DavidBigcheeseplant

I have never had an issue with Fusion 360 as I am only using it for my own use, the paid for version has things I don't really need, although export of DXF files would be useful.

I use AutoCAD everyday for my day job, Fusion 360 even though it is an Autodeck product, it works or looks. Although there are similar commands such as mirror array etc.

I am not familiar with FreeCAD I use Fusion which in the hobbyist version that I use is free. For the locomotives I have drawn, I start with the wheels, I have devised a parametric program in Fusion that allows me to put in wheel diameter, number of spokes, shape of spokes and all sorts of other variables, I can put in exactly the wheel I want and Fusion creates it. I can then export the wheel as a STL file and print it. inserting the wheel into a turned Alan Gibson steel tyre.

I notice that you are designing the Planet full size then scaling it down to 4mm scale, I think if you do this then you will run in to a number of problems , probably the biggest being you are modelling it in OO gauge which is 16.5mm gauge if you draw it at prototypical size then scaling down exactly will gauge it at the correct 18.83mm gauge, so splashers and wheels will need moving in and clearances will be changed as you will be using larger than scale flanges. David

This is a link to the High Level kits gearboxes https://www.highlevelkits.co.uk/gearboxes He sells a gearbox to fit in a tender and drops the drive to below the footplate to link with small gearboxes he sells for the driving axle. I would start with these and then design your planet round these. When I designed my broad gauge locos I drew them in 4mm scale not full size, as I has to thicken various parts slightly to print.

I find this thread interesting both on early locomotives and CAD design. Instead of putting the motor in the loco it could be placed in the tender and drive the loco via a cardan shaft to the loco, allowing more weight to be placed in the loco. Have you thoght of using High Level gearboxes.

The locomotives there is not much info on only a few drawings and a couple of photos, so have had to look at other classes of the same period to answer some things I was lacking on but hopefully the designs are as accurate as my research allows, They are designed in Fusion 360 in 4mm scale and have inside cranks coupling rods and pistons which all move correctly when the wheels rotate. The buildings at Wycombe were again constructed from site visits old photos and maps, Thame station was to exactly the same design and the original contract drawings exist, which helped my design. The brickwork on the model matches the prototype, and so have tried to be as exact as possible. The same goes for the locomotives counting rivets and bolts if needed. Anyway a couple more renders.

At the moment the 3D prints are static but I plan to design proper kits but need to design the etched parts. I plan to make a model of High Wycombe in the 1854-64 period. It is a case of design and scratch build everything. Even the trackwork I have created my own system where code 75 rail is slid in to a 3D printed base to produce the GWR bulk road of trackwork. This is one of the laser cut walls of the station building showing the brick and flint detail. The actual Brunel station still stands.

Yes they are to 28.08mm gauge. I have drawn up coaches and the entire High Wycombe broad gauge station at High Wycombe 1854-1864 too, I have exported files to laser cutter to produce the buildings too.

I have drawn up in Fusion 360 two GWR broad gauge locomotives the Sun and Bogie class, I have exported the files to my 3D printer and produced actual models. David