callouts for features before bending

[Dwight]

All

I have a sheet metal part with holes on a bend, cut or punched round before bending. I figured I'd add "BEFORE BENDING" on the hole call-out, but maybe there's a standard call-out I don't know about?

Dwight

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[Ronan]

I add the hole callout information to the flat pattern.

[Dwight]

We let the vendor do the flat pattern.

[mme]

There is a requirement to open them and their distance to the wall.

[TTevolve]

I don't know of any standard call outs for that.

I would make the assumption it has to be done before bending though if nothing was specified since it's very hard to put a hole in unless it was being machined after, but that's uncommon on a sheet metal part.

[Dwight]

Okay, thanks for considering it. I'm fine with what I have and am moving on. As you noted, the cut or punch will be done before bending.

Dwight

[DLZ_SWX_User]

In our shop, 99% of the holes in our sheet metal parts are cut with the laser & are in the DXF. No prints, so no call outs for laser cutting unless the customer request a print. Any machining and/or holes that need to be threaded are assumed to be done prior to bending and are included in the bend print drawings for our shop unless specified different.

But once again each shop has different requirements. Here most of our parts are custom one off parts. Our few production pieces that we do make, usually have more detailed drawings, but normally hole sizes are not called out if laser cut.

[Dwight]

DLZ

Most of our sheet metal vendors work from a model for cutting and bending, and depend on a drawing for the material and for inserts. For us, a drawing is always needed for first article inspection and product monitoring.

Dwight

[jcapriotti]

Most of our sheet metal vendors work from a model for cutting and bending, and depend on a drawing for the material and for inserts. For us, a drawing is always needed for first article inspection and product monitoring.

Yeah, I was wondering about inspection. @DLZ_SWX_User if you don't have a drawing of the final part, what do you inspect by?

[retonny77]

Adding "BEFORE BENDING" makes it clear. We always stick to detailed drawings for inspections, it helps avoid confusion later.

[DLZ_SWX_User]

Yeah, I was wondering about inspection. @DLZ_SWX_User if you don't have a drawing of the final part, what do you inspect by?

Since we have our own laser and most of our parts are cut in house, the fellow running the laser usually verifies the part with the DXF file he receives. The DXF file name includes part number, material type, thickness, and quantity needed. For us 9 times out of ten if the part has the wrong size holes, it was wrong before the laser ever cut it. We do have drawings for Bending, Machining, & Welding, just not Laser cutting. Sorry, maybe I should've left my 2 cents out earlier!

[jcapriotti]

Since we have our own laser and most of our parts are cut in house, the fellow running the laser usually verifies the part with the DXF file he receives. The DXF file name includes part number, material type, thickness, and quantity needed. For us 9 times out of ten if the part has the wrong size holes, it was wrong before the laser ever cut it. We do have drawings for Bending, Machining, & Welding, just not Laser cutting. Sorry, maybe I should've left my 2 cents out earlier!

So, I guess in the case of the DXF being wrong and you laser cut it, when would you discover it was cut wrong? For us, the flat would've been inspected with a print before committing to further down stream process. We wouldn't check against the DXF since that may be the root cause of the issue. The user may have had the wrong settings or scaled the DXF wrong....we've had that happen where we cut a part at 80% its actual size.