I actually did make a conical tower, doesn't show in the photo. I cut a long 'V' down the side of the cardboard tube, and taped the seam with duct tape. Worked very well, and was very easy to make.

: Hi Gary,

: Just a thought for an alternate way to easily make the tower... I have not
: done this, but intend to the next time I build a skirt: Make two disks out
: of plywood, one the diameter of the bottom of the spray skirt tower, and
: one the diameter of the top band... assuming a conical shape. Screw each
: of these disks to a 2x4 piece, a little like they are forms on a
: strongback. Then use strips like we use in building kayaks to fill in the
: gaps. Glue or don't glue - your choice. This is a lot easier way to build
: a tower than using sheets of aluminum, cardboard or other ways suggested
: by the article. It allows a custom fitting tower, instead of a straight
: sided cylinder, and the whole thing does not take more than about 15
: minutes to put together.

: Rick