How to make a dust bath??

I put the plastic box out filled with sand/compost and they just ignored it!  In the end I poured the lot into a corner of the run by a post where they seemed to be trying to do something there.  Two of the girls had filthy chests where I presume they were trying to bath?  Anyway, now with the snow on the ground I won't know if that worked or not! 

What type of sand can you use.... any?

mine just make their dust baths in the dirt wherever they want - usually where I am going to not notice and fall in  I did try providing them with a bath filled with building sand but they ignored it   

Well, after all my attempts to make them a dust bath they did exactly as most people said, they made their own!  I found them using a corner of the run next to a post and so added a bit more soil, sand mixture and I would say 3 out of the 5 use it.  I do need to find a way of keeping it a bit drier though as there is no cover on it at all.  They seem to enjoy it which is the main thing.

Don't think it has to be bone dry for them, just loose enough so that they can easily dig down into it, and get it between their feathers.

I've just sorted out my compost area, and have a huge mountain of lovely compost ready for the garden . . . or at least that was the idea.

The girls have comandeered it.  Dust bathing, digging, even a bit of tunnelling.  I'll have to get them some pit props so they can do a proper job.  Though the rats seem to manage well enough without   They're back.  Time to get the Eradibait out again.