Bobsim - you don't say where your queens are coming from - so - if it'll help: when making increase by 'walk-away' splits, it's important to ensure that the splits are large enough to have the necessary size of workforce to raise a reasonable quality queen. You can also reduce their workload by feeding, and by supplying pre-drawn comb.
One good method of ensuring you have an adequate number of bees in the box is to fill it with nurse bees, which are far less likely to abscond then foragers as they've not yet ventured outside of their home, and so have no bearings with which to 'return home'.
A good method of selecting nurse bees is described by Larry Connor in several of his online .pdf articles. The links for these collections are:
http://www.wicwas.com/American_Bee_Journalhttp://www.wicwas.com/Bee_CulturePerhaps the quickest introduction to this technique can be found in BC2012-07.pdf which he's entitled as: 'Making Doolittle's Nucs'.
Essentially, the method involves removing a couple of brood frames from your target 'donor hive', shaking the bees off, then placing those frames in a nuc box placed above the donor hive with a QX between them. After a short period, the brood frames will be covered by nurse bees which have ascended up through the excluder. At this point the nuc box can be removed and placed in it's new location, with the assurance that the vast majority (if not all) of those bees will then stay put.
LJ