For accuracy, what size thread should I use to connect my telegraph poles in OO/HO and N gauges?

To ensure accuracy and realism in connecting telegraph poles in OO/HO and N gauges of model railways, it is recommended to use fine-sized threads. The choice of thread size depends on the desired scale and the level of detail and realism an individual modeller wishes to achieve.

For OO/HO gauge, which has a comparable scale of 1:76, it is advisable to use thread with a fine thickness. Commonly, threads in the range of 0.2mm to 0.4mm in diameter can be suitable for this scale. This size will provide the necessary delicacy and proportionality when representing telegraph wires and connections.

For N gauge, with a comparable scale of 1:148 or 1:160, even finer threads are required to maintain accuracy. Threads of around 0.1mm to 0.2mm in diameter are commonly used for this scale. These thinner threads will better replicate the relative size of actual telegraph wires in relation to the reduced size of the models.

It is worth noting that these thread sizes are suggestions based on typical modelling practices and the desired level of realism.  It may be necessary for modellers to experiment and adjust the thread thickness to achieve the most visually accurate representation based on the specific requirements and preferences of the modeller.