Anatomy of Slippery Anne

[DavidL]

Is the driving position with feet higher than the seat base?

Am also trying to work out what takes the weight of the passengers. There's a light looking flat frame just cantilevered?

[Mark Atkinson]

Is the driving position with feet higher than the seat base?  

Am also trying to work out what takes the weight of the passengers.  There's a light looking flat frame just cantilevered?

Hello David,

Yes, the drivers heels are 7" above the seat base, rather like a modern formula one car. Unfortunately, the seat back is not the least bit reclined, I have made the body to be exactly the same as original, but after many contortions trying to make it work and much thought I have concluded that I need to cut it back by 4" so that I can actually get in the car and drive it. I will then have a 'slot in' piece of the cockpit coaming to fit into place so she looks correct and to suit smaller drivers.

Back in the day Slippery Anne had a problem with structural failure of the body, she quite simply broke her back, Waite had to drop out of races because of the issue, they supported the drivers seat from extensions to the spring pocket chassis sections which fitted over the springs, just as Gordon England did with Mrs JoJo, which also has a central mount coming back from the cross members, but, I cannot find any evidence of such a central mounting on Slippery Anne! So the seats where slung like a hammock between the springs, there may have been something in the middle, but I don't know.
Beatrice knew that John Pares had strengthened the car with some sort of frame below the seats and floor, but had no idea what. Certainly, whatever he did it worked as there are no records I have seen about the car having any further structural issues following his rebuild in late 1926/27
For my part, I have fitted the side mounts formed from the spring pockets, but also made a steel frame with stressed T6 alloy skin floor which is triangulated up into the top of the rear cross member. The seats, also made from T6 aluminium, straddle the torque tube and form a torsion box around it, they also tie into the triangulation, This structure also takes the loads from the rear body work, so hopefully she wont break her back. This seat/floor assembly also provides the location and mountings for the suspension fairings. The whole structure has come out very strong and most importantly has not taken away any space from the seats.

So, rather than cantilevering out from the cross member, the floor forms a part of the outer mould line of the body shell and is hung several inches beneath the main  chassis rails and cross members. The chassis is effectively surrounded by the body shell. This is as close as I can get the car to how I understand it to have been back in the  1920's.

Regards, Mark

[DavidL]

An interesting challenge threading between known facts and heresay and second guesses and practicality....am sure but one of many...

[Mark Atkinson]

Having already made tooling for the louvres when I fabricated the cars nose, I made some rapid progress with the bonnet on Saturday morning, managing to progress from raw sheet of aluminium to an almost finished side bonnet in under 2 hours, before family activities took me away from the workshop.

   
   

When I returned to the garage I had no clear idea how to make the hinge, clarity coming in the form of some excellent guidance from Mr Williams, who inspired my next steps. Thank you Ian.

I decided I needed to practice on a smaller bit of the car and set out to make the fuel tank access hatch, this is located atop the cars fabric tail section and is only a few inches across. First thing to make was a bit of tooling in the form of some old and broken mole grips modified by the addition of some 1/4" steel carefully ground and welded to their jaws.

   

I also ground a chamfer onto the long edge of some 4"" steel bar, which when clamped onto the sheet alloy I was using to make the hatch, allowed me to chase out the initial shape of the hinges from the flat alloy I used for my hatch. None  of which I photographed!
I found that as the curve developed, that by gradually moving the chamfered bar back and re clamping, I could increase the curvature until the tail had come through 180 degrees. I then replaced the chamfered bar with round bar of the correct diameter and chased the final shape with a piece of tapered hard wood, following up with my modified mole grips to close up and finish the hinge.

   
   

Equipped with this experience I will now have a go at the rather larger bonnet hinge.

Regards, Mark.

[Ian Williams]

Glad it worked out well Mark, it will be interesting to see how you fair with the main hinge next, excellent with your talents I am quite sure!

[Greig Smith]

Mark you are doing a fabulous job, I love the big blow up of Slippery on the man cave wall - part wall art / part inspiration and guidance.

Having just finished the aluminum body of my single seater....if a race car can ever actually be "finished".... I found that if I heated, (annealed), all the edges and places where I made lumps or tight corners and raised bits with a small hand held propane torch it made a remarkable different in the workability of the aluminum.

Aye
Greig

Sunny South Africa