Ok, i know this has been asked loads of times before but just to be clear. I've just phoned a steel fabricators near to me and enquired about the steel for my chassis.
I asked for:
25 x 25 x 42m
20 x 20 x 12m
40 x 40 x 6m
when i asked him the wall thickness, he said he was looking at about 2.5mm. I know in the book it says you should use 3mm. Will this make a difference?

personally I'd still try and get 3mm but that's just me. Did you get told which grade it was?

just noticed the engine, get solid bar

[Edited on 25/4/07 by Mr Whippy]

2.5mm??? 3mm

I think you will find almost everyone is using much less than 2.5mm wall thickness!

I think you have got your material thicknesses wrong. 2.5 and 3mm thick material is RHS (rolled hollow section)
The size range of this type of material goes up to about 400mm square in 15mm thickness, for building structures.
What you want is 1.5mm wall ERW (electric resistance welded tube). This is essentially sheet metal tube.
The 20mm material on your list in ERW may be 19mm.
For reference a lightweight race chassis uses 1.2mm thick ERW.
HTH
Mal

Ok, is there anywhere online to get it? I've looked at Shop4Steel.com but they are REALLY expencive.

a quick search for your area turned up this


No results in Eastbourne so your search has widened to East Sussex
DENMAY STEEL & HIRE CO
137, Wellington Rd, Portslade, Brighton, East Sussex BN41 1DN
Tel: 01273 430399
Matches: steel
• 50 Tons Steel Stock • Beams, Angles, Flats, Tubes • Reinforcement Bending • Fabrications, Balustrading • Fire Escapes • Free Local Delivery
Steel Stockholders

Fowle & Co.Ltd
Tremlon House, Menzies Rd, St. Leonards-On-Sea, East Sussex TN38 9BQ
Tel: 01424 444666 Steel Stockholders

J.S Steel Services Ltd
25, Sedlescombe Rd North, St. Leonards-On-Sea, East Sussex TN37 7DA
Tel: 01424 465000 Steel Stockholders

quote:

---

Originally posted by Mal
I think you have got your material thicknesses wrong. 2.5 and 3mm thick material is RHS (rolled hollow section)
The size range of this type of material goes up to about 400mm square in 15mm thickness, for building structures.
What you want is 1.5mm wall ERW (electric resistance welded tube). This is essentially sheet metal tube.
The 20mm material on your list in ERW may be 19mm.
For reference a lightweight race chassis uses 1.2mm thick ERW.
HTH
Mal

---

quote:

---

Originally posted by Shaw
a quick search for your area turned up this


No results in Eastbourne so your search has widened to East Sussex
DENMAY STEEL & HIRE CO
137, Wellington Rd, Portslade, Brighton, East Sussex BN41 1DN
Tel: 01273 430399
Matches: steel
• 50 Tons Steel Stock • Beams, Angles, Flats, Tubes • Reinforcement Bending • Fabrications, Balustrading • Fire Escapes • Free Local Delivery
Steel Stockholders

Fowle & Co.Ltd
Tremlon House, Menzies Rd, St. Leonards-On-Sea, East Sussex TN38 9BQ
Tel: 01424 444666 Steel Stockholders

J.S Steel Services Ltd
25, Sedlescombe Rd North, St. Leonards-On-Sea, East Sussex TN37 7DA
Tel: 01424 465000 Steel Stockholders

---

I didn't make my chassis so you can all tell me to shut up, hopefully in a nice way - but B&Q do square steel tube, not sure but think about 1 mm wall, and maybe not to your dims.

Maybe worth a look in there - longest pieces would be 2 m but could be quite pricey.

Parker steel do the right types of steel you are after online. But they are quite expensive. However, not as expensive as B&Q though

quote:

---

Originally posted by 02GF74
I didn't make my chassis so you can all tell me to shut up, hopefully in a nice way - but B&Q do square steel tube, not sure but think about 1 mm wall, and maybe not to your dims.

Maybe worth a look in there - longest pieces would be 2 m but could be quite pricey.

---

Steel tube, you want square section ERW. in 1.5mm wall thickness for most of the chassis. If you are really worried about its strength go up to 2mm, which is certainly overkill.

It should be between £5 and £10 for a 6 metre length.

You can always use http://www.metalsupermarkets.co.uk/ if you dont have any other stockholders near you.

David

metal super market wanted £14 for a 6 metre lenght i found a small place about 5 mins from my house and they do the 25x25 2mm thick for £8.50 inc vat for a 7.8 metre lenght skerry steel in blantyre but not to mucjh use for you sorry

[Edited on 9/5/07 by davie h]

Is 1.62mm thickness available? (Pardon my ignorance). Also, can we buy SEAMLESS square sections?

You cant buy seamless square tube. You do not need seamless for any part of the chassis whatsoever.

1.62mm thickness is 16g. But noone really supplies true 16g now, its all somewhere between 1.5 and 1.6mm wall thickness.

They do at Twiggs in Matlock where I get mine. They do imperial or metric but the metric starts at 2mm wall. The imperial has rounder corners for some reason.

quote:

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Originally posted by Peteff
They do at Twiggs in Matlock where I get mine. They do imperial or metric but the metric starts at 2mm wall. The imperial has rounder corners for some reason.

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I agree completely, if you can get the 1.5x25mm it's perfect, I've seen some with 1mm wall which would be good for a lightweight build. That had absolutely square sharp corners.

No such steel available eh (square section seamless). I wonder what Caterham use for their chassis? ERW mild steel?

For the last time, you do not need to use seamless tube for chassis construction. It offers no benefit whatsoever in terms of chassis stiffness or strength.

ERW mild steel is perfectly good enough and will be what all the manufacturers use if they are making spaceframe chassis with square section tubing...

Next people will be telling me using CrMo steel gives you a chassis with a higher stiffness.

Seamless is recommended for rollhoops (required by MSA?) as the tube can split along the weld when its being bent. Though its not all that common.

David