problem modeling rail traction hook

[accipiter84]

at university I am modeling with solid edge a traction hook.....
I own the design in 2d that I have attached of which I know the sections aa, cc, dd, ee and the view from above.
I tried to model it with if through various "solutions" (loft protrusion, sliding protrusion, cutting with surfaces, sliding cuts and revolution cuts)........
at the end I opted for a modeling at strokes (working section by section) and combining everything with a Boolean feature; in doing so, however, I had to make simplifications to the sliding geometry (date the "just fitting options between the sections" I know).
the result I got is shown in the other figure (I can also send the file part if necessary)

given my ignorance I wanted to ask you:
Would you know how to give me some advice on the proper working method to model it decently?
solid edge is good to model "easy" (x-d) this hook or do I have to turn to some other software with which I can manage the scrolling of sections? if what?

thanking everyone for the precious info I have already found and that I will find on the forum...

greetings, tommaso

 

[gerod]

It doesn't seem complicated.
I would use the protusion and then work on other features.
if it also allows you to use the surfaces! !

from what I see it is not difficult to realize the piece but are only hypotheses not having under hand the constructive design but only a part.
Hi.

 

[accipiter84]

Thank you very much for the prompt response. I tried to shape it with the surfaces (taking away what didn't need the initial protrusion as you suggested), but when I went to replace the faces, the program "becomes restless". ....

attached the other parts of the design...... .

carrying out a slide excavation I found problems in connecting the dd section to the cc section (the cc section is normal to the sliding curve, while the dd section does not).

 

[folle76]

post something extra. I see you also use proe from the profile. Maybe I can help you with that.

 

[accipiter84]

unfortunately this is all I have: front view; view from above and the three sections.
at the moment I have not available pro-e (no at home, nor at university)...I can make the hook itself, solid works or catia (which, however, I have never used).
thank you for the prompt answers,

greetings, tommaso

 

[accipiter84]

I tried several times to shape the hook again, but nothing to do.
I can't find a suitable sliding surface without changing the three sections I have available.
As a result, in fact, I have stresses in section cc 20-30 mpa greater than I expected.

I will continue to look for the solution and keep you updated.

greetings, tommaso

 

[folle76]

You should post the.iges to better understand what you did. cmq I think I can tell you that you have to keep in mind two things by shaping with the surfaces:

1) you have to work on "cutting and sewing": disassemble in many more surfaces than you can believe your "skin" and restore the tangence between them by means of fittings (in which case the two surfaces must be overlapped (the fitting the "cuts")) or by imposing tangency constraints between the edges of the surfaces themselves (the "cush" modes).

2) you must respect the sections that have been assigned to you. among them you can do what you want by keeping a certain "regularity". in this a parametric cad is of fundamental help because you can impose dynamic modifications to profiles or points so that you can respect any additional constraints that will be imposed on you or, more simply, you can adjust the things so that the analysis of curvature, of the deformity or what else confirm that "to the eye" there is a certain regularity.

I attach the subdivision to the picasso that I would adopt to shape your hook. It is clear that a definitive answer to the type of subdivision would only give it to you by shaping the piece. in addition to the sections you have, I think you have to "invent" (to be adjusted progressively) an intermediate support section to allow us to pass the surfaces.
surface modeling (especially when constraints are few) is an iterative process. It's a little cross and delight.

p.s: I see that your hook from the view in the plant has a lightening that is not present in the sections. How come?

 

[accipiter84]

thank you very much for the prompt response,
What you posted to me seems to be a good idea for the resolution. I'll try tomorrow morning.
attached place the .igs file even if I think I will go to work with the surfaces as you told me (otherwise I will give myself to solidworks or the cat)

greetings, tommaso

 

[folle76]

I saw your hook. In fact the tangences jumped here and there and there are a couple of subsquadri. Let's say he would horrify a printer...:smile:
cmq what I told you is valid for all cad. in proe you make use to make that swept hook with variable section, revolution, limit blend and fitting + any tools of rifilo. in sw (I only saw it a couple of times) these functions will have another name but they will do the same thing.

 

[folle76]

attached example of size and sew + or - successful. You see how to tear the piece apart otherwise you don't come out.

 

[accipiter84]

thank you very much for the many straights,
I think the printer, after seeing the cockpit, is seriously thinking of jumping directly from the ravine...

Now, however, the modeling method is much clearer.

Thank you so much for your help.
greetings, tommaso

p.s.= the hook should be that of the figure

 

[gerod]

I'd say good work.
years ago I had modeled a hull of a boat and a shovel of a pump slipped with if: I used as base blue dots points.
in the tutorials there is an example on how to do it.
in the forum there are also discussions on the topic and I think they are quite dated (say 2005-2006).
Hi.

 

[accipiter84]

I think the excellent job is for mad86....

gerod thank you very much for the help, now I will try to do as you say and mad86 (also giving a look at the old discussions as you recommended).

I've done some tests today with the surfaces, but I still have to get a bit of dimesity given the disappointing results.
I will keep you updated on progress.

Thank you very much, greetings
Tommaso

 

[folle76]

Anyway, in case you're doing thesis or a project for the university, let me take over my old days. in the department in which I had the thesis the doctoral, thesis and the researchers worked with matlab to integrate numerically systems of differential equations or simulate neuronal networks and conducted analysis of sensitivity on the results of any simulation f.e.m. (ansys, Moldovaflow, forge, who has more to put it). we grinned millions of data and as a result we had: "the great point is obtained by increasing the x-resistant section of 5%". panic!!!! because no one could take the cad and make the change to close the project. lucky one of the second year went by and worked by his father, we called him and he fixed the "casino".

 

[accipiter84]

the thing is not comforting at all.......
))

we hope to dress up for the second year and solve the mess....because for now it doesn't come to head.... .

greetings, tommaso

 

[siou]

at university I am modeling with solid edge a traction hook.....

Hey, I'll put what I did.
- profile scrap
- cross-section
- Scratch sectioncc
-School sectiondd
- a fourth sketch to improve bending from cc to dd
- a derived curve
-a divide curve
- 8 bluesurfing
- three blue surfing to close the whole
-cutting that allows to form a solid

greetings

 

[accipiter84]

Thank you so much for what you posted....
apart from the orientation of the sections it seems to me well done.... I also tried with bluesurfing but with really poor results.
tomorrow I try this new method of work.... .

again thank you so much......... you can't imagine how I have improved in modeling in this short period...... thanks to your precious advice. . .
))

greetings, tommaso

 

[gerod]

I also thank Mr Siou for his contribution.

apart from the orientation of the sections it seems to me well done.... I also tried with bluesurfing but with really poor results.

It's not easy to use bluesurfing because, in your case, what happens between one section and the other is not defined.
You will see that with some evidence you will get results.

 

[accipiter84]

place my first experience with bluesurfs.


absolutely to improve! !

 

[folle76]

I'm also workaddicted. a little something I guessed, but it's all absolutely in continuity of the first order (tangence). for the continuity of the second order yet I am not ready. It takes an additional form and a little study.
cmq I'm sorry it's in proe. If I want this summer, I'll try solid edge. apart a sform that lacks this hook that you see I would give it to closed eyes cool to the molder.

I would say that the.iges can be used for your structural simulation. At this point I ask you could post me the photos of the hook attack so I complete the model and show it to the grandchildren I don't have?
http://www.youtube.com/watch?v=hcr1geuzfq0I send you a link also to you tube of the video that I shot in which you see how I built it. I may make available the proe model (I must hear the big maxopus head) in the proengineer forum. In my opinion there are some interesting things if a approach to surface modeling.

Monday if I have time to make a table to know if everything comes back.