How To Create a TV Unit

How do you build a timber TV unit?

This is a step up from a weekend shelf: a routed, housed-joint cabinet in pine with a plywood back and bun feet, assembled with Selleys Aquadhere Interior and no visible fixings across the front. The technique that makes it work is the routed channel — each upright sits in a shallow trench cut into the panel above and below it, so the joint locates itself and the glue only has to hold what gravity and geometry have already positioned.

The single most useful habit in the whole project is the dry fit. Every stage is assembled without glue first, checked for square and for flush joints, adjusted, and only then taken apart and glued up. Aquadhere Interior is a PVA wood adhesive that has to be clamped or tapped home while wet; there is no version of this build where you discover a mis-cut after the glue is on and recover gracefully.

What you need

2 × pine panels — 1800 mm × 450 mm × 18 mm (top and base)
4 × pine panels — 310 mm × 450 mm × 18 mm (uprights)
1 × pine panel — 650 mm × 450 mm × 18 mm (shelf stock)
1 × plywood — 2400 mm × 1200 mm × 10 mm or thinner (back)
6 × bun feet
1 × 500 mL Selleys Aquadhere Interior
1 packet of 25 mm wall panel nails, and 6 × 8 × 45 mm screws
Router and router bit, 18 mm or smaller
A straight edge longer than 450 mm, and two F or G clamps
A sharp chisel or utility knife, a square, a hammer or mallet, and sash clamps
A damp cloth for glue squeeze-out

Marking and routing the channels

Mark the divisions. Take one of the full-length 1800 mm panels and mark the centre of its length at 900 mm. Measure and mark 320 mm either side of the centre mark, then a further 500 mm out from each of those.
Mark the channel width. Place one of the 310 × 450 pieces on the marked line and draw a line either side of it, using a square to keep it true. That marks out the channel to be routed.
Set up the router. Set the cutter depth to 6 mm. Clamp your straight edge in position so the cutter is aligned to the inside of the pencil marking. With a smaller router bit you will need two or more passes.
Check the fit. Insert the 310 × 450 piece into the channel to make sure the cabinet cheek fits. Better slightly snug than loose — a snug housing carries the joint; a loose one leaves the glue doing all the work.
Repeat for the other three division marks.
Line up the second panel. Once one panel is routed, position the other full-size panel next to it lengthways. Line up the ends, then clamp a straight edge long enough to span both pieces so the router can continue each rebate across into the new panel.
Use an offcut as a register. Place a piece of waste panel, or the 310 × 450 piece, into the slot across the two panels. This keeps the remaining cuts aligned. Continue the previously routed channels across into the new panel.
Check all eight. Once all eight channels are cut, test the fit with the 310 × 450 piece and set the panels aside.

The shelf supports

Rout the shelf housings. Select two of the 310 × 450 pieces to serve as shelf supports. Measure down 90 mm and rout a channel across the panel, using the same router settings.
Stand them up. Position these two panels upright in the middle slots of the panel you have chosen as the base, with the two shelf rebates facing inwards and the channels on the top side. Stabilise the uprights and check they are at 90 degrees to the base.
Measure and cut the shelf. Measure the distance between the bottoms of the two shelf slots, transfer that measurement accurately to the 650 mm panel, and cut it to size.

Dry fit, then glue up

Dry fit the whole cabinet. Place the two inside supports into the middle rebates, slide the shelf into its rebates, position the two end supports in the base, then place the top panel and push it down onto the uprights. Check for squareness all round and for flush joints. Make any adjustments now, then disassemble.
Glue the centre assembly. Glue the shelf into the two middle supports with Aquadhere Interior, wiping off any squeeze-out with a damp cloth. Remove every trace — residual glue inhibits staining and finishing later. Set it aside, keeping it square.
Fit the end supports. Glue and fit the two end supports onto the base. Tap them home with a sacrificial piece of wood and a hammer or mallet.
Fit the centre assembly. Repeat with the centre piece, shelf in position, and the other end panel.
Fit the top. Apply Selleys Aquadhere Interior to the top of each upright and place the top panel. Tap it home with sacrificial wood and a mallet. Wash off excess glue with a damp rag. If any joints are loose, hold them with sash clamps — making sure each upright is square — until the glue has set.

