Corner fillet

Symo,

First thing you must determine is that the door for the corner unit will open to it’s full capacity without fouling the adjacent drawers and vice versa. More important if the handles you are fitting are deeper than normal.
Fittting of a corner fillet looks better if fitted almost flush (Panels provided are normally carcass guage eg 18/19mm) with the front of the door.
I advise that you remove the corner blanking panel on your corner base.
Line up the corner configuration ensuring you have the correct clearance for the handles and ensuring you leave sufficient room for the corner door to open fully.
Using a straight edge lay this in line with the top rail of the drawer unit and lay across the corner unit. Mark this point with a pencil and measure the distance to the centre of the centre rail of the corner cabinet that carries the door.
With a pencil, mark this distance plus the guage of the fillet piece, (18 or 19mm) from the front rear edge of your corner fillet panel. This mark indicates the back of the attaching right angled piece that will be fixed to it and to the drawer base. On this same piece mark a line again on the rear edge to indicate the middle of the attaching piece. This may be 9 or 9.5mm from the previous line marked and will signify the middle of the attaching panel. Drill three holes in the panel and countersink these. I recommend the holes drilled approximately 120mm from the top, same distance from the bottom and centrally. Countersink these to ensure the screws will grip.
Next, measure the distance from the side panel of the drawer unit to the front edge of the corner unit. If , for instance this distance is 80mm, deduct the guage of the corner fillet and cut the other corner fillet 62mm (for an 18mm cabinet), this size.
This is best achieved with a fine point saw and even better achieved on a saw bench. both edges of this panel are visible and a good finish is paramount.
Place this piece on edge on a flat surface with the sawn edge up.
Place the premarked fillet piece on top of this edge so that it lines up with the rear edge of the attaching piece. The width of this premarked piece need not be cut as it will extend beyond the corner fillet and won’t be visible.Using a small pilot drill drill through the corner fillet piece and into the sawn edge of the attaching piece.Screw the pieces together using 40mm x 6 guage screws and inspect the front profile.

As the rear edge of the fillet attached to the drawer base only meets the front edge of the side gable, you will. in order to fix this, need to attach a piece of 50mm x 25mm par softwood flush with the rear edge of the fillet that will be fixed to the drawer base, (25mm edge glued to the fillet) using wood glue and 3 x 20mm angle brackets on the rear side of the fillet.
When dried you are now ready to fit the corner fillet.

Next screw 2 x 20mm angle brackets using 6 guage x 16mm screws to the corner base unit on the blind side of the centre post and flush with the front edge of the cabinet. This will be used to fix the corner fillet to the corner base unit.
Now fit the fillet through the rear of the corner cabinet and you must ensure the visible front edge of the fillet is vertically plumb fitted centrally to the centre post. There is no alternative but to fix this from the rear and I advise –
1. A companion to ensure it remains central to the post, (failing this clamp a piece of straight edged board to butt up to the centre line of the post) and
2. a cordless drill with magnetic screwdriver bit.
Fix through the angle brackets using 6 guage x 16mm screws
At this stage refit the corner blanking panel to butt up to the rear of the fillet redrilling holes if necessary.

Drill two or three holes, preferrably concealed behind the two hinge plates and, if fitting a drawer line base, remove the drawer and drill a third hole, Countersink these holes and slide the adjoining cabinet up to the corner fillet ensuring it’s front edge is flush to the back edge of the corner fillet. Make sure the fillet leaves an equidistant measurement at the top and bottom of the cabinet and fix through the rear piece of 50mm x 25mm softwood using 6 guage x 35mm screws.
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Not an easy task this by any means but follow the advice and you will have a professional finish.

Tim