Launch Tower

This is a (mostly) printed Launch Tower for model rockets. The length is 1m, which is _not_ optimal (1.5m would be best) but the tubes I wanted to use come in 1m or 2m lengths so ...

Rather than work through the complications of designing an adjustable tower, different size rockets can be accommodated by printing appropriate sized upper and lower mounts. 15mm and 20mm body diameter .STLs are provided along with the source [Fusion 360 design file](https://github.com/rlhatcher/tower/blob/master/Tower%20Launcher.f3d?raw=true) where the parameters can be easily adjusted for any size.

The original design had printed "pegs" on the bottom mount, which promptly broke on the first attempted use. In hindsight, breaking was inevitable due to the printing orientation so the revised design uses wooden dowels instead. As is often the case, this led to another problem in that 10mm dowelling is _impossible_ to source locally so 8mm dowel with a printed "sleeve" to bring the OD to 10mm and provid