For those who are interested, the shelves seem to be able to handle a fair amount of weight. Mr fishie here weighs about 300g and wasn't causing any trouble whilst sitting there.
I can't remember what weight paper I used - I think it was around 300gsm because that was all I had, but I reckon you can go a bit heavier. I've uploaded some PDF templates if anybody wants to try: narrow(80mm), medium(115mm), wide(150mm).
*AKA Kirin Notebook, the name I gave my blog back in the day when I had a thing for giraffes (’Kirin’ - ‘giraffe’ in Japanese).
About
I am a Melbourne based textile designer and co-owner of Ink & Spindle, a boutique, organic and sustainable yardage screen printing studio located in Kensington.