The bowl is the key element of the routing table. It fits the rabbet of the spindle moulder recess and allows accurate repositioning. On the other hand it prevents ships from spreading into the table and channels the dust to the recess extraction. Lastly the top bowl accommodates a metal table ring of the spindle moulder and the top table sits on the bowl through a screwed medium density fibreboard ring.

At low speed meaning about 25 meters per second, I sawed a strip in the 40mm thick polycarbonate shelf and chamfered 45° the four angles so that keeping an horizontal surface when assembling the octagon. The tilting blade and fence angles may be computed with that compound angle calculator. I stuck the eight parts and trued the underneath with the sanding disk then thickness sanded the above with the same accessory.

Calibrating the external shape on the spindle moulder would have been the fastest but there were much material to remove and I was afraid vibrations tend to break the fresh glued joins. Besides diameter dimension didn't really matter and using the pattern sawing technique with the angle fixture I spend much time to get a smooth cylinder.

Opposite to above I wished the fitting between the rabbet recess of the iron table and the bowl as close as possible. It would arguably improve the recess dust extraction as well as the accurate repositioning. The rabbet was machined with an insert rabbeting cutter and a suitable guide ring. The same method was applied to chamfer the bottom with an adjustable bevelling cutter.

With the same fear than above about joinery I preferred spending much time with a grooving cutter rather than a rabbeting one and machined the above rabbet by lowering the cutter step by step. On the other hand that method allowed the same ring guide to be kept whereas the rabbeting cutter would have required the use of a smaller ring each pass.

The safest way of machining the inside rabbet accommodating the metal table ring was to make a template. The good news was that template would also turn into the needed spacer linking the bowl to the top table. The circle jig helped for the routing of the shape matching the metal ring diameter then a straight router bit in conjunction with a ball bearing fitting the shank diameter enabled the inside rabbet to be machined along the same template.

That versatile template also helped the bowl to be clamped on table and an adjustable bevelling cutter machined the inside cylinder by slowly rotating the micro adjustment lifting mechanism of the spindle moulder. The chip collector was merely the planer-jointer dusthood.

I made some other passes that were not required but aimed to improve the dust collection and reduce the bowl weight and eventually drilled eight countersunk holes allowing the bowl to be screwed against the top table.