[bobcowan]

If possible, use all standard/imperial or all metric. If you mix them, you'll end up carrying two differant tool sets. it's a real pain.

I have a whole drawer full of nuts and bolts. There's another bin on the other side of the garage that's been collecting fastners for decades. And there's more scattered around in the basement. I know where all of these fastners are, and can find them pretty easily. And, I have a pretty good idea of what's where.

BUT..... every time I do a project, it seems like I do not have that special fastner that I need. I end up at the hardware store anyway.

My advise is to keep a box of the most common sizes around, and don't waste time and money on the rest. For example, I keep #10, 1/4", 3/8" fastner sets on hand - bolt, lock nut, flat and star washers. I generally stock 1" bolts/screws. I rarely need anything longer. And if I need anything shorter I can just trim it down.

If you try and keep everything on hand that you might need, you'll end up with a hardware store in your garage. Sounds pretty cool, but gets expensive, difficult to maintain, and takes up a lot of room.