How do I make a frame and panel door?

A wide solid door would cup and split. A frame and panel door does not, because the frame is made entirely of narrow long-grain members which barely move at all, and the panel inside it is held only by grooves it is free to slide in. Once you understand that, every detail of the construction follows logically.

What you'll need

• Timber for stiles and rails
• A panel — solid timber, plywood or MDF
• A means of cutting mortise and tenons
• A router or plough plane for the grooves
• Clamps, glue and a flat assembly surface

Step by step

1. Cut the stiles and rails oversize and let them settle.Machine them roughly to size, leave them a few days, then bring them to final dimension. Timber often moves as internal stresses are released, and it is better that it happens before the joints are cut.
2. Groove the inside edges of every frame member.A groove down the inner edge of both stiles and both rails, the same width and depth throughout. This groove receives the panel and also receives the haunch of the tenons.
3. Cut mortises in the stiles and tenons on the rails.The tenon thickness matches the groove width so the tenon can run straight into the groove. Haunch the outer corner of the tenon at the top and bottom rails so the haunch fills the groove where it runs out at the end of the stile.
4. Fit each joint individually and mark it.Firm hand pressure to assemble, hands to take apart. Number each joint; they fit their own partner.
5. Size the panel to be loose across its width.Measure groove bottom to groove bottom, then take a few millimetres off across the grain so the panel has room to expand. Along the grain it can be a closer fit, because it does not change length.
6. Raise or rebate the panel edges if the panel is thicker than the groove.A raised panel is bevelled around its edges so a thick centre reduces to a tongue that fits the groove. A flat panel in thin material simply drops in.
7. Finish the panel before assembly.Essential. An unfinished panel that shrinks in a dry winter exposes a strip of bare wood along the edge, which is obvious against the finished face. Finish it fully first.
8. Dry assemble the whole door and check it.Diagonals for square and a straightedge across the frame for twist. A door that is twisted at glue-up is twisted forever, and it will not sit in its opening.
9. Glue only the frame joints.Glue in the mortises and on the tenons. Not a drop anywhere near the panel. The panel floats.
10. Clamp square and flat on a known flat surface.Clamps across the width at each rail, checked for square by diagonals and for twist by sighting. Correct before the glue grabs.
11. Fit the door to its opening after the glue has cured.Plane the edges for a consistent gap all round, hang it, then adjust. A frame and panel door is fitted like any other door once it is made.

Tips

• Small rubber or foam space balls dropped into the groove before the panel goes in centre the panel and stop it rattling, while still letting it move. They are cheap and they solve the one nuisance of a floating panel.
• A plywood or MDF panel does not move and can be glued in, which stiffens the door considerably — a legitimate choice for painted work.
• The tenon haunch is not decorative. Without it, the groove runs out at the end of the stile and leaves an open slot; the haunch fills it and stops the rail twisting.

Common mistakes

• Gluing or pinning the panel in the frame — The panel changes width and the frame does not. Glued, the panel splits or it pushes the frame joints apart. This is the whole reason the construction exists.
• Fitting the panel tight in the grooves — It has nowhere to expand in a damp season, so it forces the frame apart at the stile joints. Leave several millimetres across the width.
• Finishing the door after assembly with a bare panel — The panel shrinks in the first dry season and reveals an unfinished stripe along each edge, which cannot be finished afterwards without dismantling.

Questions people ask