15 December 2015

BW3W - Balance Bike with lowered suspension

Just completed in time for Christmas is this balance bike for Leon (aged 8 months). A little advanced for a crawler not yet up and running but my enthusiasm rushed ahead unexpectedly.
A Google search revealed a bewildering array of wooden bicycles and tricycles, but settling on this one design was made because it easily modifies from three to two wheels and will hopefully stay useful for longer.

Free running skate board bearings inset to bamboo hubs.

Off-cut pieces of wood chosen for straightness of grain and seasoned quality was sourced at Beach Brothers in Exeter, A strip of garden cane for the axle rods and a length of larger bamboo for the wheel hubs and spokes, Re-cycled wet suite material form the tyres and the Ash handlebars chosen for their crooked angle are cut from the hedge. The wooden tyres are of straight grained oak sawn into 1/16th inch strips, steam bent before gluing into a circular former. Final shaping with the spokeshave removes all sharp edges.
Wheel bearings were found in the skate board shop. 

Failed wheels

Bamboo spokes are approx 5 mm dia.

My steam box (heated by a MSR camping stove) cooks the oak, pliable after just ten minutes. Neoprene gloves enable me to handle while bending the steaming hot wood slivers from the box. This is allowed to cool and dry for 24 hours before gluing up. Three tyres failed the quality test and the final three are far from perfect but would support the weight of an adult. Bamboo spokes may sound a weak choice but testing revealed that a 5mm sharpened spoke may be driven through a plank of white deal wood. A total of forty eight of them were whittled down from the split bamboo with a very sharp 1 inch chisel and a razor plane. The bamboo hubs have a shallow groove cut around the outside close to each end and are wrapped tightly with a ring of whipping twine to prevent splitting. Also to ensure the bearings stayed put.
After this introduction to construction of a wooden conveyance I am tempting myself with the thought of a full size wooden bike,  but on reflection the shed stored classic Claud Butler could not be bettered.

Three and a half years later the bike is still in one piece but required several adjustments to the saddle position. Much abuse from two toddlers has failed to break any part of it. (30thAug.2019) Update.

Front Forks

Some adjustments required for Leon's first scoot include:  Lowered suspension, Widened track  swept handlebars and two coats of varnish.

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