Starting To Take Shape

Quite a bit of progress from last update, both visibly and "non-visibly". When I say "non-visibly" I mean that some key decisions have been made or key parts have been sourced which may not be visible but are equally important.

The main non-visible progress made was in the resolution of the rear suspension dilemma. This has been my main source of delays in the past few weeks and it is a real step forward to put that behind me. The resolution came in the form of an MK Engineering de-dion suspension kit which I bought second-hand but unused from one of the other LocostBuilders.co.uk forum members (Thanks Chaz!) He bought it a while back but it is now surplus to requirements. He also supplied me with Sierra rear hubs, disks, hub carriers, driveshafts and a differential with mounting brackets. This comprises most of the rear suspension system with only trailing links, panhard rod and brake calipers left to be sourced.

The only problem with the above setup is that it is designed for a standard width chassis and I am using a +4" chassis. This has meant that I have had to effectively re-engineer the rear chassis to make it standard width in some ways and +4" in other ways to allow the suspension to mount correctly. In practice this meant moving tubes K3 and K4 outboard 1" each so they are now in line with A1 and A2 and also moving tubes RU1 and RU2 inboard 2 inches on each side to allow the de-dion assembly to articulate correctly without fouling. This also means that I have to mount my rear trailing links on the inside face of tubes M1 and M2 instead of the outer face. I intend to use spherical bearings to help minimise the intrusion into the cockpit and create a box section around the arms which should be okay. Since my chassis is 4" wider than standard the 1.5" intrusion on each side should not be a problem.

Recent Progress

As you can see, the rear suspension tubes are now in place behind the seating area. Note also that I've created the first section of transmission tunnel. I can't complete this until the diff position is finalised though.

Here is the diff and one of the shafts in place (roughly).

This image shows the changes made to accommodate the de-dion axle and ears. The changes are designed to allow the ears freedom to come down below the plane of RU1 and RU2 which is necessary on full rebound. You can see that I have highlighted the tubes involved and shown how they have moved. Note that there is now a clear line between the mounting lugs on the "ears" and M1 for the trailing links.

 

Well that's about it for now. I'm busy creating a CAD drawing of my chassis in Solidworks so that I can see how things will go together before I actually weld them from now on...

Chassis Welding Continues

Just in case you are all thinking that I've got fed up already, I have been working on the chassis the last two evenings after work. My Boss has loaned me his 120 Amp welder (Thanks Derek!) and it is making much better progress with the 2mm thick tubing. I discovered just how bad my welds were when I turned the chassis over to tack weld the back side. The whole thing kinda folded in half and broke some of the welds. Over the last two nights I've been sorting this out and all I need to do now is grind down the welds I made tonight and start building the next layer. In case some of you are wondering just what this is supposed to look like, here is a rough idea from "The Book"

Well that's all for now, I hope to make more progress at the weekend when I can make more noise with the grinder without upsetting my neighbors...