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Sheetmetal Flange Good Idea But.....

MattMcCarty

New member
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Its just not worth it..........WF3.0 Datecode M050


I Have a three sided folded part with a 2 fold flange running around those three walls (see pic) It will not unfold, it cant't unfold unless im doing something wrong.


Created a simpler part with the same results and the accuracy was increased and that didn't work


Just wonder it anyone eles can get it to work?


Oh has anyone noticed that when you create a multiside flange wall and place the flat pattern in a drawing the axis for the centers of the fold do not display as they would for a flat wall fold?


View attachment 3724
Edited by: MattMcCarty
 
Have you tried to change to absolute accuracy?


Starting fromWF 4.0 absolute accuracy is default in shmtl.


"New sheet metal parts are created with an absolute accuracy of 0.0005 inch or 0.0125 mm. Setting the configuration option enable_absolute_accuracy has no impact on this default. The change to absolute accuracy gives you direct control over the accuracy setting for sheet metal parts. You can modify the default by changing the sheet metal part templates in the templates directory at the Pro/ENGINEER load point."


What type of corner reliefs do you use? I've found that Rip works best on complicated parts. It's difficult to see the shape of the flange, maybe it is impossible to unbend. Remember that shmtl is basicly a bending program and not a forming program.


Yeah, unbend axis not shown on drawing is a bug, see SPR 1340170. Please log a call if you have the time. Priority is only medium so far.
 
Inside Bend Radius is material thickness.


I have recreated a simple part with a flange over the three sides first fold 50 mm long 90 deg down and second fold again 50 mm long and 90 deg up sketched profile using the Flange function and creating the flange using the one feature (nice and simple i thought) and it wont unfold it.


Miter cuts on


Bend relief Rip


Corner relief Obround


Shows a preview of the 2 bends that make up the box, flat but is having problems with the flange


The accuracy im increaseing by edit>setup>accuracy and setting it to 0.0001 max allowed


Im begining to think it's a bug........Anyone able to confirm?
Edited by: MattMcCarty
 
Try and set the accuracy to absolute.


You will need to add the config option enable_absolute_accuracy yes


Change corner relief to rip. Bend relief doesn't matter in this case. It's for the relief if the flange ends along the way of the edge.


If it doesn't work try and uplooad the part and I'll have a look on it.
 
Dear MattMcCarty,


It looks like on unfolding, the unfolded portions are interfering with each other.


Try the following.


Unfold one bend at a time. Use sheet metal cut to provide relief cutswhere required. Fold back all and then UNFOLD ALL.


Trust this helps.
 
hi guys


interesting when did a search for SPR 1340170


it comes up with


Error: SPR 1340170 is not customer viewable.


Cheers Don
 
I think SPR's are customer specific, aren't they? I can't view yours and you can't view mine. Am I right on this?
 
You will definitaly need to put some sort of relief in the corner where flanges meet. You could use a "setback " on the corner to the start of the bend radius and extend the walls after. Just out of curiosity, does the flange have 2 diff bend radii? That kind of stuff drives manufacturing crazy.
 
Just lookingthe SPRis still open.


Its the second fold in the flange. I havent looked at this for so long. I just do it the hard way on the understanding that a 2 fold flange around a fold doesnt work. (Well it does work but you can't unfold it
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Does WF4 fix this? Holding off on the upgrade till around July or so. (Never buy the "A" model of anything
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"That kind of stuff drives manufacturing crazy.".........Our sheetmetal guys are very understanding.
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But do try not to make life to hard for them
 
You will definitely have to provide relief in the corners. I've let my CAD work this one out and this is what it came up with. Not working on ProE anymore professionally - they switched me to CATIA - so I can't try anything in that respect. Maybe if you do one side at a time ? The real part will have the corners more or less left out also.


Alex
 
it is....a couple of things to remember, #1 the larger the radii...the bigger the relief. #2 your relief needs only to be as large as your outside radius. You can go smaller and use a rip relief. This is ok for modeling purposes, but does present a problem to those who use the model (or Iges ) to create NC programs for turret applications. I use both Pro-nc sheet (just devoloping the process, creating UDF,s for special shape punches and forms...and writing my own posts) and I also import Pro-e Iges files to a secondary software (merry mec) to create turret programs. Depending on what your manufacturing process is, it is critical that you create the sheetmetal model with this in mind.
 
> it is


Ok. Thank you. I was wondering if there was something I was totally missing.


> a couple of things to remember


And for that as well.
 

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