Frequently asked questions about single pivot hinges
- Why do I need single pivot hinges?
- Are there any disadvantages with single pivot hinges?
- Where should I utilize single pivot hinges?
- How to adjust the hinges?
- What kind of finishes are available?
- Do single pivot hinges made of stainless steel exist?
- Where should I take special attention?
- How to get the optimal positioning of the hinges?
- Why is the third screw so important?
- How can I check the correct application of the hinges by the craftsman?
- Why do the single pivot hinges require more precise working?
- What about the work facilitating measures like quick mounting and eccentrical adjustment?
Why and where is it necessary to take single pivot hinges? What are the main benefits?
They are flat – the hinge arm component is only 5-7 mm thick. Therefore they take less space and all drawers or other inserts can be easily built in.
They provide large openings – from 180° to 270° with full door overlay. This facilitates the access to the interior of the cabinet.
Furthermore, no damages through big door openings can occur. Owing to the 270° opening angle no leverage damages will take place even in cases where the doors were opened unintentionally vigorous.
Single pivot hinges are more stable than the concealed hinges and are especially goog for heavy duty cabinets. They consist of less single pieces, f.ex. they have only one axle or pivot (that’s where their denomination comes from).
This axle is considerably stronger and longer as the one of concealed hinges. The twin version has only one hinge arm (middle component) on which two doors are mounted (on each side one). For storage wall cabinets this signifies substantial cost savings.
Are there any disadvantages with single pivot hinges?
All things in life have their price. It might therefore come out that you will be less appreciative on some issues such as:
The visible knuckle. As only one axle is available it must be positioned outside the cabinet and thereby allow the door to turn around it. The visible knuckle can be disguised, f.ex. when black knuckle is combined with black carcass edges.
The necessity of higher precision. A piece with less components means that tolerances for imprecise work are reduced. It could therefore happen that 3 single pivot hinges mounted with axles not being in line will not move.
Where should I utilize single pivot hinges?
I In all those cases where the usage is high, f.ex. hospitals, schools, laboratories, dressing rooms, swimming pools and cubicles.
How to adjust the hinges?
Mostly in 2 dimensions. Contrary to the concealed hinges the single pivot hinges are equipped only with vertical and lateral adjustment. The reason for that is the fact that in order to achieve the maximum stability the cranked hinge arm has to lie firmly on the inner surface of the carcass and its edge. Only in case of inset doors the depth adjustment is possible and makes sense because in this case the hinge arm lies firmly only on the inner side of the carcass.
Why do I need Grade 1 single pivot hinges?
Differently to the private area school children, students as well as personnel in clinics and restaurants handle the furniture less than careful. Not only are the doors being opened more frequently, they have to bear higher loads and one tends to lean upon them…
That’s why the world wide hardest standard comes into play: the ANSI/BHMA Grade 1. In the West of the USA hinges and other materials prior to be used in public houses and buildings have to be graded with Grade1 by Woodworking Institute of California (WIC). It proved to be a reliable recommendation, so that some other States in the USA as well as many architects require Grade 1 for public projects.
BUT check carefully the product you are choosing. You will find hinges which met the Grad 1 test on the express condition that the vertical adjustment has not been activated. Make sure that the product you have chosen is certified in full and entire accordance with the Grade 1 standard including the adjustment options. Ask the supplier to present you a written confirmation or check the COMPLETE text of the test results (not only the title page on which usually the restrictions are not mentioned).
What kinds of finishes are available?
The standard finishes are nickel (the most frequently taken), black (f.ex. for the purpose of disguising the knuckle) and brass (is less frequent, might cause longer lead times).
Do single pivot hinges made of stainless steel exist?
Most probably you require the single pivot hinges made of stainless steel for a MRI room or for an environment where aggressive media affect the furniture. There is a hinge made of stainless steel in the Prämeta portfolio and it is conceived for application with HPL panels, which equally have been developed for such applications.
Where should I take special attention?
