Hob cut out

Sandtree

So this is the manufacturer's diagram...



I was a little confused by the superscript +3 and so called them and they said it means there is 3mm tolerance meaning the width can be 500-503mm but they seemed a little confused so I thought I'd ask here... I've always seen tolerances as a plus or minus value before. 

BUFF

assuming that the hob is 500x780 you can't have a minus tolerance on a cutout though - the hob wouldn't fit if the hole is too small. 

FaceHead

It is more usual to express a tolerance as +/- as you suggest, but sometimes there's a good reason for thinking about it as x+y or x-y.

In this case, I imagine the hob is a rectangle that is 500 x 780 (or a fraction less), and then there's a lip that sits on top of the worksurface. So the cut out needs to be at least 500mm so the hob drops in, but not too much bigger so that the lip drops through too. 

You could call it 501.5 +/- 1.5, but that's not really what's going on: 500+3 makes more sense. 

Sandtree

But we agree that the +3 is supposed to be the tolerance? As I say the person seemed unsure

I am a little surprised that an induction hob is held purely on the glass but that bit is certainly "correct"

BUFF

what is the make/model of hob?

grumbler

Sandtree said:

But we agree that the +3 is supposed to be the tolerance? As I say the person seemed unsure

I am a little surprised that an induction hob is held purely on the glass but that bit is certainly "correct"

It is the tolerance. And, yes, it's normal when it sits on the glass.

FreeBear

Sandtree said: I am a little surprised that an induction hob is held purely on the glass but that bit is certainly "correct"

Fitted an induction hob for niece just before Christmas (Cooke & Lewis). it drops into the cutout and is held in place by a couple of spring clips on each side.