Sheet Metal Corner Rounder

[Reloader1776]

I am in search of tool to put small radiused corners on my sheet metal projects. Nipping the corner off at a 45 works, but doesn't look very professional, and rounding with a grinder is time consuming.

Does someone make either a handheld radiused snip or maybe a set of dies I can put in my arbor press that will create a nice 1/8" or so radius for my pieces up to 16 GA? I've been trying to find one online, but don't even know what it would be called. So far I've only found ones for paper or thin plastic. I can't be the first person that's ever wanted a tool like this.

 

[francist]

I searched “corner rounder” and got quite a few different makes and qualities. Here’s one…

 

[GeneT45]

Search for "notcher". 16ga is tough though, at least on a budget. Seems that there's a big price jump between 18ga and 16ga.

GsT

 

[Reloader1776]

Search for "notcher". 16ga is tough though, at least on a budget. Seems that there's a big price jump between 18ga and 16ga.

GsT

Are there any notchers that do outside corners? All the notchers I've ever seen or used are for cutting an inside 90.

 

[Reloader1776]

I searched “corner rounder” and got quite a few different makes and qualities. Here’s one…

View attachment 502831

That would be a nice unit if it didn't cost as much as my stop shear! Maybe somebody makes just the punch and die so I wouldn't have to pay them for the arbor press too.

 

[GeneT45]

Are there any notchers that do outside corners? All the notchers I've ever seen or used are for cutting an inside 90.

There are some with dies available to do about anything you'd do with a corner. We had one (and a bunch of dies) where I used to work. I priced one out and it was not practical for me. If you're in a tool-rich environment you might get lucky on the used market though.

GsT

 

[RJSakowski]

It would be fairly simple to make up a punch and die for your task. The die would be made from a cylindrical section of an appropriate diameter. The punch would be a cylindrical tube, the inner diameter matching the desired radius The actual punch would be ground away to create the 90º arc. The remaining o.d. of the cylinder would be used as the guide for the punch. Use O1 for the punch and die and harden and temper appropriately.

The punch and die could be set up for an arbor press but given the relatively small radius, a lever operated setup could be used.