Adding Bend

I am trying to unfold this 90 degree cylinder into a flat pattern and I can't seem to add a bend to it. I cut the whole thing in half and when I go to add a bend It's telling me it can't be a non linear edge?? So How do I unfold this then?

Are you actually doing this in Solidworks or did you put this thread in the wrong forum? Your question also appears under the post of another entirely different question in another forum.

Yes I am doing this in Solidworks and yes I did at first post in the AutoCAD forum under a post similar to what I'm doing. I will delete the other thread now. Any ideas on this?

Sorry, no. I am not a Solidworks tech. Would like to try my hand at it one day though. Well, I hope someone comes round to assist you. Good luck.

SolidWorks will not unfold that part.

Yah I found out It needs to be sectioned into 4 pieces, called a four gore I guess?? I am still having a hard time trying to figure how to draw it.

it wont do it because the metal needs to be pulled/stretched in order to make that shape. If it was just a cylinder or just a 90degree arc thats one thing but combining the two is a different story. Can i ask why you would need to unfold that?

It's a 90 degree air duct elbow. 4 equal pieces at 22.5 degrees should come out to a 90.

are you still talking about a bend? or 4 straight pieces?

The problem with unfolding the bend is the inside edge of the bend will be compressed(look at exhaust tubing that hasnt been mandrel bent) and the outside edge will be stretched. Even if you change your 90degree to smaller increments i do not think solid works will allow this. Yes the material goes through this when you bend a corner as well but when accounting for it over a linear axis the software has no issue.

This may not help you but a good rule of thumb may be, if you cant bend it with a piece of paper, you are not going to get the software to unbend it.

I'm not trying to bend the tube 90 degrees. I am talking about taking a flat pattern and turning it into the image above. I have figured out that it will be impossible to fold this in one piece and instead will have to be 4 equal pieces.

tuxarut,

It appears that you would have to approximate the elbow with something like this wireframe image. In Solidworks, you could draw something like it in sheetmetal sections, which could then be unfolded.

Here's another approach. This image is a Solidworks assembly of four sheet metal parts that could (I think) be unfolded. I am not competent enough in Solidworks to properly trim the intersections.

This is exactly what I came up with as well. Not sure how I got the dimensions but it worked. Thanks for the help.