Are vanda baskets just for vanda's?
 

I was going to build a vanda basket and put a an oncidium in it. I was wondering if that would work, because I am worried it won't get enough water. I was able to save a oncidium that I rotted all the roots and was hoping this would help.

Also, what other orchids will grow well in these.

Depending on what media you use and your watering regiment you could grow about any thing. But I have seen Stanhopea, Masdevallia and a few others that I cant think of right now. I see no reason that Oncidium would not do fine.

To expand on what NEB said - moisture is the key.

The container and the medium together determine what the orchid "feels" on its roots.

Using a bark mix as an example, if you fill a plastic or ceramic pot, a porous clay pot, and a basket with it - you will get three different moisture retentions.

A basket is just a drier, airier container. It can be used bare root like for most vandaceous orchids, or can be filled with the medium of your choice. For media that are small or granular (lava rock, LECA, etc) or that have small components (bark mix with perlite or charcoal), I line the basket with window screen first. This keeps the drainage and aeration, and most roots will grow right through the screen. I don't recommend sphagnum in a basket because it still stays wet long enough to rot the wood.

I grow almost everything in baskets, because I grow outdoors in Florida and can't control watering during the summer rainy season.I currently have several from the each of the vanda, cattleya, dendrobium, oncidiaum, and phaelenopsis alliances, as well as a couple oddballs- almost all are in baskets with varying (or no) media.

I use sphagnum and large chunks of charcoal. Summers are very dry here, and the moss helps. I don't put very much in though, just enough to cover the roots, and I use lots of charcoal.