2026-01-24

Last modified: 2026-01-24 23:18:23

• Car chassis rails
• Car

Car chassis rails

I made a 3d-printed jig to clamp them:

It wasn't a massive success as it was too flexible, as you can see I had to remove my first attempt at a tack and try again. But it was a good reference to verify the angle after-the-fact.

To tack up the second rail I clamped it to the first:

I wasn't sure whether to grind back the welds or not, in the end I did:

I started trying to drill for the axle with the 30mm holesaw but the run-out on this thing is absurd: https://img.incoherency.co.uk/6458o

It is wandering by about 3x the blade thickness. And the cordless drill battery was flat so it is on charge now.

2 rails:

And now with bolt holes drilled, and spacers tacked inside the rails:

It is quite deep inside the hole so rather tricky to weld, but the weld isn't exactly important, just needs to keep the spacer from going missing.

I've done the spacers on one rail, then ran out of welding wire so had to stop for now.

Car

So the plan now is:

• make 2x spacers for the rear axle bearings (good fit around M12 bolt, good fit in mounting hole, just 1 per bearing)
• when the taper lock hubs arrive, measure the bearing/hub/wheel stack and ensure it will fit on the axle
• cut and weld chassis cross-members (just 1 front and 1 back for now?)
• also have a look at the bolt-on hub and see if it would be convenient to use with the rear brake disc, else design something for a weld-on hub, and order the required hub
• make leaf spring hangers (fixed for front of spring, pivoting for back)
• when the spot-facing tool and Rapid Metals orders arrive, spot-face the front wheels and make the spacers for mounting the disc carrier
• also drill and spot-face the rear wheels to suit the taper lock hubs
• then design the front axle and order the parts/materials