Hi Richie,
It's not too difficult to create struts if you have the tools and the model has struts that can be used as a size and shape guide.
Of course if you're making a scratch built model you'd need good scale drawings and reference material to work from.
The scale of the model you intend to build will have a bearing on whether it's possible of course - I work in 1:32nd scale so it's not too much of an issue, but smaller scales, especially 1:72nd could prove difficult.
The 'Strutter' tool I use is basically a pair of smooth faced vice jaws that are aligned with metal dowels. As you close the vice the jaws will tip around the tube and form an oval aerofoil type shape.
Basically I cut the required tube to just longer than the length required (using the kit item as a guide) then slide it onto a solid but smaller diameter rod.
That rod is suspended across the two metal dowels in the 'Strutter', which once closed forms the aerofoil section.
That section is the filed to the required length and the ends shaped as necessary.
After that the support rod, which is longer than the aerofoil, is inserted and soft soldered at both ends.
Then it a just a matter of cleaning off any residual solder.
The protruding rods can then be filed down to locate fully into the pre-drilled location holes in the model and if necessary, bent to the correct angle to get the strut to position correctly.
The thing most needed for your scratch build would be good reference drawings so you can use them as a size and shape guide. Upscale the drawings to the size of the model you intend to build and go from there.
There are PDF build logs on my site that detail how I created struts for various models:
Fokker D.VIII (EV), skeletal Fokker D.VII, Sopwith 'Swallow, Macchi M.5 and SPAD XIII,
Mike