Problem with shell

 From:  ed17 (ED17ES)
3884.1 
Hi...

I tried to shell various similar surfaces but I had problems with these ones. The way I made the surfaces was taking one curve, copying it and moving its control points, then y loft the two curves and thats all. I made it a lot of times and no problem, but with these two it takes forever to shell and it never ends. Thanks for your answers.
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