I am going to make a telescope tube about 1200mm long, 300mm diameter. Initially I was going to use a 1500mm Sonotube as a male mould and vacuum infuse the part on to it, however I realise tool removal will be highly problematic. This then leaves me with the option of making a female mould from the sonotube, which is fine seems easy enough and has the advantage of leaving me with a nice surface finish. Will I have to reinforce the mould with plywood to stop it flopping around, say rectangular pieces with a semi circle cutout? If so, when and how do I introduce these? is it between the Coupling Coat and the 450g CSM, or after the 450g CSM?  And what is the best way to lay up the tube with 4 layers of CF for vacuum infusion, as I would imagine it would be a losing battle against gravity if done with the mould horizontally, and nigh on impossible with the mould vertical?