In letterpress, lockup is the process of assembling  a jigsaw puzzle of rectangles around the type to lock it all in place, with the ultimate goals of (a) having it not fall out while on the press and (b) having all the type level, so that it gets inked evenly and prints uniformly. 

The pieces of this jigsaw puzzle, beyond the type, are a mixture of wooden and metal furniture, mixed with properly-sized-to-the-type metal spaces of varying widths. 

In a not-completely-outfitted shop like mine, lockup  can be particularly challenging, due lack of diversity and quantity of furniture, but lockup is always challenging anyway. 

Here’s a photo of my lockup for one side of the February This Box is for Good box. This was, indeed, challenging, as space was at a premium, yet the specific distance between LOVE and FOOD needed to be exact, and BE THE needed to be centred under FOOD. I’m proud that I managed to pull it off, even if it is a little Frankensteinian.