Front upper wishbones

The front upper wishbones should be a bit easier than the lower ones, smaller thinner tubes and no plates. However, there were two measurements I needed to sort out first.

Number one, the angle of the insert. I now have two inserts that have been welded inside a 25mm tube. The tube itself is 50mm long, so comparing that to the plans means I'm 5mm narrower and 10mm shorter. So all the measurements on the wishbones go out the window! To get the insert angle still at 8 degrees, I had to work out how many spacers I needed. A quick bit of trigonometry left me with 7mm of spacers required at the end, to give me an 8 degree angle.

Number two, caster angle. I'm not going rosejoints at the moment, mainly because I'm not building 'that' sort of car. I will keep an eye on rosejoints as an upgrade, but not for now. Which means I have to get the caster angle right first time, and the asymmetrical wishbones are the perfect opportunity. I am aware that 'the book' has messed up the calculations, and only gives 3.5 degrees rather than 7 (although I think this is the '£250' book rather than the 'on a budget' book). But I'm not going by 'the book', I'm mixing up various sources. So I had to work out what was ideal.

From various forums, I have 10 degrees as being a good start, so as close to that as possible. Given the measurements in the book and on my own wishbones, I worked out that with the upper wishbones as they are in the book, I would get 7 degrees camber. With the Saturn measurements, I would get 6. Yes I know it's not quite 10, but the higher the better so I'm going with the book measurements. This means an offset of 120mm for the centre of the insert.

And that's where I ended the day. The jig was sanded down ready for a new set of markings, the thin tube is ready to be cut, and my forearms are ready for a shedload of hacksawing.