Chassis Construction
Post-Paint Re-assembly (Driver Controls - Steering, Brakes, Throttle and Clutch pedals)

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We've installed our Fortin 2.5 power rack and attached the tie rods we fabricated a while back; now we need to connect the steering rack to the power steering control valve and the steering wheel.  That'll require a little problem solving and fabrication; the problem solving involves routing the steering shaft from a steering wheel comfortably located for the driver, past the brake pedal without interfering with it, to the control valve and then to the power rack.  Along the way, we had to fabricate and install bushings for the provided steering column mount and also need to fabricate and install a mount for the steering control valve.  Simple enough but we really need the brake and clutch pedal assemblies installed to insure the steering shaft doesn't interfere with them.  The chassis is set up to use CNC brake and clutch pedals; even though CNC closed up shop, we were able to find the correct pedals in stock at McKenzies - our favorite off-road supplier.  We now have all the steering and pedal components on order; once they arrive, we'll get to work fabricating the remaining steering system elements.


Installing our Fortin 2.5 Power Rack
We still need to replace the hydraulic fittings with 90 degree elbows - we have the correct fittings but we need to remove the rack from the chassis to install them...


Tie Rods installed and roughly adjusted
We also fabricated an identical spare to carry strapped to the chassis


The steering column assembly, now ready to install
The above tubular weldment was supplied with the chassis, we built it into to a "steering column assembly" with the fabrication/installation of bronze bushings, set screws, collars and a universal joint.  This assembly can either be welded or clamped to the chassis in our desired location and orientation.  We left the steering wheel end of the shaft long for now so we can trim it to length for driver comfort (once we determine where that location is).  We'll mount the brake pedal and steering column assembly then locate and mount the control valve.  Once that's in position, we can fabricate the remainder of the steering shaft.


Checking the routing of the steering shaft for Brake Pedal clearance
We spent at least an hour looking at various mounting locations for the steering control valve; we were looking for the best compromise between all the many factors - minimizing universal joint angles, making sure that we could actually install and remove the valve without cutting anything, ensuring that there was room for the hydraulic lines, that there was no interference with the pedals, etc..  We've seen other examples of this car that have the control valve mounted a little higher than the location we settled on - we really didn't like the u-joint angles between the control valve and steering rack that resulted when we mocked that up..... 


Steering wheel and shaft mounted
We borrowed a seat from our 5/1600 car so we could simulate the driver's seating location while deciding where the steering wheel should be located both left-right and forward-aft.  The camera angle distorts the perspective - the wheel was directly in front of the driver with the seat in the correct location.  Trevor says that the location we settled on is perfect.  You can see the universal joint angle here is fairly mild - the steering wheel/control valve shaft operates smoothly without slop.  We'll install the steering column mount more securely than shown here once we are absolutely sure we like how it's positioned.


Universal joints welded on a steering shaft section
After determining the correct length for the steering wheel column/control valve shaft, we welded the universal joints in place.  We wrap the joints in a wet rag while welding so that we don't overheat and ruin them.  We didn't make the control valve/rack shaft this day; the fit of the rack end universal needs some finessing first... We need to remove the rack anyway to install the correct hydraulic fittings so that'll be on our list of things to do next time.


Final steering shaft section fabricated and installed


Steering control valve and shafts installed
This photo is a little deceptive - the brake pedal is well clear of the control valve and does not interfere throughout it's entire range of travel.  The pedals are "hanging" about where they'll "bottom-out" the master cylinders.  The throttle pedal will be installed later and will also have plenty of clearance.  Other examples of this car place the control valve on the top of the tubular member; we chose to locate it on the bottom of the same member to improve the steering shaft universal joint angles after investigating the potential points of interference.  We're very happy with the installation; it's "slop free", smooth and secure.


Foot well area sheet metal trimmed to fit around control valve


Brake and clutch master cylinders installed
With the master cylinders installed, we were able to adjust the push rods to get the pedal positions we wanted and to verify that full travel is available without interference of any sort (it looks tight but there's plenty of room for my big feet without coming anywhere near the steering shaft or valve).  Now that the master cylinders are installed, we can begin installing the brake and clutch lines.  The clutch line is easy - no light switches or residual valves.  The brakes are a bit more complicated; we need a "residual valve" on the rear brakes and we want brake light switches on both the front and rear brake circuits.  The turning brake unit will also need to be mounted and have lines routed to it and from it to both the left and right rear brakes separately.


Clutch pedal "stop" installed
It's important to limit the clutch pedal travel to avoid over-actuating the clutch pressure plate and thereby damaging it.  We machined this assembly to act as an adjustable stop; it replaces the nut securing the clutch master cylinder to the pedal assembly and is easily adjusted as required.


Accelerator Pedal and Throttle Cable
The gas pedal is a commercially available unit but the throttle cable mount isn't.  We milled the mount from an aluminum plate after making a template to insure the shape and location were correct.


Driver's seat installed on "sliders"
We wanted the driver's seat to accommodate drivers of varying size so a "slider mount" was needed.  We chose the "towel bar" style slider rather than the "side lever" type for a number of reasons, including ease of adjustment and security.  The photo is deceptive - there is 1 1/2" clearance between the seat and the center "tunnel".


Passenger side slider base installed
We installed an identical slider base for the co-driver - it's not absolutely necessary but it might make it more comfortable for the co-driver.  


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