That sounds like a pretty good idea! It could be built so it could be set on a table top, or a seperate stand.
And big enough to be used for larger projects. If we were not worried about longevity, the enclosure could be done with plywood (cheap and easy enough to rebuild later) With silicon caulk sealing the corners. Or wood with sheet metal on the inside.
I'm attaching an image of the one we have at work, it's oversized for what we do but it has lots of room to move things around inside and it's a good size for lots of things. That's a 5 gal bucket of media on the floor for sizing and yeah Sean, that's how the ran the air in that room.
Nancy