How did you age the brass for the blades?

I'm in the making of my very first pair of Steampunk goggles. I've made some prototypes on paper and leather, but until now I'm giving brass and copper a try and I've found quite difficult to curve the metal into the cylindric shape it has to cover the eye.
so I have a question, which is the ⌀ of the cylinder you are using in the 15th picture to strap the metal around? Since I'm more likely to go and buy a piece of solid aluminium to have it always at hand I prefer to have the measurement someone is already using instead of buying something too small or too big, since money is quite a factor for me.
Thank you. All of your work is inspiring and easy applicable in many other context.

I'm afraid I don't quite understand the iris. so the pins for the leaves sit on that outer ring and then there is a second pin on the other side of the ring which sits in the lower plate with slots cut in it? also how would one make the iris close fully? It looks to me like yours still has about a 1/4" hole when its in the most closed position you have. You make the most intricate and amazing pieces! keep up the good work!

all these amazing projects of yours (especially the watch) but no instructables! D: now i will be tormented by these... well, guess i'll try to make my own XD

wow, that cam plate is awesome! how did you make that?

Are the leaves made of metal or wood?

What tool did you use to cut out the numerous blades so perfectly? Amazing workmenship by the way.

Would you mind explaining how you went about making the cam? (The lower, slotted ring.).

Incredible....I've seen plenty of goggles but urs is top dog. One question tho: Did u make the leaves for the iris yourself or did u get them somewhere? What material are they??

http://www.microscopy-uk.org.uk/mag/indexmag.html?http://www.microscopy-uk.org.uk/mag/artfeb07/pj-iris.html

This seems to be a professional explanation of the function and repair of irises, if anyone else is having the same difficulty I was in picturing the inner workings in action.

Great to have some behind the scenes pictures! If you need help with writing english instructions, you could ask from help in the forums.

(I am taking a guess you are based in a non english country?)

i've always wondered on how to do that, thank you very much, it's beautiful

pleaz make a video it's all so confuzing

I made an instructable off of a template like this except it is made of paper, if anyone needs help building this, check out my instructable, just use metal instead of foam core

do you have a template for the blades i can have?

where did you get all your brass parts?

how thick is the brass plate? brilliant idea by the way :)

Nice photo record of a very cool idea!

Let me guess, one end of the iris blade is attached to the outer face ring and the other end just has a peg on it that rides in the second ring? The second ring has the slots cut into it and also has the lever attached to it. correct?

Please post some images when it is completed so we can she what it looks like when someone is wearing it.

Nice to have a look at the process, some explanation text would be appreciated though :)