Alias and the STEP file supports the notion of a “stitched open shell” CATIAV5 is smart enough to understand our model’s intent, and does not give us any problems.
Now we can perform a thicken operation of say around 0.7mm to give it a volume,
and we have a solid! now not all models will be this easy to thicken, sometimes it can be a real battle! it needs to be discussed at that point whether the surface modeler will change his model, or whether the engineer will go ahead and attempt to manually thicken it which usually works but takes time!
Just a note to those of you who are really driven to reach Alias Automotive Entry Level:
When I first met Graham Bullock, I suppose I was just like most of the other aspiring wanna be modellers out there, trying very hard to understand how to build a vehicle and unable to find any help at a reasonable cost. I wasted so much time trying to learn a very skillful profession, on my own. Now when I look back on it, I can see that I had zero chance of succeeding, without having a pro. like Graham Bullock to help and guide me every step of the way. He has worked in the Automotive Industry since 1970 and not only has he taught me so much about Modelling and Reverse Engineering, but what I find really useful and confidence building, is what he has taught me about how Design Studios work and I now I definitely feel that I have a really clear concept of what to expect when I walk into a studio, to work for the first time. I am very proud to have been promoted into the Elite Student Group, where I get a fantastic level of support for my modelling. If I am stuck, Graham sends me notes on the correct work flow and when required he sends specimen srfs and meshes.
In my day job, I am currently working with a CAD package, designing wiring harnesses for trains and my dream is to get into an Automotive Studio as an Alias Digital Sculptor. Since I have been in the Elite group, I have seen students taking up jobs with Lotus, Fiat, Ferrari, Audi etc. and I know that if I carry on working hard, I will make it too! Wish me luck!
Regards, Kevin: Elite student with LearningAlias
To Learn Alias Automotive to Industry Entry level has been made easier.
For student’s who have the objective of finding a CAD job in the near future, I still teach One to One students and all of these students get Automotive Modeling or Design/Modeling jobs, so it’s a great investment to make. The hourly rate is very high and there are vacancies in UK. France, Germany, Sweden, Spain, USA, Brazil etc. I can only take a maximum of 5-7 students at any one time. I teach all levels right up to Post Graduates. I have never had a Private student fail to get an Alias Automotive job (Companies include Ferrari, GM, Lotus, Opel, Audi Seat etc. ). If you wish to apply for a place, please email me with all your details.
Why not visit my website and take a look for your self?
Over 100 videos on many, many aspects of Learning Pro. Alias
I show you how to build a Complete Audi A5 Sportback (ext.) . Over 50 Videos on that alone !
Info. on Courses:
6 Months website access to all website based video tutorials, 167 Euros (215 USD equivalent Sept. 2012)
167 Euros (215 USD equivalent Sept. 2012) per month. You get your .wire reviewed by me every 15 days and you will receive : feedback, instruction, tips and advice from me personally. Access to all videos including my ” Private Student Training Videos”. You will build at least 3 complete automotive exteriors. The course also includes an intensive Reverse Engineering section, which required by most employers.
“#3 Full Pro. “Elite” Course”.
Fast Track Full Pro. “One to One” Course with weekly reviews and coaching 200-250 Euros (USD. 260-320 approx. Sept. 2012) per month. One to One Private tuition. You will receive specific geometry and meshes and modeling from me personally where required, to help you to complete your exteriors quickly to an Industry entry level standard. This means a bigger investment, but once in an Alias modeling job you will get back what you invested many times over and be able to work anywhere in the world
NB: Typically students pay 50% of the cost of the “Elite” course by monthly installments settling the balance over time, once they have an Alias Automotive contract.
For more info,
Just register on my website and I’ll send you all the details
*** Special 25% Discounts for US students (Message me on my website for details)
If you are in the USA, just register and login, then go to Profile and you can pay your subscription with your US credit card. Absolutely no extra charges for currency conversion.
Graham Bullock B.Ed.(CNAA)Des.Tech.