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Gary Coffman
 
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Default Sheet Metal project price question.

On Sat, 3 Jan 2004 17:40:55 -0800, "lane" lane_nospam@copperaccents_dot_com wrote:
"Gary Coffman" wrote in message
.. .
On Fri, 2 Jan 2004 13:53:12 -0800, "lane"

lane_nospam@copperaccents_dot_com wrote:
I will be making a drip shield surrounding an 18"x30"x1" fixture plate

using
304 SS in 20 gage. The shield will be at a 45 degrees angle all the way
around the plate up and away from the periphery. This shield will be

about 7
inches tall and hence will add 14 inches to the overall width and length

of
the plate.


No it won't. The length needed to rise 7 inches at a 45 degree angle is
9.898 inches (hypotenuse of a 45 degree triangle is sqrt(2) times the

rise).
So the total amount added to the length and width of the sheet will be
twice that, or 19.796 inches. This is important to know if you're

supplying
the material.

Also, if you want a rolled lip on the edge (good idea if you don't want
people to be cut on the sharp edge), you have to allow enough material
for that too. By eyeball, I'd say about half an inch for the rolled edge,
so add another inch to the overall length and width dimensions of the
sheet.

Gary


You are not understanding how I'm arriving at my figures. You are correct
that the hypotenuse means I would need more than 7 inches of material to
actually make it. But when looking at it the completed unit, since it rises
at a 45 degree angle, the over all length of the whole plate with applied
splash shield is 18" plus 7" plus 7" equals 22". Since it rises 7" that
means that it is going to overhang by 7 inches as well.


I understand that. What I was telling you is that the sheet you cut to
form the shield is going to have to be about 6 inches longer and wider
than that because of the geometry, and because you'll probably want
to roll a finished edge on the shield.

Gary