Hi,

To be clear, 79T959 is for the door in the extension,

sl 1-4 means that the slack must be between 1 and 4 mm to work properly.

if you look at the instructions, the base must be at a fixed distance of 21.5 mm from the edge of the side.

The 35mm hole has a fixed distance of 8mm from the side edge.

i.e. (35/2)+8 = 25.5mm to axis from Side edge

many people make the mistake of thinking that the value of 3-7 is random, 

this value depends on the slack!

-With a 1 mm slack, this means drilling 7 mm from the edge of the door.

-With a 4 mm slack, this means drilling 3 mm from the edge of the door.

If you set slack of 8mm you can see drilling is flush to panel

If you set slack of 4mm it left only 3mm and with 2mm edge, it left only 1 mm from door edge..

The mechanism is similar on a classic hing

the fixed distance is the 11mm overlap from drilling from inner side

the drilling position is therefore (35/2)-11= 6.5 

with 3-7 this means that the overlap is 11+3-7= ol 14-18

that is to say a slack with a cheek of 18mm which should be between 0 and 4mm maximum.

Adjusting a 7mm slack will ensure that the drilling is perfectly flush with the edge of the door, and polyboard takes this into account perfectly.

If you do this, you’ll be able to complete the adjustment with the set screws without reaching the end of the adjustment process and having hinges that malfunction or wear out prematurely.

Other example from hettich sensys

APPlied hinges, (full overlay), 

the fixed distance is the 12.5 mm overlap from drilling from inner side (equals to 11 with standard blum)

BIN hinges, (inset) 

The 35mm hole has a fixed distance of 4mm from the side edge.

Make caution datasheet always provided with Bplate with thickness of 0mm

To ensure correct slack in our libraries, the sensys hinges use a 3mm thick base.

the thickness value is indicated in our libraries with I00 or X00

I is for an aligned base
X is for a cross base

followed by the thickness ’03’.

for example from libraries “Hettich/hing.Sensys-X03/bin/ba52/sl 1-4”

must be mounted on a 3 mm thick base plate

Of course, it is possible to duplicate, edit and move the forging by a few millimetres within the limit of the adjustment screw.

but this will mean that you will have to work with the adjustment screws, with the risk of being at the end of the adjustment.

Hope that’s helpful, Alexandre