biscuit jointing
Biscuit Jointing offers an efficient and time-saving alternative to traditional jointing methods for both solid timber or timber-based sheet material .
by Geoff Wood
Geoff Woods is a furniture designer on domestic and systems office furniture . Whilst at Conran Associates he worked on DIY books for Mitchell Beezley .
Similar in principle to loose tongue and groove joints , biscuit jointing uses ‘ biscuits ’ or flat dowels , ( also referred to as ‘ joining plates ’) in place of a traditional continuous tongue . The biscuits are located in matching semi-circular recesses cut in the meeting faces of the joint , using a dedicated ‘ biscuit jointer ’. Biscuit jointing produces a joint stronger and more accurate than conventional doweled joints , leaving a flush and precise assembled joint line . By locating in short stopped recesses rather than a continuous groove , biscuit jointing eliminates any risk of joint failure due to the weakness of the groove edge , or of the edges curling . To cut the recesses , the jointer is fitted with a 100mm diameter blade to match the edge radius of the biscuits . Fitted with horizontal and vertical fences , inscribed with registration and centre marks , quick , easy and accurate alignment is possible for cutting the corresponding recesses in the joint faces . A graduated depth stop is fitted to determine the depth of the recess in relation to the standard biscuit sizes . Alternatively , where a dedicated biscuit jointer is neither viable or economical , biscuit jointing can be successfully carried out using the router fitted with a bearing guided grooving cutter ( recommended grooving cutter 40mm diameter x 4mm kerf , ( Trend ref . SL / GG ). While the router ’ s depth gauge is used to position the recesses across the joint faces , the depth of cut is determined by the guide bearing diameter , different diameter bearings being substituted to suit each of the standard biscuit sizes . Using the smaller diameter cutter ( as opposed to the 100mm jointer blade ), it is necessary to feed the router along the joint face , leaving a recess or pocket slightly longer than the biscuit length . This allows some lateral adjustment for easy alignment and cramping during assembly . Biscuit jointing operations can also be carried out on inverted or overhead
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INProfile Winter 1997