Generally, these metal shops use low quality steel. Whereas aluminium is the first choice for bikers because of its lower weight.
While every shop will say "yes yes, we can do this for you, no problem", you will find that not many of them stock aluminium. Insist that this is what you want - you'll waste less time this way.
I had some made in Cochi, in the south. On the good side: they were cheap yeah. I think 25USD each. They were handmade, without welding, each corner being tucked-in by little flaps and hammered. They were perfectly waterproof. There must have been twenty hours work in each box. Easily.
But be aware, this hand-made method only works on 1mm aluminium. Any thicker and the worker need tools beyond a hammer.
Aluminium welding - necessary for the thicker stuff - costs money for the gases. So the price may not be as competitative as you hope.
Generally, I would say 1mm is too thin for any box of size - just not strong enough. The larger of my boxes developed splits.
I would recommend 1mm for smaller boxes - for tools perhaps - in places that are not going to get big impacts when you drop the bike.
Touratech use 1.5mm, but every long distance biker I ever met with TT boxes had had to re-build them 'cos they are too thin.
Also, the quality of the ally will be lower in India most likely.
If you can find an aluminium welder in India, then you are in luck - they can weld to any width. There must be some, although I never found one. Try airports and boat yards would be my advice.
A 2mm thick ally box, with a reasonably fitted lid will be fine, although I would make the inside side (where it attaches to the rack) out of 2.5mm for extra strength, particularly if the boxes are big.
Lastly, remember that any design/discussion/fabrication/purchase process is going to take a week or two in India. Like most places in the world, India works on the 'top of the pile gets first attention' system. So it is best to check in daily on the shop, or your work will go down that pile.
Is this how you want to spend your holiday?
Hmmm, a bit too negative this post - that wasn't my intention when I set out, but it is best that you know your options.
So happy welder hunting,
[This message has been edited by Simon Kennedy (edited 28 October 2005).]
Around the world 2000-2004, on a 1993 Honda Transalp