Friday, 14 August 2015

Humber Speedster Project - Update # 10

I signed off my last blog update saying that this one may include a video of Hubert waking up after some 40+ years asleep. I am very happy to confirm Hubert did wake up and the video below shows the exciting event. The initial start-up took several days to happen after getting the timing right and sorting out some other small electrical issues, then with some coaxing he roared to life, (a wheeze really). The glass ignition coil that I wanted to use wouldn’t play nice on the day, although it tested out OK ?? So I replaced it with a modern type I had on the shelf to keep the start-up on track, (I’ll look in to that other coil later as I’d still like to use it for the look). My concerns about the oil pressure were unfounded as it ran at a respectable 30 psi.


I ran the engine several times to try and bed everything in after the rebuild, albeit some 14 years after! But as you can see from the second video he ran well. The engine now proven I put it back to bed and started on the body skeleton, after being side tracked by relining the brake, clutch and accelerator pedals with sections form an old tyre I had lying about. (I figured I’d do this before I refitted the floor to allow more working space).

After the floor and toe board were refitted I sat on a stool beside Hubert for quite while forming a plan of attack, (I’ve mentioned in previous blog updates that building this body from scratch was a daunting task and took me well out of my comfort zone), I couldn’t put it off any longer so with sketches in hand I took a deep breath and dived right in.

Floor & toe board refitted.
Relined control pedals

The body frame start point    

Scuttle bow template.

The starting point was obvious – the fire wall, so a template was made and the hammering began. My roller was too small to handle the ½” diameter round bar so it was bent into shape the old fashioned way with a hammer and vice jaws open about 150 mm (6”). The process works by striking the material being bent in the middle between the jaws, this causes a slight or heavy kink (depending on how hard you hit it), in the metal creating a bend. It is a tedious job especially if you are bending it to a set curve, sometimes having to flatten out a kink which an over-zealous hammer strike caused. (not that I ever did that….well maybe a couple of times… ;-)  After a few thousand hits you get pretty good at judging the force of the blow you need, and it does form a curve quite efficiently.

Cold bending

The part of the body from the firewall back to the dashboard or under the windscreen is called the ‘scuttle’. From my research it’s called this as it resembles a coal scuttle, or from a part of the ship called a scuttle, anyway I think you know the part I mean.  I formed this by making another bow with the same curve as on the firewall but 50 mm (2”) higher, this gives the rake from the windscreen down towards the bonnet (hood). To get the correct rake I enlisted a few of my work mates and Svenja to look at some drawings and we all agreed that 50 mm was just right. The firewall bow and scuttle bow (for want of a better name), were joined together with straight lengths of ½” bar welded in place, it was finally starting to take shape.                                                                       
Scuttle completed.

Next was what you would call the body 'tub' - the sides and curved pieces that went behind the seat. The curve for the entry openings, (remember Hubert has no doors), was needed so I called on the resident artist, Svenja to give me a curve to work to. I enticed her up to the shed with a promise of a beer and explained what I wanted, she asked me to put a piece of card board across the gap between the seat edge and the scuttle, then with a flick of the wrist drew the ideal curve. (I would have tried to plot it out with reference points, and taken hours!) It was a case of Artist Vs Engineer, and the artist had the goods on the day ;-) I thanked her for her lovely curve, rewarded her with the aforesaid beer then set about to hammer out the curve. The second one was way harder even using the same template getting it as close to the original as possible, but in the end it turned out pretty close.  With the seat frame four curved pieces were needed, two upper and two on the floor. Because these all had to follow the same curve around the back of the seat I decided to make it a bit easier by cutting out a wooden template and using heat to shape them. This certainly saved a lot of time and made reproducing the curves more accurate.

With the bottoms ones finished and in place the seat was reinstalled, (I’d removed it while welding close by on the scuttle to protect it from sparks), Cold bending the top frame to follow the contours of the seat was difficult – sort of a 3D jigsaw puzzle, without a picture to go by! But after considerable perseverance it took shape, assembling the pieces began and it all came together surprising well - another test with the seat in place proved it was all within tolerances, so the support bars were added. 
Svenja's curve.

Perfect fit!

Rear of tub secured to floor.

Current status of body skeleton.
The next job is fitting the sheet metal skin – Yikes!

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