I am in the process of setting up a digital forensics lab for my organization and I thought it would be practical to have a self/rack on the wall where I could place the duplicator (TD2 to be specific) and use the shelf to clone or image suspect hdd or media. This will save space on my working desk and at the same time I could apply a custom made antistatic solution where I would "ground" the shelf using the ground/earth cable of the electricity circuit (for safety reasons I could use an 1 mega ohm resistor parallel with this grounding line).
I am thinking about a shelf long enough to fit the duplicator in the middle, surrounded by the two media (maybe 75 cm long) and I am tempted to use a bare wire shelf (much like the picture found from 
Apart from being able to ground the wire-shelf, it allows air to flow and it actually helps in cooling the media which helps with R/W speed of the media.
While discussing my idea with some colleagues they suggested it would be a hazardous enterprise as I would be constantly running the risk to short-circuit something in the hdd (either suspect or clean) and I should not venture into something so risky!
I can see the validity in their argument but I kind of liked my idea and I am not willing to dismiss it just yet.
I would appreciate if I would get some other ideas and opinion about the matter…
I partly agree with your colleagues that there is a shock hazard, but I think it is because the space between the grates is so large.
Perhaps a combination of materials like this
Take your metal shelf idea and add anti-static rubber roll mat material
That way small parts do not fall through and if you have a piece of equipment where the feet do not line up with the grates it will not tip.
Thanks Bithead for the reply.
I like your idea and I was kind of playing in my head with the idea of adding an antistatic mat on-top of the metal shelf. This will remove the hazard of a shock but it will also "take away" the benefit of ventilation of the hard disks. Maybe this is what it takes to make it safe and it is best to be safe than fast.
If you are particularly worried about ventiliation get a drive caddy with direct cooling. I tend to find drives either justify direct cooling, or don't have a tolerance that would be affected by 1 side on a mat.
Thanks Patrick for the reply.
The drive caddie was not really in my plans but maybe it could be a solution. I am planning to use "bare bone" hard disks with the duplicator. One will be the suspect disk (of course) and the other will be the clean disk on which I will make the image. In some cases, there may be a need for two images.
Even though the drive caddie is not something we were planning on buying, the "direct cooling" you mentioned got me thinking… I could probably use some pc fans (from recycled computers) in order to "cool" the area where the shelf will be placed.