Just putting this up to show how simple it is to make adequate light-duty T-nuts quickly – in fact just using an entire coach bolt of close suitable size. A small reduction in head diameter on two opposite sides fits the T-slot base width – and then often the square under the head fits into the t-slot top width, if same as main thread dia. May not be necessary to machine the domed head if it fits already. This example was modifying bolts to suit a mini 4″ rotary table. Quick and adequate!
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