What stock to store for mill/lathe work?

[Cory]

For us this is a totally loaded question as we've probably used 30 different sizes of stock so far this year, in addition to a bunch of stuff we have stocked that we haven't used yet or have used in the past.

This is what we've purchased this year:

Size Length Alloy Quantity
.090"x48"x144" 6061-T6 1
1"x1"x.125" Tube 24' 6061-T6 4
1"x1"x.063" Tube 24' 6061-T6 7
1"x2"x.125" Tube 24' 6061-T6 3
1"x2"x.063" Tube 24' 6061-T6 6
.75"x.75"x.063" Tube 24' 6061-T6 3
.5"x.5"x.063" Tube 24' 6063-T6 2
.063"x1" Bar 12' 6061-T6 2
.125"x3" Bar 12' 6061-T6 2
.125"x4" Bar 12' 6061-T6 4
.125"x2" Bar 12' 6061-T6 2
.125"x1" Bar 12' 6061-T6 1
.1875"x2" Bar 12' 6061-T6 2
.1875"x3" Bar 12' 6061-T6 1
.1875"x4" Bar 12' 6061-T6 2
.25"x2" Bar 12' 6061-T6 2
.25"x4" Bar 12' 6061-T6 2
.25"x6" Bar 12' 6061-T6 1
.375"x1" Bar 12' 6061-T6 1
.5"x1" Bar 12' 6061-T6 1
1" square bar 12' 6061-T6 1
1"x.25" bar 12' 6061-T6 1
1"x1.25" bar 12' 6061-T6 2
1.25" square bar 12' 6061-T6 1
1.5" square bar 12' 6061-T6 1
1.25"x2" Bar 12' 6061-T6 1
1.25"x3" Bar 12' 6061-T6 1
2"x4" Bar 12' 6061-T6 1
.750"x.063" Tube 24' 6061-T6 3
1" x.063 Tube 24' 6061-T6 3

We also commonly use 1" round bar, 2.25" round bar and a bunch of other rectangular barstock sizes.