Where is the best place to buy the rhs steel and how much to i need?
Look in the Yellow Pages for local steel suppliers.
From: http://gtslocost.locostsites.co.uk/locostfaq.htm
"Around 31metres of 25x25mm 1.6mm section, aound 9 metres of 19x19mm 1.6mm section and around 8metres of 19mm round."
You also need sheet which the book lists sizes of.
The steel is supplied in 6m lengths. I bought a bit extra to allow for mistakes and practise. I seem to be using it up at about the right rate 
As for a supplier, search for steel stockholder in the Yellow Pages. It's worth phoning around. I saved about
£40 against the most expensive supplier by going with the cheapest.
That’s an incredible amount of steel when you think about it...
quote:
Originally posted by macnab
That’s an incredible amount of steel when you think about it...
It looks next to nothing, but sounds a lot, and soon turns into something very rewarding!
quote:
Originally posted by David Jenkins
I wish I'd taken a picture of mine before I started cutting it up, as a reference point.
There's no 19mm RHS there, my local stockholder didn't have it in stock so that's the 25mm RHS, 19mm round, blockboard &
sheet there. So what size did everyone order of 16swg steel sheet?
I bought an 8ft x 4ft sheet, forgetting that you can use 18swg for the floor of a 750mc car.
Oops.
Yeh, I notied that you could use 18swg in the 750mc regs, bit late now, the 16swg is ordered. Do you think there will be much weight penalty (to make it worth changing)?
The density of mild steel is 7.85g/cm^3. So, a whole sheet (250x125x0.16cm) of 16swg is 39.25kg. A sheet (250x125x0.12cm) of 18swg would be
29.44kg.
The difference is enough to convince me to change, especially if I'll be gunning it out for last place with you 
quote:
Originally posted by ironside
The difference is enough to convince me to change, especially if I'll be gunning it out for last place with you
Yes, I think 9kg is enough to convince me also, I will see if I can get the order changed with K Steels or I'll just order
the 18swg as an additional item and make a welding table with the 16swg
You'll still use some 16swg in other places. The floor is the only part 18swg is allowed afaik.
The ends of the footwells spring to mind, can't think where else just now.
It sounds a lot, till you do the maths.
130 feet x 4" (4 side of box) =
130' x 0.33' = 42.9 sq ft
sqrt of 42.9 is 6.6 feet sq.
About enough to do the roof of a large estate car.
So in reality, not much.
Very eco friendly if you ask me
ATB
Simon
The steel arrived today. My god that piece of 3mm steel sheet is heavy! Not quite sure how I am going to cut that up yet, angle grinder hardly made a dent (rubbish cutting disc?) and tin snips wont be up to the job. Suggestions?
I did mine in the chop saw.
It was already in 4" x 12" cuts so it was narrow enough to fit. Took awhile but it worked.
Damn, I think I may have under-ordered on the 18swg sheet. Only got 2m x 1m. Dont have the book/plan with me at the moment. Is this going to be enough for the floor?
Should be enough if you're not covering the underside of trans tunnel.
Cutting the 3mm, I'd use a 1mm grinder blade.
ATB
Simon