Zinc Plated Flat Connecting Plate 80 x 38 mm G-JM15
The G-JM15 Flat Connecting Plate
A flat plate is the oldest connector in furniture and still the one that gets used most on a repair. It needs no fold, no clearance behind the joint and no second operation: it lies on the face, spans the damage, and pulls the two sides together as the screws go in. This plate is 80 mm by 38 mm from 1.0 mm steel, which is thin enough to sit flat on a panel without showing a step and stiff enough to close a split.
The finish is yellow zinc, a chromate over electroplated zinc. It is the standard protection for this class of plate: it keeps the steel from rusting in a dry interior, it does not flake when a screw head is driven down on it, and it takes a scribe mark when a hole has to be transferred. The shade varies from plate to plate, which is a property of the chromate bath rather than a fault.
The Hole Pattern And Why It Is Laid Out This Way
| Figure | Value | What it decides |
| Plate length | 80 mm | reach either side of the joint |
| Plate width | 38 mm | two columns rather than one |
| Strip | 1.0 mm | sits flat, closes a split |
| Column spacing | 24 mm | spread across the width |
| Row spacing | 16 / 31 / 16 mm | long span across the middle |
| Holes | eight, two columns of four | four fixings each side |
Two columns of four holes is the pattern that lets the plate do two jobs at once. Across the joint, four screws on each side hold the two members in line. Along the plate, the wide gap in the middle, 31 mm between the two inner rows, keeps the screws away from the joint line itself, which is where the timber is weakest and where a screw splits the member it is meant to hold.
Where A Plate Beats A Bracket
A bracket turns a corner; a plate joins two surfaces that are already in line. That makes the plate the right answer wherever the corner is inaccessible, wherever the repair has to be invisible from the outside, and wherever the joint has to be pulled closed rather than simply held. A split drawer side, a cracked chair rail, a bed frame that has pulled apart at a glued joint: all of those are plate work.
The plate is also the cheaper part. There is one pressing operation and no fold, so the cost per fixing is lower than a bracket of the same strip, and on a repair where several plates are used the difference matters.
Closing A Split With A Plate
The order of work decides whether the repair lasts. Offer the plate over the split dry and mark the holes, then drill the two holes nearest the joint on each side first, not the outer ones. Driving the outer screws first closes the ends of the split and leaves the middle open, because the plate cannot bend the panel back along its whole length; working from the centre outwards closes the split progressively and the plate ends up flat rather than bridged.
Use a screw long enough to reach sound timber but not so long that it breaks through the far face, and put a washer under any screw that has to sit on a hole larger than its head. On 1.0 mm strip a screw head alone will dish the plate round the hole, and a dished plate will not pull the joint flat.
What These Are Called
Three phrases come in on enquiries and all three are this plate. A zinc plated mending plate is the trade term on a builder's merchant shelf, and it is what a buyer asks for when the plate is bought by size in a pack. A flat tie plate is the phrase used where the plate is tying two members together rather than repairing damage. A timber connector plate is the phrase used on the continent and in export markets, and it points at the same flat, punched part.
What none of the three carries is the hole pattern, and on a plate that is the figure that matters: an 80 by 38 plate with eight holes is a different part from an 80 by 38 plate with four. State the length, the width and the hole count together and the plate is specified.
Checks On Delivery
Four checks on a carton of plates. Flatness: lay a plate on a bench and press a corner, because a plate that has been stored on edge will bow and a bowed plate will not sit down on a repair. Holes: run a finger round each rim for a burr, which holds the plate off the panel. Sheared edges: a clean cut with no ragged corner, since the corner of a thin plate is where a crack starts. Finish: a continuous chromate with no bare grey patch, which is where rust begins.
Count the carton by size. Plates that differ by a few millimetres in length are impossible to separate once they are loose, and the difference only shows when the plate is offered up to the joint.
Choosing The Screw
Three things decide the screw: length, gauge and head. Length is set by the member the screw goes into, not by the thickness of the plate, and the rule on a repair is to reach at least as far into the sound member as the screw diameter, without breaking the far face. Gauge follows the hole: a screw that rattles in the hole will not pull the joint, and one that has to be forced will split the plate round the hole before it bites the timber. Head matters most on thin steel: a countersunk head sits flush and spreads its load through the countersink, a pan head sits proud and dishes the plate, and a washer under a pan head is the compromise when the hole is oversized.
Pilot holes are not optional on hardwood. Drill just under the core diameter, to the depth of the threaded part, and the screw will pull the plate down and hold. Skip the pilot on oak or beech and the screw will shear or the member will split, whichever gives first, and the repair will have to start again with a bigger plate and a moved hole.
A Drawer Side, Step By Step
The commonest job for this part is a drawer side split along the runner line. Take the drawer out and work on the bench, not in place. Close the split by hand and hold it with a clamp, then offer the plate over the split so that the middle gap in the hole pattern sits on the damage and there are two holes each side. Mark through the holes, drill the two inner pilots, drive those two screws and check the split is closed before any of the outer four. If it is not closed, back the screws off, clamp again and repeat: the plate will close a gap of a couple of millimetres and no more.
When the split has closed, fill the remaining holes and check that the drawer still runs. A plate on the inside of a drawer side takes up clearance against the runner, and a repair that closes the split but stops the drawer sliding is not a repair. Where clearance is tight, take the plate down in width on a linisher rather than moving it to a weaker position.
Plates In Flat Pack Furniture, And On Site
The same repair comes up on site as on the bench, and the sequence does not change: close the joint, hold it, mark through the plate, drill the two inner pilots first.
Flat pack carcasses are held by cam fittings and dowels, and when one of those fails the plate is the standard field repair: it spans from the failed hole to sound board and takes the load off the fitting that has pulled out. The limitation is board thickness. On a thin carcass panel the screw has to be shorter than the board behind it or the point will show on the outside face, and on a panel thin enough to leave no room for a fixing the plate is only practical on a joint that is not visible from either side. Say which screw size follows.
Where A Flat Plate Earns Its Place
- A split in a drawer side, where the plate spans the damage on the inside face.
- A cracked chair rail or apron, where the plate backs the joint out of sight.
- A bed frame that has pulled apart at a glued joint, where the plate ties the rail back on.
- A butt joint in a frame or a crate, where the plate is quicker than a bracket.
- A shelf that has split at a screw, where the plate moves the fixing to sound timber.
- A door stile or jamb that has been damaged at the lock, where a plate reinforces the repair.
- Wardrobe and cabinet carcasses assembled on site, where plates are used instead of blocks.
- A joint that has already been repaired once, where a longer plate reaches sound material each side.
Thin Steel, And What To Do About It
A 1.0 mm plate is thin, and that is deliberate: it sits flat on a face without showing a step, and it can be cut with a hacksaw and drilled with a hand drill on site. The price of thin is that the plate will dish under a screw head that is driven too hard, and that it will not straighten a member that has already warped. Where the joint has to be pulled a long way, use two plates rather than one and take the load on both.
Cut edges are the other thing to watch. A plate cut on site has a raw edge with no chromate on it, and that edge is the first place rust shows. Touch it up with a zinc-rich paint before the plate goes on, and the repair will outlast the furniture around it.
The G-JM15 plate is 80 mm by 38 mm from 1.0 mm yellow zinc plated steel, punched with eight holes in two columns of four, spacing 16 / 31 / 16 mm along the plate and 24 mm across. Packed to count by size.
Say what the joint is and how many fixings it will take, and the plate can be checked against it before anything ships. Other lengths in the same 1.0 mm strip are available on request against a drawing.
Comprehensive score