redidriva Q

[Jim]

I've got a plasterboard wall with indeterminate gap behind and a wide, heavy-ish mirror I want to hang on two slotted supports fixed to outer sides of the mirror.

Does anyone know what the weight limitations on these redidriva fixings are - I would guess this mirror is about 40lbs in weight so I'm asking for 20 lbs per fixing.

Additionally, the screws that are then driven into the fixing itself will need to protrude by about 3-4 mm to catch into the slotted fixings on the mirror. Is this acceptable?

thanks for help.

[Jim]

....apologies...I had an additional concern that I forgot to mention. The plasterboard isn't that thick (sorry, only have a passing knowledge about these things) - I'd say about 12mm. Does that demand a particular length/diameter redidriva? The metal units in my local diy seem to be a similar size - about

30mm overall including the spikey thing at the end which traps the screw.

[Dave Liquorice]

Personally I wouldn't trust a redidriva but then I've never used 'em. It's based on plasterboard has naff all strength over a small area, they just don't "feel" right for use with serious loads.

I'd use the metal "plugs" that splay out multiple metal fingers behind the board thus spreading the load and holding the bit of plasterboard around the hole in compression. You do need some space behind the board though, take a look in the sheds for how much(*) space you need. Maybe have a little explore with a thin drill and bit of wire to probe the depth available.

(*) How Much! being the thought that went through my head this afternoon when looking at these things in Homebase. Pack of 5 for =A37.99 or something daft. Screwfix 12p each for 10 of the biggest...

[Jim]

thanks for response - it's like a desert out there for info on this, no data sheets - nothing that I can find. I decided to buy a pack of these things and experimented with a scrap of plasterboard. What little i've gathered suggested a pilot of 7mm (I did 6mm). Then it was a very positive drive into the board nice and tight and the redidriva face perfectly flush with the plasterboard face. I did find that trying to undo the screw that sits in the fitting causes the redidriva to turn also and that seems to mince the plasterboard up rendering the fixing useless. Other than that, they seem to be ok.