unbend a blend/general

Is it possible to unbend this? Please see the picture and the attachement 2006-10-19_015515_UNBEND.rar


View attachment 2798


I created 2 sketch's in 2 planes that are not parallel as you can see and then made a blend/general/select sketch and the result is this. Then converted the part to sheetmetal/shell with a thickness. Can't figure how to unbend it. I tried converting the edges to make edge rips, rip connects but I can't select any edge. It keep saying "
Inappropriate edge selected."


I thought because I didn't created the part directly in sheetmetal maybe this is a reason for not working. I created the part in sheetmetal with blended wall but still I can't create any conversion or unbend it.


Thanks.

Why don't you edit your post and remove the link to that 500 KB
video clip so it doesn't annoy someone besides me? Is there a
reason you can't post a 50 KB part?


I don't know what problems you might be having ripping but I'd
venture a wild guess that you have surfs in there that are not
developable creating the part that way and it won't flatten anyway.
I'd start with parallel planes and trim.


I'm pretty sure there's a similar part in Files that you could use
as an example, maybe others scattered about that a search would turn up.
If not, what version of Pro/E are you using?

Vlad,


The edges of your part are not 90 degrees to the wall surfaces. Sheetmetal doesn't know how to deal; with that.


Sip

Is this what you be talking about?


View attachment 2809

Create Edge Rip, select ripped edge as a reference for unbending and voila.

I didn't wanted to post a 50KB part because I don't want to put someone to dothe part for me, I was just looking for some guidelines on how to do it.


Like I said before I can't use edge rip, it doesn't let me select any edges, so this is not working.


I also tried to make a cut on one face, instead of a edge rip, but still doesn't unbend it.


Seeing that nothing works to unbend, I started to think to other options. Because this will be a big part like 500mm x 800mm (one section) and 500 x 500 (the other one) with a thickness of 6mm (steel) it will be hard to bend the part exactely like I want. So I now making a welded assy.


And it's related to this:


[url]http://www.mcadcentral.com/proe/forum/forum_posts.asp?TID=32 286&PN=1[/url]


Thanks.

Hi Vald,

If you have a small quantity from this part, and don’t want to spend too much on
the press tool, I would like to suggest to make it on universal bend machine
with step bend method. That is simple and will work even with the 6 mm
thickness sheets.

View attachment 2819View attachment 2820

Peter Bo

Yes that is want I wanted to give them a step bend on the bend machine, but seeing that I can't unbend that part I'm going with a welded assy.


Because most of the parts that I have for this project will be welded, this is the only one that I tried to bend. But I guess I should have a talk with the client to see what he prefers. Until now he let me to decide all this.


But anyway, I haven't try to bend it like yours.Can you give me a step by step example of how you did yours.


Thanks.

If you decide to go back to the original problem; having the
part and examining the goemetry saves guesswork. You should
be able to rip that thru one of the planar faces with a
curve. Have you check Gaussian curvature on the driving
faces? I'd guess that, since I can't see the geometry, you've
used circular arcs all around and that will result in
undevelopable surface that the sheetmetal function won't
unfold without defining deform regions (and you don't want to
go there for that part, I'd think).

Hi Vlad,



Try this: make your blend from solid, than make 3 individual
point (ratio) feature: one on the top round edge two on the bottom. Make plane with
this 3 points, use solidify to cut with this plane. Make a group from these
features and pattern. Make also radii on the edges if you like. After it you
can switch to sheet-metal and shell the part, unbend and done. Don’t leave any blended surface on the part except the flat
ones.

Peter Bo

Hey all,


I've been away for a few days.


Thanks for your help but I finally went with a welded assembly. It seamed easiest and quickest to do.


Thanks again.


Vlad.