ok, i have been thru all the discussions on this topic and i am still having a problem being able to get a flat patern of a cone. i keep getting the dreaded " part cannot be bent" error. i am using the revolve thin tool. but when i try to flatten it i get the error message. does anyody have a good part they can put up so i can see what i am not doing correctly???
Good morning Douglas,
Try this one
Later,
John
Hi Douglas,
Here is another example 3 dimensions control sketch
Then revolve thin to get thickness --- insert bend ---- flatten.
Thanks
Mark (SolidWorks 2012)
THANKS MARK AND JOHN, LOOKS LIKE YOU GUYS ARE ON THE SAME PAGE HERE. THE ONLY QUESTION I WOULD HAVE IS THAT THE BEND RADIUS AND ALLOWANCE HAS NO BEARING ON THE HOW THIS PART FLATTENS??
Hi Douglas,
Not really sure what you mean by bend radius and allowance has no bearing on how it flattens.
However if the size of the flat is incorrect try changing the K factor.
Mine is usually set to 0.5 so it flattens around the mean (middle) of the thickness.
You can set this 1 or 0, if i remember correctly 1 gives a flat on the outside thickness of the plate while 0 give it on the inside.
I could though have these back to front where 0 is the outside and 1 is the inside. Memory is going.
Hope this helps
Mark (SolidWorks 2012)
Personally I would try to resolve the issue you are having determining your flats, obviously there is something amiss. K factors as well as bend allowances and deductions vary slightly from shop to shop all over the world. In 40 plus years of bending I have never seen a K factor less than .3 or greater than .5. In my experience any time you have a bend radius 10 (or more) times the material thickness you are very safe using .5.
I don't agree with those that suggest 'cheating' as once it hits the floor those guys will have your head. If they can show that it has the correct radius and the ends don't meet, it isn't their fault. Our long running joke on the floor is that the K factor is zero if the plate cracked.
In a real pinch for a flat, you can also go here: http://www.sheetmetalguy.com/cones.htm