Thread: Cold Rolled Steel Sheet Sizes Auto Panels

Over about 3mm is into plate.

After 1.15mm you're really looking at Hot Rolled sheet from 1.6 to 3mm. If it is just a bracket it may not matter if it is hot rolled. You can knock the millscale off it with a flap disc, sand blaster or whatever if needed. Also, if it is just a simple bracket you can also get bright mild steel flat bar sections which potentially may work.

Tombie may tell you more, he makes the stuff.

Originally Posted by Slunnie

Over about 3mm is into plate.

After 1.15mm you're really looking at Hot Rolled sheet from 1.6 to 3mm. If it is just a bracket it may not matter if it is hot rolled. You can knock the millscale off it with a flap disc, sand blaster or whatever if needed. Also, if it is just a simple bracket you can also get bright mild steel flat bar sections which potentially may work.

Tombie may tell you more, he makes the stuff.

My company does - I just run the raw extraction of minerals and processing.

Lionel just do a Google search for sheet metal Australia. All the sites have listings.

How big is said bracket? Can you post a pic of location?

1.15mm is usually the limit for Cold Rolled.

Galv / Zinc will go 1.55mm

1.15mm if bent / profiled correctly will usually be more than adequate.

Depending on dimensions needed Hot Rolled would be adequate, can be had from Bunnings etc 1.6mm upwards

Hello Slunnie, Tombie, and Others,

Thanks for your detailed reply Slunnie.

The "bracket" - for want of a better term, bridges the horizontal space between the firewall, the upper and lower plenum, and the intersection of the door pillar; along with the sides or "posts" of the windscreen. It appears to be made of a thicker material than the firewall - or the plenums. It is also the point where the top of the mudguards get fitted to. This could explain why this panel appears to have a thicker gauge. The panel also has more folds and ribs when compared to its neighbouring panels.

There is also a couple of "C" shaped brackets that act as the front mounting points of the cab to the chassis. These are also too badly rusted to be able to tell what their original thickness were. However, they appear to be approximately the same thickness of the "bracket" described above.

The cab mounting points would lend themselves to be re-fabricated in thicker hot rolled steel.

Kind regards
Lionel

For semi structural it was likely 1.6mm

Hello Tombie,

The part/panel/bracket is 300 mm long by 160 mm wide. Why I am calling it a bracket is because I have to take this section off to be able to separate the firewall from the lower plenum and the side of the door pillar.

It is also the only panel that has a number of the pressed "dimple" circles for reinforcement that I have come across in this vehicle so far. The section has three sides that are folded 90 degrees above the rectangle's mostly horizontal plane. These folds join with the door pillar, plenum and firewall respectively. The fourth side that faces the outside of the vehicle is folded at a 90 degree down from horizontal where it joins with the inside of the mudguard. Well, it would if this edge was not eaten out with rust. I will have to get a non-eaten out mudguard to mount so I can work out the exact curve of where the horizontal panel's edge is meant to come in contact with the inside of the mudguard. In this section of the vehicle all I have is a big rust hole where all the panels intersected.

Are there any problems with butt welding cold rolled to hot rolled steel sheet? Does the difference in processing also involve differences in their composition that could affect their compatibility to weld? The panel was spot-welded and brazed to its adjoining panels.

Kind regards
Lionel

Originally Posted by Lionelgee

Are there any problems with butt welding cold rolled to hot rolled steel sheet? Does the difference in processing also involve differences in their composition that could affect their compatibility to weld? The panel was spot-welded and brazed to its adjoining panels.

The differences between them don't prevent them from being welded together successfully.

As Slunnie has said, you’ll have no problems welding the 2 materials.

Like any welding, site prep and proper technique is all that is needed.

A good Tig is worth its weight in gold, failing that a good Mig will get the job done nicely.