The Hoffmann Frame Joiner is perfect for joining hard wood picture frame mouldings. The joiner routes a slot for a Hoffmann dovetail key. Getting a tight seamless join on dense hard woods such as oak and walnut can be a struggle on an underpinner because underpinners displace timber fibres as the v-nail is inserted. If you make a lot of frames with harder wood moulding then the Hoffmann Frame Joiner is a great alternative because it works completely differently to an underpinner, by routing a slot for a dovetail joining key. Once Hoffmann dovetail keys are tapped into place, the corners are pulled tightly together. The Hoffmann joiner is especially useful for getting a great join on tall, narrow mouldings. The robust construction of the machine means it’s perfect for higher volume work.
How does the Hoffmann Frame Joiner work?
Set the router depth according to the size of key. Position the slot and lay a piece of mitred moulding on the bed and line up the slot location with the indicator on the machine. Slide up and lock the centre fence plate. Place the mitred frame moulding to be routed on the left side of the bed with the rebate facing away. To start the machining cycle of the Hoffmann, pull the lever. Padded hold-down plate clamp secures moulding and motor is switched on. Continue pulling the lever to advance the router head until pre-set height is reached. Release the lever to return the router to its home position, shut off the motor and release the moulding. Move the mitred piece to the right side of the bed to rout the other end. Repeat for all four mitred pieces. When all four mitred pieces are routed at both ends, taps the keys into place with a soft hammer.