allu vs stainless steel
 

Hi,
I use a soft panniers, and planning to built (order) an allu or maybe stainlees steel! I came across a donation box in a mosque last week & it was made of stainless steel (the moment I saw it it remind me of an allu panniers!) So now Im thinking if its cheaper, sturdier, a bit heavier why not make them from steel....

comments/suggests

sorry no pics/ still have no camera

Steel yes, stainless probably not.

Basic engineering steel is strong, easy to weld and cheap. It's also heavy and rusts unless coated or painted.

Stainless Steel is less strong, can be brittle, is a real pain to weld, is hard, is very expensive and heavy. You use stainless where corrosion (or heat) is your issue and pick the grade (A2, A4 etc.) based on price versus corrosion requirements and strength/hardness.

Aluminium is relatively strong, can be cheap, can be brittle (eg when bent or vibrated), is very light and doesn't rust when untreated (it gets a protective oxide coat which is ugly but OK).

The traditional solution is a basic steel tube rack for it's strength, possibly with stainless nuts and bolts (avoids rusting together) and alumminuim boxes for the lightness of the big components. You thus combine the features you need. Other combinations risks undesirable features like a rack that will crack when struck and can't easily be welded as a fix.

If Aluminium boxes are an issue, I'd think plastic boxes on a powder coated steel rack, or the rack with soft bags might work better than big stainless parts.

Andy

I would avoid stainless steel. I understand it is not very strong, and is heavy. Ordinary mild steel can be folded into panniers quite succesfully (I have done it with 1mm sheet). Having it powder coated is not expensive and much better than painting.

Alternatively you could buy 2mm 'half-hard' aluminium and make that into panniers. Aluminium is harder to weld but can be pop riveted together which is an arguably better solution anyway as it is easier to fix if you split a seam.

As Andy says, the traditional method is to use a steel rack with alu panniers. It is a proven compromise between weight, strength and fixability.

Matt :)

If I was fabbing some panniers I would go for mild steel. Sure its heavier than alloy but its much tougher (try making a 1mm alu box!), so you use it thinner. Best bit is it's easy to weld so you can do it anywhere, and its pretty stretchy so can dent.

Anyone for Ti? That would be sweet....