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Bloodwood Baby Cradle Design Issues

The original design had the caster rails and end posts joined with half-lap joints to minimize weight. This made the ends 36" tall and 36" wide, without casters, which, when double boxed for shipment forced the shipping costs through the roof at $750!! The ends were re-designed into separate pieces bringing the shipping costs down to $95. The ends of the bed are solid (vis-à-vis' the sides) so small children can't get fingers or hands hurt when the bed swings. The span of the caster rails is such that the centroid of mass of the bed doesn't extend beyond the casters when swung out 45 degrees (for stability).

The bed has sealed ball bearings which have a 5/16" internal diameter. I designed custom bearing interfaces for the posts. They are 2" diameter 1/8" thick steel disks with 5/16" machine bolts I welded from the back and turned down on the metal lathe and 3/16" thick brass spacers (also made on the metal lathe) soldered over the 5/16" resulting studs.

This is looking down on the interface between the bed and an end post. The 3/16" spacer sets the gap between the bed and the post for clearance when the bed swings.

An early view in the shop before the hidden jointery was done which holds the bed sides to the ends. Note the cup hole for the sealed ball bearing at the top of the bed end. The bearings are held in with epoxy.

Pocket screws attach the sides and ends to the bottom. A 10-24 machine bolt projects from the end of each side's top rails and fits into a mating keyhole routed into the bed end. Hence no visible fasteners.

First assembly before the stretcher was arched top and bottom and before the gusset blocks were added.

Final assembly of the original design before any finishing. The finish is MinWax Wiping Poly with the last coat rubbed out with 0000 steel wool and waxed with MinWax Paste Wax.

With the original caster rails being only 3/4" thick I added Madagascar Rosewood toenails to cover the tops of the casters. The final caster rails are about 2" thick and didn't require the toenails.