interior door handles - knobs to levers?

[IanJ]

All of the interior doors in my house are fitted with brass 'passage knobs', like this: http://www.locksonline.co.uk/acatalog/Knobsets__2_.html

They are all a bit old and knackered, and I want to replace them with some 'levers on rose', like this: http://www.charles-mason.co.uk/productselection.asp?product_id=2258

Problem is, the hole in each door to take the current knobs is 50mm diameter - almost the standard diameter of newer-style levers on rose (usually 50mm-52mm).

I'm trying to work out how I can fit the new levers without lots of faffing around with wood filler. Anyone done this kind of thing before?

 

[nstreet]

The spec states that the rose is 52mm. That's not the diameter of the hole that is required. It is probably the run of the mill square bar, approx 10mm. Your problem will be that there is nothing to fix the handle to, as you have a 50mm hole where the old fittings were. You will need to fill the hole with a block of wood, otherwise its a new door