[Shop-talk] Sheet metal question

[Drew Rogge]

I assume the box is steel? You might be able to make a plywood template with
a 7-1/2 dia hole in it and use a router with a flushtriming bit to auger out
the hole. I'm sure it would ruin the bit and be quite noisy but if it's a one
time deal?

Drew

On 06/03/2013 08:53 AM, Robert Bender wrote:
> I have a ridiculously old bead blast cabinet that works fantastically well.
> The gloves clamp to a 5-1/2 inch diameter flange, and are now wearing out.
> None of the blast supply places seem to have this size of glove.  They will
> all sell gloves that fit a 7-1/4 inch flange.  Some even sell the retrofit
> flange.  So, I am thinking about how to cut two clean, accurate circles, 7-1/2
> inches in diameter in a box made of 14 gage sheet metal.  I don't have access
> to a plasma cutter here at home, my nibbler isn't capable of handling the
> thickness, it can't be disassembled to fit into the mill and my Greenlee
> knockouts don't go anywhere near that big.  I suppose I could buy a 7-1/2 inch
> hole saw, but Google shows $112 and up for something that will likely get used
> once. I'll probably end up borrowing Dad's tanks and cutting torch, but that's
> a hassle to transport and will require a fair amount of clean up of the cut
> edge.  Any neat out-of-the-box ideas
>   while I talk one of my buddies into buying a plasma cutter that I can
> borrow?
> Bob