Australian Wood Review – September 2019

http://www.woodreview.com.au 49

TOOLS & EQUIPMENT

the biscuit slot will be. Use the mark to centre on the
pointer of the tool and make the cut. It all comes down to
referencing from matching faces to achieve flush joins.

For better results the biscuit joiner works with the base
of the tool on a flat surface. The weight is down and the
joiner is plunged into the wood. This will position the slot
centred for a 20mm thick board or panel. Placing shims
under the base will raise the slot for thicker pieces. But this
is only for shorter lengths of material. Swing the fence flap
down and rest this on top of the wood, and use that face
for referencing the position of the slot.

The extra adjustable right angle fence slides onto the
main fence and allows height adjustment for materials
thicker than 20mm. On the Makita and Lamello the extra
fence slides on to the main fence and allows good height
adjustment for wood that’s thicker than 20mm. On the
DeWalt the fence is more sophisticated and offers all the
functions as a one-piece unit (photo 1). All machines also
come with an extra plastic clip-on base that allows you to
cut wood 12mm (or 12.5mm on some machines).

Pros and cons

Within a minute or so you have a good clean joint
strong enough for shelves and panel cabinets. Standard
cabinetmaking rules apply still in relation to the length of a
shelf in relation to the expected load and strain on the joint.

The thing is biscuit joinery has strength limits – perfect

for manmade boards in say kitchen cabinetmaking, it will

not be sufficient for a table leg to rail joint. And the same

goes for chairs or any heavy work. Using biscuits for drawer

making is a borderline option – most of the drawers I made

this way stayed together.

However, there are various metal and plastic fittings

available for knock-down and fixed joints giving enormous

strength. Usually these comprise of two parts that mate

and act as clamps as well. Composite biscuits are also

used for manufactured stone joining. However we are only

looking here at standard wood biscuit joining.

Shelf or T-joint

Mark the position of the shelf and mark a line on the lower

face of the side (photo 2). Put the shelf on the pencil mark

and clamp, the lower edge is always the reference face

(photo 3). Cut the slot in the side. With the lower face

of the shelf face down, cut the slot in the end (photo 4).

Photo 5 shows the finished joint.

Mitres

This works best on panels with the mitre point down (photo

6 ). The quality of the mitre will depend how accurately you can

cut the slots. Small deviations that obstruct the mitre on a dry

test fit can be helped by taking a shaving off the biscuit to give

it a bit of play. The biscuits suit frames made from stock at least

5

6 7

4. Cut the slot in the end of the shelf.


5. Showing the finished joint.


6. Cut slots for mitres with the point angled down.


7. Biscuit joinery is ideal for mitre joints.


8. Biscuited corner joint.


9. Showing the slots cut for a corner joint.