Hey Guys,
I thought you might like to see how my chassis design evolved for this proxy...
Initially I was wanting to build as light as possible and create as much downforce from the aero shape of the body, in keeping with the spirit of this proxy. So I took the Ugo chassis as my start point. However, I wanted to give the front axle a little more support and so added two more rails to form a strong triangular shaped chassis...
Next, I began to think of ways I could transfer the downforce created (hopefully) by the front spoiler directly to the front of the chassis in an attempt to keep the guide in the slot, and so I decided to do away with the bent wire axle of the Ugo and instead use an axle tube on which the front of the body could bear down. I also thought that to save weight, the outer rails could double as axle tube supports...
Next I began to consider how the body attached to the chassis. Here the pin tubes are soldered on top of a hinge tube that wraps around the main rails...
Having discussed my chassis design in post on Slotblog, I got a PM from my "Chassis Mentor" suggesting that the Ugo chassis would be light up front and I shouldn't rely on aero to keep the guide in the slot and instead should concentrate the weight just behind the guide and so taking his advice I decided to span the width of the chassis with a strip of brass centred on the front axle...
As I enjoy cutting brass, and curvy elegant shapes I decided to make more of the front brass work. Further refinements of the design also showed that I could use the centre rails to add support to the axle tube (previously I had imagined a length of square brass tubing running under the axle tube) and I was pleased with the economy of the design. Note, the pans design had changed at this point and was of the shaker/flexi type. I didn't realise that they were outlawed until later.
Finally I moved from pencil sketches to some 2D design software I have which allows me to correctly dimension everything and print off templates for cutting brass with my trusty piercing saw. At this stage I finallised the pans design with hinge tubes up front and alongside of the rear bracket. The pin tubes double as hinge wires and some piano wire reinforcing to the front hinge tubes doubles as an up-stop. Here is how the chassis looks as of today...
I haven't designed it to be 'Choti', 'Vintage', 'Retro', 'D3' or any other 'type', just to work well with my body and to stay on the track in the fast curves. As far as being period correct, well it has Kai wheels, Rehco rear bracket, Parma Crown (stained black) and 16D motor and if I had been a young lad walking out of that model shop in 1970 with a bag of goodies and worked through this same design process I believe I would have come up with the same answer.
BTW, I'm really pleased with the chassis, I've no idea how it'll run, It might turn out to be a real dog, but I love the economy of the design, and the pans make a very satisfying clunk when the hit the travel limit.
Hope you've enjoyed the read.
ATB
Al.