How to join a frame

Different mouldings require different components to enable them to be joined into a picture frame. Timber mouldings are most commonly joined by inserting a thumbnail wedge or V nail into the timber from the underside of the moulding.

In the past mouldings have been joined with numerous components including nails, biscuits and wooden splines.

Metal mouldings require specific angled plates which allow the mitred corners to be screwed together.

Plastic mouldings of the solid type can be joined using V nails and a plastic adhesive. Plastics of the extruded section type are joined using hardware similar to aluminium joining plates or by a spring type clip.

Composite frames if of a timber base can be joined by conventional methods.

Materials:

PVA glue
"V" nails
Hammer
String Clamp
Frame pieces
Wax crayon

	Step 1: Roughly assemble your frame face up on a flat surface to check that it looks right. Apply PVA glue to the mitres.
	Step 2: Assemble your pieces and place the string clamp around the outside of the frame. Pull the string on the clamp until it is tight and the frame is pulled together.
	Step 3: Make any adjustments in the corners of the frame and then pull the string firmly ensuring the cord locks into the wedge on the clamp.
	Step 4: Turn the frame over and insert the "v" nails by hitting them from behind with a hammer. Note: You must hit the "v" nail from behind otherwise it may compress and not enter the moulding correctly. Make sure that you put the "v" nail in the thickest part of the moulding with the sharp side downwards against the moulding.
	Step 5: When all the "v" nails are in place you can remove the clamp. Clean off any excess glue from the joints. Fill any imperfections in the joints with a putty or a wax crayon of a suitable colour.