manual metal punching

HI everyone, I have a kind of unique process I need advice on. We use aluminum L channel 0.0787 thick that has a spot in one area that requires a punched out "notch" on one leg roughly 1.5" x 3". Currently this is done with a saw and it is rough and not at all consistent. I am looking for a manual machine that would be able to accomplish this cleaner. something like a shear/punch that would roll cut the rectangle into the material? Thoughts? Power is an option but the volume does not warrant an expensive machine.

Perhaps you could start with a notcher like this, and modify it to cut on three sides:

Baileigh SN-F16-FN Manual Corner Notcher | Baileigh Industrial

Summit1997 said:

HI everyone, I have a kind of unique process I need advice on. We use aluminum L channel 0.0787 thick that has a spot in one area that requires a punched out "notch" on one leg roughly 1.5" x 3". Currently this is done with a saw and it is rough and not at all consistent. I am looking for a manual machine that would be able to accomplish this cleaner. something like a shear/punch that would roll cut the rectangle into the material? Thoughts? Power is an option but the volume does not warrant an expensive machine.

Click to expand...

What if you made a punch and die and use an arbor press? Considering it's just straight lines you need to cut and you're able to get by with a saw right now, I don't think it needs to be anything fancy, especially for thin aluminum. I, personally would try welding pieces of carbon steel together into the shape you need for the die, then cut a piece of plate to shape for the punch. Weld of piece of tube to the back of the die and drill and tap it for a set screw to hold it to the arbor press.

Sent from my SAMSUNG-SM-G891A using Tapatalk

You say "L channel". Is that an angle with TWO sides or a channel with THREE sides? That difference could influence what tooling is used.

That being said, if the volume was not too high, I would be tempted to use chassis punches. Chassis punches are available in square and rectangular sizes. I have square ones up to one inch square and somewhat over one inch in a rectangular one. They produce nice edges that only need a bit of deburring. You must drill holes in the center for the draw bolt. I have used two and four smaller bites to achieve larger rectangular holes. The edges of the multiple punches can be aligned using the edges of the punch itself and this can leave an edge with no visible bump in it. When I use multiple punches I often use the slug from the first one to even out the forces on the punch in the second punch operation.

If your part allows the die side of the punch to be inside the "aluminum L channel" then you can use a heavy duty drill to power the operation.

I have routinely used these chassis punches in 1/8" aluminum and they will also do up to 3/16 but I use a cutting oil for those heavier gauges.

Greenlee is a good brand to look for. Used chassis punches are a frequent item on E-bay and they are easily sharpened. If you want to save time look for the "slug buster" style. Removing the slug on the older styles is a PITA that can take a minute or two.

Summit1997 said:

HI everyone, I have a kind of unique process I need advice on. We use aluminum L channel 0.0787 thick that has a spot in one area that requires a punched out "notch" on one leg roughly 1.5" x 3". Currently this is done with a saw and it is rough and not at all consistent. I am looking for a manual machine that would be able to accomplish this cleaner. something like a shear/punch that would roll cut the rectangle into the material? Thoughts? Power is an option but the volume does not warrant an expensive machine.

Click to expand...

It sounds like the OP wants a normal "Coper" attachment, like on an ironworker.

digger doug said:

It sounds like the OP wants a normal "Coper" attachment, like on an ironworker.

Click to expand...

That's what my first thought was, an iron worker, but he said he didn't want to invest in an expensive machine. I think a press would be cheaper and I don't think the tooling would be hard to make. Maybe I'm wrong, though.

Sent from my SAMSUNG-SM-G891A using Tapatalk

52 Ford said:

That's what my first thought was, an iron worker, but he said he didn't want to invest in an expensive machine. I think a press would be cheaper and I don't think the tooling would be hard to make. Maybe I'm wrong, though.

Sent from my SAMSUNG-SM-G891A using Tapatalk

Click to expand...

You could get just the attachment, IIRC Cleveland tool steel sells one in a die set, set it
up in a simple arbor press.

digger doug said:

You could get just the attachment, IIRC Cleveland tool steel sells one in a die set, set it
up in a simple arbor press.

Click to expand...

Heck, if someone already makes a decent punch and die set with the right profile, that'd be the way to go. I just assumed they were trying to get some unique or otherwise uncommon profile.

Sent from my SAMSUNG-SM-G891A using Tapatalk

52 Ford said:

Heck, if someone already makes a decent punch and die set with the right profile, that'd be the way to go. I just assumed they were trying to get some unique or otherwise uncommon profile.

Sent from my SAMSUNG-SM-G891A using Tapatalk

Click to expand...

I forgot to mention Vogel tool & die:
Pipe notchers, tube notchers, tube cut off tools - Made in USA!

Cleveland, scroll to very bottom, looks similar to OP's request:
Products: Die Sets, Blades, Custom and Replacement Parts, Connectors and Brackets | Cleveland Steel Tool