There is a small article in Living Woods, Sept/Oct 2010, on building a hazel rod playpen (which can easily be flattened for storage). Rob Exton used a Veritas Tenon Cutter (which you can look at at axminster.co.uk) on the ends of each of the roundwood hazel rods, which fit into some planed wood. The rods were less than 100mm apart so that toddlers wouldn't jam their heads through, and with sheets draped over the top, the playpen becomes a sunshaded place to nap.
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