It's been over two years since I finished the Artist's Proof (AP) for a tiny edition (less than 5) of Co-Hog Porsche 935 sculptures. Other projects are still in the process of being completed as you can see from other blog posts. I also have quite a long list of blog posts still to do and I recently re-discovered one that relates directly to the 935 edition.
Although the basket weave wheels shown here look great, I will offer the option of turbofans as well. This post will concentrate on the creation of the prototype which was finished shortly after the AP 935 was done.
The completed AP 935 is shown here on its simple prototype base.
A comparison of the turbofan wheel and the standard wheel shows how turbofans would give quite a different appearance as they become much larger graphic elements rather than providing a big dose of details to focus on.
Development started using CAD before turning the aluminum and brass parts. The turbofan was machined from aluminum and the wheel center, nut base/axle and wheel nut were done is brass.
Section views give a more detailed view of the construction.
As with the 1:1 versions, each turbofan is an addition to a standard wheel. Here the turbofan has had the inside profile turned.
Turning the inside and outside tapers on my small lathe requires the use of a specific compound slide where the cutting is done on the back side of the part with the tool turned upside down.
This is shown just before before the turbofan is parted from the base.
Here the outside profile has also been completed - ready for a quick polish, etching primer and paint.
The axle stub/nut base and wheel nut were turned from brass. They can be a bit finicky, but my lathe upgrades have made a big improvement in holding dimensions and keeping the cuts clean.
The last brass part is the wheel center. Two coats of metal etching primer and a base coat of white were applied to the turbofan before final color. Each of the brass pieces was also metal etch primed before painting.
Anticipation was immense as I neared final assembly. The turbofan prototype (circled) rests with the major subassemblies before final assembly.
To see more about the Co-Hog AP Porsche 935 development process check out these previous posts :