The back panel and feet

Size the back. Measure the outer edge height and width of the unit and subtract 5 mm from each. Cut the plywood or backing material to those dimensions.
Turn the unit over. Rest the face side on the bench, protected with a blanket or something soft. Use masking tape on the back to mark where the internal supports run, so you can nail accurately.
Glue and nail the back. Apply a thin bead of Selleys Aquadhere Interior to the rear frame of the unit. Line the bottom edge of the back panel up with the bottom of the base — this leaves a slight gap at the top of the unit, which is desirable. For extra security, hammer thin wall nails in approximately 400 mm apart over the frame. Turn the unit so it is lying on its top.
Attach the feet. Apply a bead of Aquadhere Interior to the inner section of each foot. Place the feet into position, using a piece of scrap wood as a gauge to set them one thickness in from the front and side edges.
Set the rear feet differently. On the rear or unseen side, the feet sit right on the edge of the base. On the front, leave an 18 mm gap to the edge so the feet are less visible.
Screw if needed. You may find it necessary to secure each foot with a screw through the centre. If you do, choose a screw length that will hold the foot without exiting the top of the panel above.
Let it set. Allow the unit to sit until the glue has set, then move it into position.

Working with Aquadhere Interior

Aquadhere Interior is a PVA-based wood adhesive designed for interior woodworking — furniture assembly, cabinet making and similar indoor bonding. The two things that matter most on a cabinet this size are both procedural rather than technical.

Wipe every trace of squeeze-out while it is wet. This is called out twice in the build sequence for good reason: dried PVA seals the timber surface, and stain or finish will not penetrate through it. A smear you cannot see on raw pine becomes a pale blotch the moment stain goes on, and by then it is under the finish.

Clamp or tap the joints properly closed. The method uses a mallet and a sacrificial block to drive housed joints home, with sash clamps as backup for anything loose. PVA needs the joint faces in contact; it is a gap-filling adhesive only in the loosest sense, and a housed joint that is not fully seated will show as a line across the front of the cabinet.

For comparison, Selleys' exterior-grade Aquadhere is clamped for 30 minutes on softwoods and 1 hour on hardwoods, with the joint left unstressed for 24 hours and maximum strength attained in 24 hours — longer in cold, damp conditions or with dense timbers. Pine is a softwood, so if you want a working rule for how long to leave the sash clamps on before moving to the next stage, that is the closest published guidance Selleys gives for the range.

Limitations — where Aquadhere Interior should not be used

Interior use only. It is not water resistant.
Not suitable for exterior projects — use Selleys Aquadhere Exterior, which is weather resistant, for anything outdoors.
Not for wet or damp areas.
Not for structural applications.

For a TV unit in a living room, none of these are constraints. They matter if you were thinking of adapting the design for a verandah or a laundry, where the exterior-grade adhesive is the correct product.

Common questions about building a TV unit

How deep should the router channels be?

Set the router cutter depth to 6 mm.

Should the uprights fit tightly in the channels?

Yes — better a bit snug than a loose fit. Test the fit with a 310 × 450 piece before routing the rest.

What size do I cut the back panel?

Measure the outer edge height and width of the unit and subtract 5 mm from each measurement.

How far apart should the nails in the back be?

Approximately 400 mm apart over the frame, with masking tape on the outside marking where the internal supports run.

Why does the back sit flush at the bottom rather than centred?

Lining the bottom edge of the back panel up with the base leaves a slight gap at the top of the unit, which is the intended result.

Why does it matter so much to wipe off the glue?

Residual glue inhibits staining and finishing. Dried PVA seals the timber, and stain will not take over it.

How long do I leave the clamps on?

Until the glue has set. Selleys' published clamping guidance for the Aquadhere range is 30 minutes for softwoods and 1 hour for hardwoods, with the joint left unstressed for 24 hours.

Can I build this for an outdoor or covered area?

Not with Aquadhere Interior, which is not water resistant and is for interior use only. Aquadhere Exterior is the weather-resistant product in the range.

Do I need to screw the bun feet on?

You may find it necessary to secure each foot with a screw through the centre. If you do, pick a screw that will not exit the top of the panel above.

How do I keep the cabinet square during glue-up?

Check for squareness at the dry-fit stage, keep each sub-assembly square as it is set aside, and use sash clamps on any loose joints while making sure each upright is square.

What if a joint is loose after routing?

Hold it with sash clamps until the glue has set. A snug housing is better, so check fit before routing all eight channels.

Can I use a thicker plywood back?

The specification is 10 mm or thinner. A heavier back adds weight without adding much to a cabinet that is already braced by its housed joints.