How to roll a cone with apex smaller than the rollers?

I went overboard last summer and bought a 36" sheet roller with solid 3" rolls. ($100). Not a slip roll. It’s so heavy, I can barely lift one end.
I have done a couple of things on it, including a cone to act as a plenum over a small blacksmiths forge. But that cone has a 6 inch opening at the apex, so no problem.

As soon as I got that roller home and realized that it wasn’t a slip roll, I started obsessing about needing one. So, a month or so ago, I found an old Niagra 36" slip roll with 2" rollers and bought that one, too. Not telling you how much I paid for that one. (Very heavy, too!!!)

Anyway, now I can make cones and tubes down to 2" diameter, but what it I wanted to make a cone with a pointed apex; eg; no hole at all at the end. Or even a cone with a 1" apex diameter, as in the GEK cyclone separator. How does one roll such a thing?

To make our cyclone separator, we cut the sheet metal shape in half and made a series of bends in the brake press to get half a shell, then welded the two halves together, but that seems like the long way 'round.

Pete Stanaitis

Hi Pete;
Wow, I purchased a 36" Niagera slip roll with 2" rollers also, about 60 years old I guess. Funny you brought this up as I am having trouble rolling the cone. Like you said, you can’t get a 1’ hole with 2" rollers, so I made a 2" hole at the bottom and will reduce it down to 1". I have a press brake also and that’s how I made the cover arund my second cyclone to make the preheat for the nozzles. That’s before I got the slip roll.
Just thought it funny you posted this now. I did not want to buy a cheap Chinese slip roll so I paid $800.00 for the Niagera and damn well worth it.(AMERICAN MADE). Dan

yeah thats an issue. I built that little roller we have with 1" rolls. Its crude and ugly but that little thing has taken the abuse and will roll 14 ga. cones down to a 1" apex. But it has seen its better days and I bought the materials to build another one. This time I will need to send it out to be machined. Im simply going to copy our big roller. It will have solid 1" rollers that I will need a machine shop to machine the ends for me. The side plates are 1"x 6 HR flat bar. Im planning on just using brass bushings on the ends of the rollers with fitted pillow blocks.

Right now time is an issue so this project is on the back burner for now. Now that we have the CNC machine on line Im spending most of my time cranking out parts on it. Wish I had that thing two years ago, that thing is awesome.

I bought and still have this roller I got off ebay. Its not stout enough to do what I need it to do. When I got this I took it out of the box tried to roll some 14 ga sheet with it and then put it back in the box. lol. Thats where its been ever sense. If you are interested in it send me on offer, Im sure it will do as advertised on the ebay listing below but do not expect any more from it.

Here is a listing on ebay that is like the one I have.