Bend in rolled sheet metal

bill_daniels

Bends in flat sheet metal work great but what about bends where a rolled section transitions to a flat section?  I can't seem to make that work.

lana

@bill_daniels
Please see two examples.
If this does not help, publish a link to your document - some-one would help you.

john_mcclary

Like this?

john_mcclary

I had to start by manually adding in the cut reliefs:


Then I would be able to add a flange


Sometimes you will need to switch inner/outer 

bill_daniels

Actually, I'm not trying to add a flange.  It's more like a transition to a flat section which will have still more 90 degree bends.  I'll try to post a link to the document in my next post.

bill_daniels

This is the part

https://cad.onshape.com/documents/410b96f2236fdf1c3c3f53ec/w/382ea78034518f2c0ddf54ed/e/29cb2242c7f0c240dab7b042

The 3D part and the flat sheet metal seem to work in the part studio but the drawing of the flat sheet doesn't include all the bends.

MBartlett21

@bill_daniels

Try showing tangent lines in the drawing view

EDIT: Select the arc that should be a bend in the "Arcs to extrude as bends" selection box

bill_daniels

So, I have the 3D model correct and the flat sheet metal view correct. But, when I try to create a drawing, it doesn't come out right.  Interestingly, the phantom view I see just before I click to place the view on the drawing sheet, is also correct but when I do click, bend lines disappear leaving me with a drawing that can't be used. I've run out of options.

john_mcclary

You may want to submit a bug report

bryan_lagrange

@bill_daniels I assume you are looking to have the bend line where the large radius begins show up. 

The manual way I can see to put this is to show the tangent lines on the flat pattern in the drawing and then make a center line between the tangents to get that bend location. I made a copy of the document showing what I did:

https://cad.onshape.com/documents/ce6d0a683e96e0ffd591886e/w/45b6a3e4130879da5170a1c9/e/b5cc1b7fb38520fbfc703ff7

When making large radius in a sheet metal part and I do not have a tool to do it on the press brake or need to make a slight bend at the tangents to note start and stop of where to roll the radius I show the tangent lines and dimension to them.



Hope this helps

MBartlett21

@bill_daniels
The arc that should be a bend (with a bend line) should be selected in the arcs to extrude selection box when you create your sheet metal model.

bill_daniels

mbartlett21, The arc IS selected as an arc to exclude.

bill_daniels

This is what the finished part should look like.
https://cad.onshape.com/documents/410b96f2236fdf1c3c3f53ec/w/382ea78034518f2c0ddf54ed/e/29cb2242c7f0c240dab7b042

bill_daniels

I declare this one 'smoke in the cockpit'  My error was a subtle problem in the original sketch.  Once fixed, everything fell into place. 

MBartlett21

bill_daniels said:

mbartlett21, The arc IS selected as an arc to exclude.

@bill_daniels
Sorry, I hadn't realised