If you are still looking for a source for milk crates while andymark gets them in stock, try MilkCratesDirect.com
They have a good deal on sets of 6 in a variety of colors, We got Orange
http://www.milkcratesdirect.com/set-of-6-square-milk-crates
shipping is fairly quick and these are the exact size needed.
we also got our crates from them so a quick warning. The covers will be really tight on them.
We got eleven of thesefrom Home Depot. About the same cost as the official crates, but no shipping costs. The ones we got were the same size as the one in the KoP. (We actually got them a lot cheaper because we used a couple of $25 HD donation coupons to buy them.)
We paid $8.88 each at Home Depot here. Just waiting for covers now…
I know that they are an official source just pointing out that the covers will fit very snug.
But are they stronger?
I’m not sure if you actually read the note in the update. There are two varieties of the crate. FIRST uses the smaller. If you get the bigger, the cover will be tight or not fit.
We bought several crates from Home Depot but ended up buying more crate at The Container Store. The weight of the home depot containers was about .6 lbs lighter than the official one. The ones from the container store were .3 lbs lighter while having the same dimensions. Just keep that in mind when sourcing your cubes that it is important to weigh them.
Or put a cup of milk (or other half pound weight) in the light ones.
and secure it.
A moving CoM will cause issues.
Evenly layer the milk so that the weight is uniform around the cube before securing it.
