Flattening solid bends

[dustin]

Does anyone have a suggestion for unbending solid bends (or spinal bends) similar to the way it is done in sheet metal? I was hoping that using flattened quilts would give me the results I need, but it appears to distort the geometry upon flattening (actually I tried bending from flat, and then created a mirror of the flattened quilt to bend back).

I have a rolled channel with slotted holes which I placed in the formed state, and would like to create a flat form so that the holes can be punched prior to the rolling operation. If I can't find a solution I will need to go back to putting the holes in the part before the bend operation and iteratively positioning them to end up in the correct position post form.

Thanks!

This thread is inactive and closed by the PTC Community Management Team. If you would like to provide a reply and re-open this thread, please notify the moderator and reference the thread. You may also use "Start a topic" button to ask a new question. Please be sure to include what version of the PTC product you are using so another community member knowledgeable about your version may be able to assist.

[merrill.rosenow]

Maybe taking a screen shot of your model and tree would help. There should be no reason you need to make the part in solid as opposed to the sheet metal functionality of Pro/E. In fact, I suggest that when dealing with a sheet metal part you do as little outside of sheet metal as possible. This helps promote a robust part that can be properly manipulated using the most different types of features availible in Pro/E sheet metal.

As far as the roll forming operation, is there a reason you cannot use the flange feature in sheet metal? If so, I remember learning about a rolling feature in the Pro/E sheet metal online course that could help you out. I can't remember the name of it off of the top of my head but can look it up if you are truely stuck.

[dustin]

Ordinarily I would do this type of action in sheet metal ... but this part is an channel, and is not compatible with sheet metal. I'll try to break down the problem a bit better:

I have a C6x8.2 channel I need to do the following to:

1) Roll to the correct form (no problems using either solid bend or spinal bend)

2) Put holes in their final position (no problems)

3) Bend back to it's original flat form (distortion issues)

4) Suppress the bend back and create a family table instance with the bend back active to show a flat representation of the part ... complete with holes in their pre-formed position.

At this point, the only way I can see to get the desired results is to put the holes in before the bend, and then have the bend suppressed in the family table instance ... but that introduces a lot of trial and error positioning of the holes, and is not as robust of a part if anything changes.

[mlocascio]

THE PLAN



RE-create this as a sheet metal part. Create a slit or some other break so
that this will flatten. Then add your holes where you want and need them.
After you have all of your holes located and the SHEET METAL PART is
complete, I would recommend creating the flat pattern.



Michael P. Locascio

[brianlynn]

Instead of putting in holes in the "formed shape", put in points, then
create holes in the flat form, after the flatten referencing the points.

Brian S. Lynn
Technical Coordinator, Product Engineering

[bfrandsen]

If you have Behavioral Modeling (BMX) you can add the holes before the
roll and use BMX to modify their dimensions so they fit in the rolled
form.

Bjarne



Dustin Hase <->
18-08-2010 15:38
Please respond to
Dustin Hase <->


To
-
cc

Subject
[proecad] - RE: Flattening solid bends






Ordinarily I would do this type of action in sheet metal ... but this part
is an channel, and is not compatible with sheet metal. I'll try to break
down the problem a bit better:
I have a C6x8.2 channel I need to do the following to:
1) Roll to the correct form (no problems using either solid bend or spinal
bend)
2) Put holes in their final position (no problems)
3) Bend back to it's original flat form (distortion issues)
4) Suppress the bend back and create a family table instance with the bend
back active to show a flat representation of the part ... complete with
holes in their pre-formed position.
At this point, the only way I can see to get the desired results is to put
the holes in before the bend, and then have the bend suppressed in the
family table instance ... but that introduces a lot of trial and error
positioning of the holes, and is not as robust of a part if anything
changes.

Site Links: View post online View mailing list online Send new post
via email Unsubscribe from this mailling list Manage your subscription
Use of this email content is governed by the terms of service at:

[dustin]

Thank you for all your responses. What I'm getting from this is that there is no way to flatten out a solid bend or spinal bend without distortion.

I chose not to use sheet metal for these parts, as it would be a more complicated work around, and would result in a part not representative of the material I am using. If only I had AAX and BMX, life would be complete! Ahh well, there are other things I can do to get the job done.

My answer is to put the holes in the pre-formed part with clever use of relations to automatically drive the position of the holes relative to the length of the part. Sketching a curve of the neutral axis gives me the developed length of the roll, so it is a simple matter of measuring the neutral axis curve length and input that number in for the length.

Thank you everyone,

Dustin Hase

[merrill.rosenow]

I should have mentioned in my original response, that Pro/E only handles bending metal in sheet metal in one direction. You are correct when you say there will be distortion. Pro/E can still deform material in more than one direction, but it does not have the math to know how this material is being drawn and thus will not change the thickness, there are too many variables. For small deformations this is not a problem. I have actually created very accurate parts using small deformations on the corners where the material is drawn so this should not be overlooked as a way of modelling. Have a good weekend everyone.

[ptc-593619]

<warning friday=" rant=" ahead=">

We use solid bends from a flattened sheet and ProE pretty much sucks at
this. We have a multitude of small graphical details on a large part -
ProE doesn't like that either but I don't want to get into the
relative/absolute argument or the extended retrieval times for patterns
of patterns - but the flattened sheet idea does not work that well for
us. The majority of the sheet is O.K. but Merrill is correct in saying
that deformation occurs in the corners. Unfortunately, this deformation
to us is not small (presumably because our graphics are so small) and
often it renders the solid bend/flatten sheet mode absolutely useless. I
know in other software I do not get this problem - a sheet can be
flattened without deformation in the corners (Ideas anyone?) - so why do
we have to put up with this in ProE? It seems that the developers
reached a point and gave up saying it is good enough for most people.

Richard A. Black
Lead Design Engineer
Eaton Corporation
440 Murray Hill Road
Southern Pines
NC 28387 USA

[gjackson]

Without going off on the limits of proE; you can assign deformation areas to
corners to focus (minimize) your error to known areas. From my experience
the biggest errors in sheet metal bending is the bend tables being different
than the equipment that is being used (i.e. press ware, tooling limitations,
etc.). Error outside that is typically smaller than most design standards
anyway. I do not know if this will help with your solid bends, but it might
help.



Greg Jackson
Design Engineer - Material Handling
BuntingR Magnetics Company
316.284.2020, ext. 141