Okay, then, here is the not-nice looking chart:
Tau Manta
Width 52 metres > assume width of 75 metres needed
Lenght 32 metres
Height 8 metres
Manta launch bay Model size Real life size factor:
Width 3,5 mm 75,00 metres 21,42857143
Height 1,5 mm 32,14 metres
Protector
Width 82 mm 1.757,14 metres
Lenght 40 mm 857,14 metres
Height 11 mm 235,71 metres
Custodian
Width 100 mm 2.142,86 metres
Lenght middle 55 mm 1.178,57 metres
Length launch 73 mm 1.564,29 metres
Height 25 mm 535,71 metres
Emissary
Width 58 mm 1.242,86 metres
Lenght 50 mm 1.071,43 metres
Height 14 mm 300,00 metres
Castellan
Width 37 mm 792,86 metres
Lenght 21 mm 450,00 metres
Height 3,5 mm 75,00 metres
Warden
Width 26 mm 557,14 metres
Lenght 20 mm 428,57 metres
Height 3,5 mm 75,00 metres
Here is the much nicer link:
https://docs.google.com/spreadsheets/d/1iI5tiCltviMHJz89N9peVb6uJWHaKg9jdFaiixf8zZE/edit?usp=sharingAnd some more background information:
Back in the day when we were debating the Tau forgeworld models and what there stats would be a hotly debated thing was the fact on which weapon on the model represented what. So...... I mailed the original forgeworld designer back then, who replied within a day!, to ask what his intention was.
So the stubs on the front, one on each wing, four next to the torpedo tubes, are the Railgun Batteries. The Large Turrets on top of the wings (1 per side) are the Ion Cannon. The small turrets all over are anti-ordnance (covering all arcs as the Tracking-System rules tell us). The Bay underneath is for Manta's and the holes in the front of the wings for shuttles, dropships and alike (barracuda's).
With above in mind Distant Darkness was created. The railguns stubs promoting fixed arc and leading to 90* turns. I am diverting...
So, if the designer says the launch bay underneath is for Manta's then we can assume he kept things on the model within scale of itself.
Above values may seem low compared to the FFG Rogue Trader ones. But they are quite perfectly in line with the old line of sizes that had Imperial Cruisers at 2500-3000metres long, light cruisers around 1000-1500metres, Frigates ~750metres and destroyers ~500metres.
All before Black Library started doing their stuff. And before FFG made Rogue Trader. I really love RT and Koronus (I helped on it, its got my name hey hey) but the sizes are still a quirk to me.
So, Frosty and everyone else. I hope above helps. And when translating to Rogue Trader just slap some metres on to them.