Sheetmetal bend reliefs - not working

I must be doing something wrong...
Running thru the exercises in the Cadquest Sheetmetal book
and when I specify a bend relief it doesn't seem to work,

it looks like a bend without a relief.

Maybe I'm missing something.

 

: I must be doing something wrong...
: Running thru the exercises in the Cadquest Sheetmetal book
: and when I specify a bend relief it doesn't seem to work,
:
: it looks like a bend without a relief.
:
Mike, the only time you'll see the corner relief (stretch or rip) is when you
can't make the bend or wall without it. If you have just one bend on a straight,
flat piece, there won't be any relief to see, even if the program lets you specify
a relief. Also, you won't see or need relief if you build walls to the inside of
the first wall, i.e., your flat wall sketch doesn't cross the thickness of the
metal, but moves away from the metal. That will place the new wall outside the
perimeter of the first wall. So, even if you use outside radius and make it stock
thickness (which makes the inside radius sharp), all the material goes to the
outside and you've made the width of the box larger by a stock thickness. That
means that there is no overlapping of material where two walls meet at the corner,
so no need for corner relief. If you are not sure which way the metal is going,
use 'Tools>Measure' to see if a dimension grew by at least a stock thickness.

In the following case, you will need corner relief:
You have a first wall. Let's say it's oriented horizontally and has two vertical
walls attached to the left and right sides. Then you wish to add a front wall
between the two end walls and make it so the the outside face of this wall is
flush with the ends of the side walls. This wall is formed into the metal,
preserves the front to back dimension of the first wall and needs some kind of
corner relief so that the metal at the corners gets out of the way of the bend.
But, you can make a lot of bends and walls without needing corner relief. This is
something it takes a while to 'get', even with systematic instruction because
they're not actually teaching you sheetmetal design, just how to do it with Pro/e.

David Janes

 

Mike, the only time you'll see the corner relief (stretch or rip) is when
you

Thanks David for your detailed reply.
This is exactly what the book shows, one flat piece with one bend with
reliefs
and it shows the different types of reliefs graphically.
So I expected to see it because it's in the book.

What if I want a bend relief where it's not physically necessary?
....and I want it as part of my design?

Pro E just won't show it and has no way TO show it?

Thanks

Mike

 

I don't have proe in front of me, but i think to put a releif in where it s
not needed, you'll have to offset the sketch from the wall (if extruding),
or sketch the wall dimsnioned a small differnce from the points (if using
the wall with radii)
cheers
Craig

 

: > Mike, the only time you'll see the corner relief (stretch or rip) is when
: you
: > can't make the bend or wall without it. If you have just one bend on a
: straight,
: > flat piece, there won't be any relief to see, even if the program lets you
: specify
: > a relief.
:
: Thanks David for your detailed reply.
: This is exactly what the book shows, one flat piece with one bend with
: reliefs

I am at a complete loss. I just can't visualize where there would be relief or
what would be relieved on a flat piece with one bend, unless the piece was
T-shaped and you were bending the leg of the T into a vertical wall. And then only
if the bend was inside the border of the cross member so that a top view shows the
cross member to be the same dimension, top to bottom, across the whole width of
the top member. In any case, since this is hard to describe adequately and
pictures/models would help the discussion immensely, maybe you could iges the part
and post it somewhere or send me a copy. The picture of what it is supposed to
look like would help too, since I'm not convinced we are even talking about the
same thing.

: and it shows the different types of reliefs graphically.
: So I expected to see it because it's in the book.
:
: What if I want a bend relief where it's not physically necessary?
: ...and I want it as part of my design?
:
Again, I can't visualize what it would be or what it would look like if didn't
represent the reality of how metal bends.

David Janes