desk and work table

Instructions

This folding table has a desktop of 120cm x 80cm that becomes a table top of 120cm c 160cm, The geometry of this is such that, when open, the overhang is 20cm on each side, with at least 3/4 of the width of each leaf supported by the legs. This makes for a pleasing symmetry. The two factors to achieve this are proportions of 2:3 which become 3:4, giving an equal increase in size in each direction, and the precise location of the pivot (a Lazy Susan bearing plate), which, for this project, is centred 20 cm from the centre of the base in the X and Y axes. Trust me on the math. The hemlock for the base was supplied by Pear Stairs and parts for stair cases. hardwood being really hard to get in the UK (It's considered specialist!!!) I ripped two newel posts down from 90mm to 75mm. The joinery was all cut with Shaper Origin with an 8mm x42mm upcut bit. The only issue encountered was having to find a way to mount Workstation high enough to get 1110mm of wood set up to mill end grain. I ended up with my router table top propped up on piles of systainers to get this clearance. The mortices and tenons were cut with the same template but with mortices offset by 3 mm to allow for the roundover on the legs. A 3mm roundover was used to soften all the edges. The tops of the legs were also milled out to accommodate the plywood base board. There is no SVG for this or the rabbets on the stretchers as they were cut using on-tool rectangles but the corners are radiused at 20mm and both the corners and rabbets are to a depth of 18mm (the plywood thickness I used). The legs also have low profile screw in feet for levelling but these are an optional extra. Having assembled the frame, I relied on actual measurements for the plywood base (not trusting pre-calculated dimensions) It was cut with the same 8mm bit from a sheet of 18mm hardwood ply and the recess for the Lazy Susan bearing plate was cut at the same time. Again, this was done on-tool, being just two consentric circles. I did also use shaper to position fixing holes for the bearing plate (I used M4x10mm threaded inserts to bolt it down, since there is no load on these screws in normal use). Two additional 20mm holes through this base board allow access to screw the table top to the bearing plate later. 150mm in from one corner (to left in the picture of the table base) is a hole for the latch bolt. I used a spring plunger and made 0.5mm oversized receiving holes in one of the table leaves. The positions, relative to the pivot point (which, from the bottom left corner in my photo is X=400,Y=200) are X+450mm, Y+250mm and X-250mm, Y+450 The hinge recesses were cut with Plate and a 3mm cutter (with corners fettled out with a sharp chisel afterwards). I was worried that cutting away so much of the stretchers would result in flexing in the middle. This was unfounded. The permanently attached base of plywood adds more than enough rigidity. The finish is two coats of india ink on the base and two coats of Fiddes hard wax oil on everything.