1978 Reliant kitten rebodied in hand formed aluminium

Pleased you had a good day. Now if that TIG behaves itself…

A change of scene today after the euphoria of yesterday; a bit of hammer forming. I need to add a curve to the door frame mirroring the shape of the roof so to start with I played around with a length of welding wire to give the desired curve. This was tacked in place and the curve transferred onto a piece of thin ply.





Two pieces of 12mm ply were cut out using as a pattern the curve on the thin piece. These two pieces are the basis of the hammerform which I'm using to tap over the flange. 







A left and right hand piece will be made for each side and welded to form a U section with square corners. The final internal width will equal the diameter of the round tube so that they can be slid upwards and welded in place.

This is a classic example of what happens when there has been no planning and no drawings. As I have mentioned before I'm useless at drawing so the shape has evolved over time. It wasn't until horrido came up with the artist's impression that I realised the door frame needed to follow the curve of the roof. The 33.7mm diameter pipe frame is unfortunately cast in stone and cannot be bent. At one time I was considering sculpting it which is probably where the confusion has come from but I felt that in doing this a lot of strength would be lost. So that's why I came up with this solution which loses a bit of headroom when getting into the car but retains the integrity of the cage.

So following on from yesterday I cut a length of 1mm flat 33.7(ish)mm wide and tacked it to one of the hammer forms


I then offered it up and realised that I hadn't taken into account the fact that the screen frame splays out from the roof to the scuttle. Fortunately I hadn't welded the other side at this point so it was easy enough to cut out a cheese wedge and put in the bend. The second piece was then added and tacked in place.







It's difficult to gauge the full impact of putting in this curve without having the bodywork in place but I'm hoping it will have the desired effect.

At the same time I do have doubts because of the vertical drop from the roof to the door aperture where a subtle curve is needed so I am bracing myself in case it has to be rethought.

I really appreciate your thoughts, thank you. I think it's marvellous that folk are sufficiently interested in this project to get involved themselves and offer their thoughts and suggestions. 

I've just covered the area with paper and I can see at a glance what's wrong. Take a look at these pics.











The last one says it all. Rather than being vertical the piece should angle out and follow the line of the B post. ie angled in towards the roof or out towards the floor. The only bit that's correct is the section on the windscreen frame. It should be possible to form the aluminium so that it has a curve rather than following the a  crease of the steel and fitting flat against it.

So, we're looking at removing it to make way for the MK2. Fortunately I haven't made the second side so it could be worse.

I can't see a way to transition the curve of the roof skin around that straight line above the door.

Touring seem to have formed the window frames without any additional internal roof support.
Wow, there's really nothing to these is there!

Now that really is Superleggera. I'm sure because Touring designed it then there is no problem with rigidity but if I'd done it I would be really concerned partly  about not having put sufficient  strength in the structure as a firm underpinning of the aluminium skin but mainly from a safety aspect and how much protection it would offer in the event of a crash. 

If you are right about there not being a curve from the roof to the window frame this could cause some serious thinking about how to progress. The shape you have drawn is really beautiful and I'm striving to copy it as well as I can.  I said earlier, the two main tubes are set in stone because they are fundamental to the structure of the cage and cannot easily be altered but you have opened my mind to the possibility of cutting them out altogether. I'd be prepared to sacrifice a little rigidity and strength if it meant that it would contribute to the stunning creation that you have realised and that I desperately want to produce.

Nick perhaps we can talk structural engineering when you come over 

When I first read your post I thought NO,  but having given it more thought, you are absolutely right. Those two rails have to be bent to follow the curve of the roof and anything else is just a fudge and would ruin the shape. And  it's something I would always regret not doing properly when it was too late to change it. A good call.

Thank you blackpopracing.

That is what i was getting at with the red line .

could you do a short video of a fly past of this area, it's hard to understand the form fully from these pics.