Those who have built their own chassis , how accurate did it come out compared to Mc Sorely or book? Is tolerence ±3mm OK?

I am really not sure how to resolve some of the angled tube to flat face issues quite a few of the junctions like this are not detailed as to how the extra bit of the angled tube is supposed to lie.

Caber 4 days into build!

I'd say +/- 3mm is fine and probably better than a lot of production cars.

Think mines about +/- 5mm overall.

Pat...

I mentioned accuracy when I visited CBS - they had just finished a Foreman Can Am and said I'd was about 3 - 4 mm on the diagonal (corner to corner) and they reckoned that was about as good as you could get!

Getting the mounting points in the right place for suspension/steering is the critical bit - I your chassis ends up a foot longer on one side, it won't matter so long as running gear geometry can be set true, if you see what I mean

So you'll be fine.

ATB

Simon

[Edited on 29/12/05 by Simon]

Mines chassis is about +/- 5mm on the diag.

The inaccuracy of the chassis can be no more than can be corrected by the suspension adjustments.

To be fair, most production cars are about 4mm, but I was very surprised by porsche, they are just about spot on, you get what you pay for.

id say thats fine and the important thign is the placement of the suspension pickup points.

Mine was 4mm out on the triangulation but this will be solved by adjusting the panhard rod for the dedion.
The front was pretty much spot on.

Heres the thread i started about mine.
the pic isnt their because im in the process of changing the gallery software
http://locostbuilders.co.uk/viewthread.php?tid=36055

[Edited on 30/12/05 by Gav]

Took mines of the jig yesterday after fully weldin its only 2mm off on the diaganols and it has a torsional twist of about 4mm along its lenght ( as best as i can measure anyway. Ive still got the tunnel area to do and a bit of triangulation after some major parts (engine) have been decided on and sourced.
I'm quite happy with that (should I be)?

+/- 4mm seems the norm, a lot depends on the jig and your welding schedule when you complete the tacked up chassis. Will discuss options if I get through to yer den early doors next week. Suppose this means I got to stay kinda half sober at Hogmany then??
Shug.

Shug

No need to stay even sober ish! Hangover should be gone by Tuesday and I am still off work then!

Caber

ah but I have been on the pop for three days now just warming up for Hogmany!

4mm on chassis diagoal is pretty good.

What I would recommend is welding on the critical points ie suspension pickups last. This means you can compensate for any chassis inaccuracy.

I tape cardboard to a flat surface (garage floor) then draw out the suspension pickup points. The chassis is then put onto the cardboard and it is quite easy to get the position of the lower pickups within 1mm. To do the tops you have to get clever with plumb lines, engineers squares and spirit levels.

John