Measure from the door edge to the cup rim
Keep the edge distance and cup-center distance distinct. If K is 4 mm, the 35 mm cup center is 21.5 mm from the edge. If K is 3 mm, the center is 20.5 mm. These values follow from a 17.5 mm radius.
The official 110° reference brochure’s printed page 4 lists a 35 mm cup, a minimum 13 mm boring depth and B = 3–7 mm for the shown 71B3550 / 71B3650 / 71B3750 family. B is called K in this calculator. Check the exact model, fixing method and current drawing.
| K / B: edge to cup rim | Edge to cup center | Basis |
|---|---|---|
| 3 mm | 20.5 mm | K + 17.5 mm |
| 4 mm | 21.5 mm | K + 17.5 mm |
| 5 mm | 22.5 mm | K + 17.5 mm |
| 6 mm | 23.5 mm | K + 17.5 mm |
| 7 mm | 24.5 mm | K + 17.5 mm |
Check bore depth, remaining material and the frame
Measure the finished door thickness where the cup will sit. Subtract the entered bore depth to record the remaining material behind the cylindrical cup bore. That subtraction is not a minimum safe wall-thickness specification; include the actual cutter’s center point and the hardware drawing in your check.
On a frame-and-panel door, the cup must fit within the available stile and avoid the panel groove, rail joint and fastening zones. K plus 35 mm exceeding the entered stile width is a geometric conflict. Passing that width check does not verify screw holding, cup-wall strength or compatibility.
- Confirm the full hinge and compatible mounting-plate identifiers.
- Check cup depth, cutter tip, fixing pattern and specified door thickness.
- Inspect the back of the door, panel groove and rail joints at every cup.
- Use the actual template or jig instructions and a representative test piece.
Enter a planned hinge quantity; verify it with Blum
Weight, dimensions, material and hardware all matter. Measure the door including handles and attached hardware, then use the exact manufacturer selection chart. This page records the weight and dimensions but does not calculate a safe hinge count from them.
The count is your planning input. The position illustration spaces that many centers between equal top and bottom offsets. It checks that cups fit and do not overlap. This is a geometric sketch, not a manufacturer drilling template or a strength calculation.
A tall or wide front can need a different arrangement even when a simple weight example looks similar. If a chart’s boundary, model, material or installation assumptions do not match, resolve them with the manufacturer rather than rounding a result into a recommendation.
For n planned hinges, i = 0 … n−1:
yᵢ = end offset + i × (door height − 2 × end offset) / (n−1)
All y positions are measured from the same top edge.Frequently asked questions
How far is a 35 mm hinge cup center from the door edge?
The center is K + 17.5 mm from the edge, because the cup radius is 17.5 mm. K measures to the cup rim. Use the K / B range from the exact hinge drawing.
Is a 13 mm cup depth correct for every 35 mm hinge?
No. The cited 110° brochure specifies at least 13 mm for the shown 71B3550 / 71B3650 / 71B3750 family. Other models and fixing methods can differ. Verify the full drawing and actual door thickness.
Does this calculator recommend hinge quantity from door height?
No. You enter a planned count and measured weight. Manufacturer selection depends on weight including handles, dimensions, material and the actual model. The evenly spaced sketch does not establish load capacity.
Can the cup-center result determine mounting-plate height?
No. Cup-center geometry alone does not determine mounting-plate height, overlay or opening clearance. Use the exact hinge and compatible plate planning table.
Are the drawn holes a full-size drilling template?
No. The SVG is a schematic with listed dimensions. Use the actual hardware drawing, a suitable jig and a checked test piece. Do not drill by measuring a browser or print scale.
Sources and scope
- Blum CLIP top BLUMOTION 110° brochure — drilling diagram, printed page 4
71B3550, 71B3650 and 71B3750 reference family: 35 mm cup, minimum 13 mm boring depth, B = 3–7 mm. Other variants need their own drawing.
- Blum EASY ASSEMBLY — Number of hinges
Door weight including handles, dimensions and material affect quantity. This page does not turn a height measurement into a universal load rating.
Worked examples are calculations under the stated assumptions. They are not physical test results or manufacturer approval of a finished assembly.