Cut off dowels
Cups with dowels reduce fixing time. However, for doors with laminated surface the pre-drilled hole for the dowel has to have a 45° chamfer. Otherwise the dowel angles will be cut off by the sharp edges of the laminate and thus reduce the stability of the cup fixing in the door. The surest way to solve this problem is to take cup without dowels and fasten fix them with screws.
Damages through leverage
Even small forces charging the outer edges of the door can easily be increased through the leverage effect, so that hinges or wood can be damaged. This danger exists when concealed hinges with an opening between 90° and 180° are taken.
This issue does not arise with single pivot hinges because they have an opening angle of more than 180°. If at the end of a storage wall cabinet you have a corridor passage it would be reasonable to take a full overlay application with 270° opening in order to avoid the leverage damage.
With respect to leverage corners can also be the cause of damages. In such cases opening restrictor should be taken in order to limit the opening of the door and thus avoiding the collision of the door with the corner.
Clothes can be caught inside the single pivot hinge. To avoid it, cloth protection straps which the manufacturer of the hinges can supply, should be applied.
How to get the optimal positioning of the hinges?
Do not position the 3 hinge exactly in the middle of the door.
In case a door requires a third hinge it should not be positioned exactly in the middle. There it will fulfil only the guiding function which could be enough for a thin panelled door. But thicker doors should have the third hinge positioned above the middle position. In this case the hinge can guide the rotation of the door and in addition to it hold the door weight, thus supporting the upper hinge.
Additional hinge on the upper door end
When a door needs a 4th hinge or a smaller but heavy and/or wide door needs a 3rd hinge, this hinge should be placed right next to the top hinge, both as high as possible to the door’s top. That is the best position to hold higher loads.
Why is the third screw so important?
The third screw on the hinge arm is very important. It is to be placed AFTER having completed the adjustments when the cabinet was mounted in place. Then it will not only lock the adjusted position of the door but also give stability to the whole system. If you forget to put the third screw the lever forces working on the other two screws will be about 9 fold of what they were working on the third screw – and this will probably cause claims from the customer.
How can I check if the craftsman did mount the hinges correctly?
Traces of the fixing screw head
First check whether the hinge arm was correctly mounted with the hinge cup in the door. With screw mounting versions you can check it easily because if the screw was sufficiently tightened it’s pan head will leave visible traces on its counterpart. If you can’t find that, most probably the mounting was done with a wrong screwdriver or bit type and / or the screw gun was not correctly hold and pushed. If the fixing screw was not tightened good enough, the system cannot work properly and this particular craftsman was the producer of the claim.
Placement of the 3rd screw
Is the third screw in place at al hinges? If not see for consequences at Why is the 3rd screw so important? So once again the mounting craftsman was causing the trouble.
Spacers for doors which are thinner than 19 mm
If you use panels slimmer than 19 mm, especially together with the full overlay hinges, the outstanding part of the hinge arm may cause problems. If you put two of those cabinets side by side, they will press each other up to bending the arms and the doors will not work properly. This is why you should use transparent spacers which are neutral in the appearance but ensure the correct setting of the hinge.
Why do Institutional Hinges ask for more precision in execution?
Institutional Hinges provide more strength for cabinets in rougher environments compared to concealed hinges. There are less parts, e.g. only one single pivot But stronger design with fewer parts also means less tolerance for non accurate work. So e.g. mounting 3 Institutional Hinges not in correct alignment may result in the door not getting moved.
What about more comfort like quick mounting and cam adjustment?
The fewer parts you use, the less tolerance in the whole system and the stronger the connection So for Grade 1 applications like Schools, Hospitals, Restaurants you should prefer screws on versions towards clip versions.
Comfort in adjustment
Adjustability is necessary to enable the craftsman for a proper setup on the spot. In the same time, every adjustment means possible weakening of the system. So design has to be respecting the high demand of stability for Institutional Hinges. Some products loose Grade 1 certification when using certain adjustments (Why do I need a Grade 1 Institutional Hinge?).