Difference between downspout crimper and duct/stove pipe crimper?

[Larry Dawson]

I'm redoing a couple of our downspouts to accommodate rain barrels. I can't find a downspout crimper locally. Guy at Menards insisted the duct/stove pipe crimper they have is the same thing. It appears to be the same as the Malco downspout crimper I found online, both are

5-bladed. In looking over Malco's site they have identical looking crimpers for both purposes. The difference I could find is in the throat depth, 31.8mm for the downspout crimper, 41.3mm for the round pipe crimper. That's a big difference in the lenth of the 'crimp'. Any opinions on whether the one I bought will work as well on the downspouts? Yep, I know, grab one and see, but I haven't cut or pulled any down yet, want to have all the stuff I need before I start.

Thanks for your help. Larry Dawson

[DT]

I use my duct crimper for downspouts, it works OK. It doesn't make the same kind of crimp as the factory, you will notice the factory downspouts have heavily indented corners which really helps them slide together. But it does the job and the downspouts fit together. It helps if you crimp next to the corner, then twist the pliers to help indent the corner. The longer length on the duct crimper makes for a more gradual taper and a tighter fit, I believe.

[Phisherman]

I can not recall where I saw the plans, but I made a metal crimping tool from three metal scraps and bolt/lock nut. Does an equal job as a $40 specialty tool and lasts forever. Great for metal ductwork or rainspouts. For downspouts I use aluminum rivets to secure them in place.