Introduction: Oh No Not Another Flippin' Soapbox

About: Trained as a technical illustrator a hundred years ago, Spent 20 years as a professional photographer, boring commercial stuff mainly building interiors and exteriors. Taught cartoon art at adult ed. Last 4 y…

A couple of months ago I applied to enter the Red Bull Soapbox Derby at Alexandra Palace and as I sold the Model 'T' at Bonhams last September and the prototype of the '32 sedan is looking a little 'careworn' I thought it would be the perfect opportunity to design and build a new one.  Eventually I decided on a Indianapolis single seat racer from the mid thirties, a bit 'Milleresque'.  Construction technique follows the previous models.  Plans will be available when I get round to it.

All of the solid timber is Sapele and is obtained from recycled patio door cills from a local window company all for £10.  Softwood could be used instead stained or painted. The floor is 18mm ply, the chassis rails are 4 inch by 3 inch and taper in 2 planes.  The bend in the chassis rail was achieved by 'pie cutting' a wedge and adding a reinforcement piece glued and screwed behind the rail (see photo).

The radiator surround is made up of several blocks glued together and carved to shape, it is squarer than the '32 grille and is therefore a bit easier to carve, much of the shaping can be done with a saw.  The side panels are Mahogany veneered MDF, bending them to form the lower part of the boat tail stressed them to the limit, plywood would have been easier.  Flexi ply would have been easier still.  Normally I would make the bonnet halves from flexi ply and then veneer  them but this time I found some 1.5 mm ply that I thought would do the job but I wasn't happy with the end result so I ended up veneering them anyway.  The windscreen is Ash mitred, screwed and glued with an off cut of Perspex rebated and silicone in place.  Wheels are 20 inch, 40 spoke BMX with 14mm axles.  I made the exhaust from a garden parasol pole, I drilled a hole about an inch deep at the end to make it appear hollow, which has made a few people wonder what it's made from.  The support for the BMX calliper brakes is a 1inch square box section steel which passes through square holes in the chassis rails.  If you have a morticer (like me) remember to make the holes in the chassis rails before you make the chassis (I didn't).  I had the seat back professionally upholstered as it is now impossible to by ready pleated vinyl in this country anymore.

Rick mentioned that the steering is the hardest part and he's right but after 5 different designs I think I may have stumbled on the best method.  The main part as you can see from the latest photo is and old fashioned hand drill bought on ebay for around a fiver I think the photo is self explanatory but will add another couple of photos of the steering arm end.

The front axle was bent out of 19mm mild steel round bar at a local metal fabricator, all pivots and steering links are rod end bearings bought on ebay. 

I will add more photos as I progress with the build.