Cold Rolled Steel Folding Door Hinge Kit G-K437a

The G-K437a Folding Door Hinge Set, Complete And Fitted

Six of the eleven frames in this folder are used on this page and the first one is the whole set, which is the honest place to start with a fitting sold as a kit. Laid out are two hinge arms in cold rolled steel, an aluminium track running between them, two small four-hole fixing plates, two threaded cover caps, two nylon sliders and a screw pack. A folding door hinge is never bought as a single hinge: it is bought as the arm pair, the track the arms run on and the fittings that hold the door leaf, and this frame is that list. The rest of the page then does three things with the remaining frames. It reads the technical drawing for the figures. It shows the two hinge arms on their own, which is where the pivot and the slide can be seen properly. And it shows the set fitted to a wardrobe and to a corner cabinet, which is what this hinge is for.

The reason a folding door hinge earns its place in a cabinet is space, and it is worth stating plainly because it is the whole argument. A normal cupboard door of any width sweeps a quarter circle when it opens, and the radius of that circle is the width of the door, so a door 600 millimetres wide needs 600 millimetres of clear floor or clear air to swing into. A folding door hinge splits the leaf so the door folds back on itself and then travels on its own track instead of swinging out. The door of a corner unit, a wardrobe that stands beside a bed, a cabinet in a narrow galley kitchen or a unit whose front is blocked by another door can all be opened with a folding door hinge where a plain hinge has nowhere to go. That is the job this set does, and the frames of it fitted show the same thing twice on two different pieces of furniture.

The Figures The Drawing States

The drawing is headed unit mm and Material Cold rolled steel, and it carries the hinge arm in two views. Along the arm the plate is marked 265 millimetres overall. At the mounting end the plate is 72 millimetres wide with 58 millimetres between the fixing centres, and the arm is offset 18 millimetres from the plate edge with 39 millimetres marked to the pivot and 11.5 millimetres to the end of the plate. Across the body the drawing gives 50 and 50.5 millimetres as the two overall heights, 33.5 millimetres and 30.5 millimetres as the step between them, and 20 millimetres as the plate width. In side elevation the arm rises to 80.3 millimetres at the raised end and stands 73 millimetres at the other, which is the profile that carries the door leaf clear of the cabinet side. The one slotted feature on the drawing is labelled an adjustable screw hole and marked 4 by 9 millimetres, and that slot is what allows the arm to be set to the door after the cabinet is built rather than before.

Two of those figures are the ones that decide whether the hinge fits a cabinet that already exists, and both are stated here because they are easy to leave off a quotation. The first is the 265 millimetre arm: it is the length of travel the hinge takes up inside the cabinet, so it sets the minimum internal depth behind the door and it is not a figure that can be shortened on site. The second is the 80.3 millimetre rise at the raised end of the arm, which is the clearance the hinge needs above the door leaf as it folds. A cabinet whose internal height is tight against the door will not take this hinge however well the footprint reads on paper, and the two figures are therefore put side by side rather than buried in a drawing note.

The Two Arms And What Moves On Them

The gallery frame with the pair of arms on their own is the one that explains the mechanism, and it is worth following because a folding door hinge is two motions in one fitting. At the door end of each arm there is a mounting plate with four holes, and that plate is screwed to the door leaf. Between the plate and the arm body there is a pivot, so the arm swings relative to the leaf. At the cabinet end the arm runs on the track that ships with the set, and the slider that sits in the track lets the folded leaf travel sideways along the cabinet front. The result is the two-stage motion every folding door has: the leaf folds back on the pivot first, then the folded leaf slides along the track, so the door ends up stacked beside the opening rather than standing out in front of it.

The arms are handed, which is the detail that catches out a first order. One arm carries the pivot on its left and one carries it on its right, so a set is a pair rather than two of the same part, and the frames of the two arms show them mirrored to each other. A buyer counting parts for a run should count pairs and not arms, because two left arms will not make a folding door, and a replacement arm ordered on its own has to be ordered as the same hand as the one that failed. This is a small point on paper and a costly one at the packing bench, so it is worth confirming the pair in the order rather than assuming the carton holds two identical hinges.

The Track, The Caps And The Screws

The aluminium track is the part that makes the second half of the motion possible, and the frames show it twice: once as a bright multi-channel extrusion and once with the white capping profile that closes the visible face of it. The track is screwed to the cabinet top or to the underside of the shelf above, and the sliders on the arms run in it. The white capping profile is not a separate product; it is what the track looks like once the face is closed, which matters on a wardrobe where the track is on show above the doors and a bare aluminium channel beside a white carcass reads as unfinished. The two threaded cover caps in the set close the screw heads at the arm plates, and the screw pack covers the track, the plates and the caps on one door.

What the accessories frame proves is that the set is complete for one door, which is the question a trade buyer actually asks before ordering forty. The count on the frame is two cover caps, two nylon sliders and a screw pack; the screw pack is the only part of the set whose count is not readable off the photograph, so the number of screws per set is a packing figure and is confirmed on the packing list rather than on a picture. The caps are threaded rather than push fit, which is the better of the two on a fitting that is cleaned and knocked in a wardrobe, and the sliders are a nylon part running in an aluminium channel, which is the combination that stays quiet and does not gall the track as a steel-on-aluminium slider would.

