Rolled bends 1

[123654789]

I'd like to make a rolled bend from sheet metal. When I select edge for "Fixed edge or face" tab it doesn't accept this edge. What exatly should I do to roll a sheet metal obgect?

 

[TheTick]

Try making the part in its formed state before turning it into a sheetmetal part. Then you can select that edge as the fixed edge for adding bends.

This works for making rolled tubing models.

 

[123654789]

I tried doing it with a simple rectangular sheet. Those are the steps I did:
Sketch a rectangle
Add planar surface to it: insert->surface->planar
Then Thicken it: insert->base->thicken (1.00mm)
Then I selected an edge and press "Insert Bends"
Click ok, and it says "You must select a fixed planar face or a linear edge on an end face of a cylindrical face"
May be there is something wrong in this process?

 

[CorBlimeyLimey]

123456789 Hope I spelt that right
May be there is something wrong in this process?
Hmmm Yup!

The reason it is not working for you is because the solid you have created is not a sheet metal part. You cannot add bends to a non sheet metal part.

If you are using SW2001 or earlier, the simplest way is to do as The Tick says. Draw the rolled profile (an incomplete circle) and then "Extrude Boss" and select length & thin-feature options as required. When extruded select the "Insert Bends" feature and then select a linear edge. After that you will (should) be able to "Flatten" the part.

If you are using SW2001+ or later, the simplest way is still to draw the incomplete circle but then hit the "Base-flange/Tab" feature which will automatically turn your profile into a sheet metal part.

In both cases the fixed edge or planar face can be changed to suit what is required.

Why are you using such a complicated method of creating a simple rectangular solid? All you need to do is create the rectangle then "Extrude Boss".


CorBlimeyLimey
Barrie, Ontario
faq559-863

 

[123654789]

Well, you see, I need to create an embedded linked table in Excel for the object I create, and it responds only to the generi sketch dimentions. I made an object, which included a sketch and then boss extrude and other tools from menu, like patterns. Then, when I created a table in Excel and embedded it into the project, but only basic values, sketch dimensions responded to the table (changed according to the data in it). Base extrude and other tools did not respond to the table, so I decided to try it with rolled bends, because then I could just modify the sketch itself in the table, so that the entire part would change accordingly.

 

[CorBlimeyLimey]

1) You still didn't answer why you were using a thickened surface to create a simple flat rectangular solid.

2) What version & SP of SW are you using?

3) When you say you "created a table in Excel" do you mean a Design Table?

4) What do you mean by "embed it into the project"

5) If you double click on the feature you are trying to link to in Excel, all the feature dimensions will/should be available for selection.

6) As I stated before, the Rolled Bend feature will not work if the part is not a Sheet Metal part and going by the method you posted, your part is not a Sheet Metal part.



CorBlimeyLimey
Barrie, Ontario
faq559-863

 

[123654789]

There are the answers for your questions
2) I use SW 2001

1) I tried to make a sheet matal from a base-extrude and Surface-plane+Base-thicken objects, but the result is still the same.

3) Yes, it is a design table, I make them in Microsoft Excel.

4) Insert->Design Table, then open file dialog pops up and you can pick any table you created before.

5)Double clicking does not work, I do it by right-click on the dimention of the sketch, going into properties, and copying the full name of a dimention into the table.

6)Even with a sheet-metal object the rolled bend still does not work.

I made a revolved object from a simple rectangular sketch (like a narrow stripe) 300 degrees around an axis, and then the object would accept an edge in the flatten bends dialog window (the same results were achieved when I cut a circle and then extruded it)

Thank you for your prompt, it was really helpful.

 

[JNR]

If I remember correctly that far back, SW 2001 does not do rolled sheet metal. I think it only does bends, not rolled parts (ie: like brake press -v- roll forming). Also I think there is some confusion here. What the guys are telling you is that you need to create your part in its AS FORMED state FIRST. Ie. You model the FINISHED ITEM. THEN you insert your sheetmetal features to UNFOLD it. It is then a sheetmetal part as SW knows it. It is not apparent from your posts that this is what you are doing. This is the only way SW does it. In fact it is really the only way virtually everyone wants it, since otherwise you would have to prefigure bend allowances (or the equivalent stretch for rolling). You can still edit the resulting flat pattern part and do stuff to it, then have it refold automatically for you.

Next thing. When you have a design table open, if the next appropriate cell is highlighted for a new parameter (column header), then you can double click the dimension of whatever object is appropriate and it will automatically show up in the cell. If you do not have an appropirate cell highlighted, sure, nothing will happen. On the other hand, NEVER leave a cell that already has a parameter highlighted and go back to your sketch, because the first time you click something, it will overwrite the cell!

If my first statement is incorrect, and SW2001+ does do ROLLED parts, try doing the example in the tutorial (or what's new) first and make sure it works.

I am also confused about your surface thicken features. That kind of construction method is usually only necessary with very complex topology. What does your part really look like? Most parts can and should be constructed using simpler types of features. stuff created by surfaces and thinkening may not be recognized MATHMATICALLY as true conics (circular arcs) but as spline/parametric curve type geometry (even though they MAY be identical in shape). Without a TRUE radius to start with, bending and rolling may not be possible. SW does not handle stretch forming, which is what this would amount to for solving mathmatically.

Be naughty - save Santa a trip.