Andy,

I have deleted your other post as duplicate.

I'm not sure that 12 inch 2mm shafts would be a good idea, they are likely to be too 'bendy' between two bearings and inclined to whip. However you can buy them at reasonable cost from ModelBoatBits which will give you a 3/16 inch dia tube.

**LINK**

I am building a 40 inch 1900s liner model which requires 13 inch shafts due to the shape of the stern and to enable access at the inner end. I chose to use 4mm MBB shafts and 8 inch Midi tubes which are a bit over 6mm diameter and then added an extra bearing at the inner end so the shaft has three bearings in all.

The shafts are a bit heavy but the motors I have bought should cope OK

**LINK**

I don't think it is likely that anyone will be in a position to do you a swap, you will just have to sell the unwanted shafts unless you decide to stick with them and accept that the tube diameter is oversize which will only be apparent on the wing shafts. To be honest I doubt if people would notice on such an inpressive kit anyway.

Colin