Joint
Cut a woodwork joint where two boards overlap, such as a finger (box), butt, dowel, housing, rebate, mortise and tenon or halving joint.
- Joint JPart Studio toolbar
Joint cuts real woodwork joints for you. Model both boards full size, so they overlap where they meet. Joint cuts the joint out of the overlap and works out the sizes.
Board 1 is the board the joint is cut into, such as the side of a bookcase or the leg of a table. Board 2 is the board that goes into it, such as the shelf or the rail.
How to use it#
- Model the two boards full size, overlapping where they meet.
- Click one board, Shift-click the other, then click Joint or press J. With nothing selected, SchoolCAD picks the first two parts that overlap.
- Click the type of joint. SchoolCAD starts with a finger joint for thin sheets, and a housing or halving joint for thicker boards.
- Check Board 1 and Board 2 (goes in) in the lists. Click ⇄ to swap them. (For a finger joint they are Panel 1 and Panel 2.)
- Set the sizes, or keep the ones SchoolCAD fills in.
- Check the preview, then click ✓.
Joint types#
| Joint | What it is | What you can set |
|---|---|---|
| Finger | Fingers that lock together at a corner (a box joint), for laser-cut boxes. | Fingers: how many in total (an odd number looks best). Clearance: a small gap so the fingers fit (0.1 to 0.2 mm for the laser). Start with: which panel has the first finger. |
| Butt | Board 2 is cut back so its end sits flat against board 1. Hold it with screws, nails, glue blocks or brackets. | Nothing. |
| Dowel | A butt joint held by hidden dowels, glued into both boards. | The dowel size (Ø6, Ø8 or Ø10, and 30, 40 or 50 long), How many, and how far they go Into board 1. |
| Housing | Board 2 sits in a groove across board 1, like a shelf in a bookcase. At the end of board 1 it becomes a rebate: a step cut along the end. | Depth: a third of the thickness is usual, or half for a rebate. |
| Mortise & tenon | A tongue (the tenon) on the end of the rail fits a slot (the mortise) in the leg. The strongest frame joint. | Tenon thickness, Shoulders (how far the tenon is set in from each edge), and the Depth, or tick Through. |
| Halving | Where the boards cross, each loses half its thickness, so their faces end up level. For frames, cross rails and egg-crate dividers. | Top half: which board keeps its top half. |
Tips#
- Until you type a size, the box shows the size SchoolCAD worked out, and it changes when the boards change.
- The note under the sizes explains the joint, such as which dowels to buy and how deep to drill.
- Dowels are made as parts, so they appear in the cut list, the exploded view and renders. Untick Show the dowels as parts if you do not want them.
- A finger joint shares the overlap out as fingers, so the box keeps the outside size you drew.
- You can model a whole project with the boards overlapping, then add the joints at the end. Check lists every overlap, with a Make a joint button that starts a joint between those two parts.
- The assembly instructions use your joints to say how each part joins on.
If it does not work#
- These boards do not overlap. Model both boards full size so they overlap where they meet, then add the joint. Make board 2 longer, or move it, so it goes into board 1.
- Board 2 should be the one that ends at board 1 (the shelf or rail). Swap the boards. Click ⇄.
- Board 2 goes right through board 1. Use a halving joint, or shorten board 2 so it stops at board 1.
- The overlap is not a simple box, so the joint may look odd. Joint works best where two plain, square boards meet. Look for a cut or a rounded edge inside the overlap.
- The dowel holes nearly go through board 1. Use shorter dowels or a thicker board.