Working with fibreboard

1. MDF is prone to splitting along edges but repairs easily.

2. Force glue into the crack while the screw is still in place.

3. Remove the screw after injecting glue into the crack.

4. Clamp the damaged area to complete a flaw-free repair.

5. Seal porous MDF edges by rubbing in drywall compound.

Bolt it up

MDF works well for making jig parts that aren’t under a lot of stress, especially jig bases. This material can be drilled and tapped to accept bolts, which is useful for knock-down jig assemblies. Predrill correct-sized holes for coarse-threaded bolts from 1/4″- to 1/2″-diameter; use a drill to run a metalworking tap into and out of the hole. Use a countersink bit to remove frazzled fibres at the top of the hole, then install your bolt.