Cone with crim

We manufacture a mixer drum. They are 92 inches in diameter and 280
inches long and are tapered on both ends. We manufacture the drum in
sections. The coned ends had a crimp to help assembly and make a area
for a fillet weld. The problem I can NOT get Solidworks (2007) to flat
pattern the cone section with the crimp. Does anyone have any answer or
a way I can make the flat pattern??

Steve

I have an e-drawing if interested.

 

I would be interested in seeing the drawing and any fix as well.

Tom

 

Its not a developable surface.
It's a non-developable one.
ONLY developable surfaces can be "unfolded"
(developed) and not even all of them.
You could make it as two developable surfaces perhaps ...

There are bits of software floating about to kluge a picture
of things that are sort of like unfolded non-developable surfaces
(could they exist) but none of them can produce accurate
*unfolded non-developable surfaces*. There can be no such thing.

Perhaps a non-linear package ... <G>.

 

Model the part. Generate a flat pattern configuration. Cut off the
things that don't unfold. Add them back when the part is flattened.


John Kimmel

 

The cone flattens to a section between two arcs with a common
center and the same start & end angles.
The other bit flattens to a flat strip of constant width & the same length
as the arc.
You need the flat strip on the OD of the flattened cone bit ..
but that's an arc. Only one tangent point at best if you try
to make one flat sheet from the two bits.

It's not developable otherwise.

HTH

 

That's sounds like the way I am going to make it in two parts. Then
flat pattern each and join in the burn program.

Thanks
Steve

 

Then you have two parts that can be formed & welded together ....

 

The goal of manufacturing is not to weld. Welding take an trained
person. Where as forming takes a person who can push a part up to a stop
and push a green button. The machine does all the work. Less labor is
good. If it takes labor companies send the job to China. You should
know that.

Steve
IE

 

Steve,

What if someone tells you CAD is unskilled labor, its just some person
drawing lines and arcs while the computer does all the work?

Or someone says Solid Modeling that's unskilled labor, its just a
person pushing buttons and a few mouse clicks while making pictures
and the computer does all the work?

Welding, forming and machining are ALL skilled labor and "you should
know that".

Tom

 

You cannot unfold/form this as described; it's not developable.
Better to control the geometry & weld (it has to be welded anyway,
right?) & skip that formed "flange" IMHO.

HTH

 

Are we thinking of clueless jb here?