Grohe shower mixers holes

[Bill]

Large shower mixer holes.

What do you guys use to cut these holes as i have to do this week that has a 158ish hole and the cover plate is extremely tight.

Thanks in advance.

 

[Waluigi]

That’ll be a Grohe Smart control then with that Dimension.

Draw around the white cover that comes with the Rapido back box and then cut out with a grinder a millimetre or two away from the edge and then use a vacuum brazed finger bit to get to the line.

Yes I agree that the Grohe valves don’t leave much margin for error. Especially the Square Shrouds.

 

[Bill]

Square it is too. I will order a finger bit then.

 

[Old Mod]

I’ve a 120mm electroplated drill bit, I know it’s not big enough, but it slices thro porcelain and you’re straight in to the middle of your hole with grinder to open it up.
For the cost (anything from £23 ) I find it faster and less risky.

 

[Waluigi]

You can buy 150mm hole saws. Might be worth looking into.

I’ve always managed without the larger hole saws but I agree that it’s probably less risky. It’s time consuming going full at it with a grinder IMO.

 

[Italy]

finger bit
same a waluigi

 

[Bill]

finger bit
same a waluigi

Ordered one from @ATSDiamondTools today.

 

[Bopster]

I’ve a 120mm electroplated drill bit, I know it’s not big enough, but it slices thro porcelain and you’re straight in to the middle of your hole with grinder to open it up.
For the cost (anything from £23 ) I find it faster and less risky.

That’s exactly what I did on my last Smart shower. Used the 120 then just ground out the hole with a large hole cutter

 

[macten]

This is when my rotozip comes out

 

[Time's Ran Out]

This is when my pin hammer and pinchers come out.