The Two Frames Of It Fitted

Two frames show the same set doing its job on two pieces of furniture, and between them they answer the question a plain set of product shots always leaves open. The wardrobe frame shows a tall door folded back beside its opening with the arms at the top, the middle and the bottom of the fold and the track running vertically down the folded edge, so the door stacks into a narrow slot instead of standing out into the room. The corner cabinet frame shows the opposite arrangement: a cabinet with its door folded back into the cabinet mouth, opened far enough to reach the appliance inside, with the two arms visible on the cabinet side wall. Both are the same hinge doing the same two-stage motion, and both are situations where a quarter circle swing is not available.

The fitted frames are worth a second look for the mounting pattern rather than for the furniture. In both, the arms are fixed along the vertical edge of the folded leaf rather than across its face, and the track runs on that same edge, which is why the leaf folds flat instead of hinging out. That arrangement is the one the drawing supports: the 265 millimetre arm, the 72 millimetre plate with its 58 millimetre centres and the 4 by 9 millimetre adjustable slot all belong to a hinge that is fixed along an edge. A cabinet whose door has to fold across its face needs a different fitting, and it is better to know that from the drawing than from a returned carton.

Where A Folding Door Hinge Earns Its Keep

A folding door hinge is bought for four kinds of job and they are worth naming. It goes on the corner unit of a kitchen or a living room cabinet, where the front returns on itself and a swinging leaf would foul the adjacent run. It goes on a wardrobe standing close to a bed, a wall or a door, where there is no clear floor for a swing. It goes on an appliance garage or a tall larder whose door has to open flat and stay out of the working space. And it goes on any cabinet whose front is part blocked, which is the common case in a fitted room where the layout is right and one door is wrong. In all four the hinge is chosen because the leaf has to end up beside the opening rather than in front of it.

Because a bi-fold door hinge travels rather than swings, it also changes what the door has to be. A folding leaf is usually two narrow leaves joined at the fold rather than one wide panel, so the door weight is split and the hinge carries less than a single wide leaf of the same total width. That is a benefit on a tall wardrobe door where a single leaf would rack, and it is a consideration on a short cabinet where two narrow leaves look busier than one. The tracks and the arms in this set are sized for the leaf in the frames rather than for an unlimited panel, so the door size for a given set is a drawing question and is answered from the drawing and the packing list, not from the photograph.

Questions A Fitting Buyer Asks

A kit like this is bought on a handful of questions, so the hinge is answered question by question here, and each answer points at the frame or the drawing it comes from.

• What is in the set? Two cold rolled steel hinge arms, an aluminium track with a white capping profile, two four-hole fixing plates, two threaded cover caps, two nylon sliders and a screw pack, as the kit frame shows.
• How long is the hinge arm? 265 millimetres, marked on the drawing, and that figure is the travel the hinge takes up inside the cabinet.
• How high does the arm stand? 80.3 millimetres at the raised end and 73 millimetres at the other, so that is the clearance the hinge needs above the leaf as it folds.
• What is the mounting pattern? A 72 millimetre plate with 58 millimetre hole centres, 18 millimetres in from the plate edge, with the pivot at 39 millimetres.
• Can the hinge be adjusted after the cabinet is built? Yes, through the 4 by 9 millimetre adjustable screw hole, which is the slotted feature on the drawing.
• What material is the hinge? Cold rolled steel, stated on the drawing, with the track in aluminium and the sliders in nylon.
• Are the two arms identical? No, they are handed, so a set is a pair and a replacement has to be ordered as the same hand.
• Where is this hinge used? Corner units, wardrobes close to a wall or bed, appliance garages and any cabinet whose door cannot swing a quarter circle.
• Does the door fold or slide? Both, in sequence: the leaf folds on the pivot first, then the folded leaf travels along the track.
• How many screws come with a set? The screw pack is in the kit frame but the count is a packing figure, confirmed on the packing list rather than on the picture.

Fitting The Hinge Set In The Right Order

A folding door hinge set goes on in a fixed order and the order is part of why a fitted pair works, so the sequence is set out here. The hinge track is fixed to the cabinet first, at the height the hinge arm needs above the door leaf, because the track is the datum every other part of the hinge follows. The hinge arms are then mounted to the door leaf on their four-hole plates, and the leaf is offered up to the track with the sliders already in the channel. The hinge pair is adjusted last, using the slotted screw hole on each hinge plate to bring the leaf square in the opening, and only then are the cover caps pressed onto the hinge plate screws. Fitting the hinge arms to a leaf that is already hung, or setting the hinge adjustments before the track is final, is the usual reason a folding door rubs at one end.

The hinge pairs on the leaf are the second thing to get right, and the frames show why. Each hinge arm has one pivot and one sliding end, so a fold needs a hinge pair working against each other: the upper hinge carries the fold at the top of the leaf and the lower hinge carries it at the bottom, and the two arms of each hinge pair face opposite ways. Where a tall leaf uses three hinge positions, as the wardrobe frame shows, the middle hinge pair keeps the fold straight between the outer two rather than adding load to them. A hinge set fitted with both arms of a pair facing the same way will fold once and then bind, which is a fitting error rather than a hinge fault, and it is worth checking the hand of every hinge pair before the screws go in.

The hinge track also decides how much of the cabinet front the door occupies when it is open, and that is a planning figure rather than an installation one. A folding leaf stacks beside its opening, so the hinge track has to run at least the width of the folded leaf beyond the opening it clears, plus the small allowance the hinge sliders take at each end. On a corner unit the two hinge runs meet at the corner and the allowance is shared, which is why the corner frames show the leaf folding into the cabinet mouth rather than beside it. Measuring the hinge track from the opening rather than from the cabinet edge is the mistake that leaves a door unable to open fully, and the hinge cannot correct it afterwards.

How A Bi-fold Door Hardware Set Is Specified

A bi-fold door hardware set like this one is specified from four numbers rather than from a catalogue description, and each of the four comes off the drawing or the cabinet. The first is the hinge arm length, 265 millimetres here, which sets the internal depth the hinge needs behind the leaf. The second is the hinge arm rise, 80.3 millimetres at the raised end, which sets the clearance the hinge needs above the leaf. The third is the hinge plate pattern, 72 millimetres across with 58 millimetre centres here, which has to suit the leaf the hinge pair is going onto. The fourth is the hinge track length, which is a per-cabinet figure rather than a hinge figure and is agreed with the order. A bi-fold door hardware set that matches on all four fits; one that matches on three is a return.

The hinge material is the fifth question and the easiest to answer from the drawing, which states Cold rolled steel for the hinge arms. Cold rolled steel is the right hinge material for this fitting because the hinge arm is a long pressing that has to hold its profile: a hot rolled strip would need more finishing to reach the same flatness, and a hinge arm that is not flat rocks on its plate instead of sitting on it. The hinge track is aluminium, which keeps the run light above a wardrobe door, and the hinge sliders are nylon, which is the part that runs rather than the part that carries. Three materials, three jobs, and the hinge arms are the loaded part of the set.

Who Supplies This Hinge

This folding door hinge set is supplied by Guangzhou Gorgeous Intelligent Technology Co., Ltd., a furniture and architectural hardware business whose range covers hinges, drawer slides, handles, stays, legs, castors, locks and the connecting plates that go with them. The company works to export orders: quantities, packing, carton marking, barcodes and shipping documents are agreed before production rather than after it, and the specification a buyer writes on the order is the specification the factory works from. Handed pairs, the track length for the cabinet and the screw count per set are all parts of that specification.

Ordering

Send the model number G-K437a with the number of sets, the track length required and the hand arrangement if the pack is not the standard pair, the carton marking you want and the destination port, and confirm the internal depth and the height above the leaf against the 265 millimetre arm and the 80.3 millimetre rise at the same time. Samples are available before a production order so a set can be fitted to the buyer's own cabinet and the door folded and run through its full travel, which is the fastest way for both sides to agree that the travel suits the cabinet and that the pair is handed as ordered. The drawing, the packing list and whatever test documentation we hold for G-K437a are issued on request, and delivery and payment terms are agreed order by order on the proforma rather than assumed from a previous order.

Hinge Settings Worth Checking Before Handover

The last pass on a folding door is a hinge pass, and it takes a few minutes per door. The hinge pairs are checked for hand, the hinge plates are checked for square against the leaf edge, and the hinge track is checked for level across its whole run rather than at the ends. Each hinge is then run through its full travel with the door on it, because a hinge that is smooth when the door is light can bind once the leaf is loaded. The slotted screw on each hinge plate is the only adjustment on this fitting, so any hinge that will not sit square after that adjustment is pointing at the leaf or the track rather than at the hinge.

• Hinge pair hand checked before the first screw goes in, so the two hinge arms of a pair face opposite ways.
• Hinge plate square to the leaf edge, because a hinge plate set on the skew pulls the fold out of line.
• Hinge track level along its whole run, not just at the two ends the hinge sliders travel between.
• Hinge travel run with the leaf mounted, since a hinge that is free unloaded can bind under load.
• Hinge slot left free to adjust, with the cover caps on the hinge plate screws only after the setting is final.
• Hinge screws seated flush under the caps, because a proud screw head on a hinge plate catches a cloth.
• Hinge track ends clear of the cabinet side, so the hinge sliders reach their full travel without a stop.
• Hinge arms clear of the cabinet interior fittings through the whole fold, checked by folding the door once slowly.
• Hinge count per leaf recorded against the drawing, so a three-hinge leaf is not packed as a two-hinge set.
• Hinge carton marked with the hand and the track length, because a hinge set that is right but unmarked becomes a return.