Hello, Thought I would pipe up on this one as a long term user and enthusiast of Nisi Sludis and other non-eyeleted, nipple-washers-required rims. The Nisi nipple washers (I have always referred to these as nipple washers and not rim washers... more fun and I like it that, so there!) as I recall, were fairly flat and had a very shallow sleeve protruding from the flat surface that fit into the rim hole but barely came flush or slightly below flush on the visible surface of the rim. Very nice little fittings, and if you have them, I would say they are worth cleaning up, rather than replacing with hardware store stainless jobs. If you don't have them, I'm sure that the hardware store ones are fine, smooth side against the rim, as pointed out previously by another member, and they should be thin enough that they will form to the curvature of the rim with spoke tension. While trying to find something suitable to use with a pair of ARAYA Aero 1 rims (which I think and hope are on topic) last year I found a source for Sapim (Japanese spoke maker) nipple washers at _www.biketoolsetc.com/index.cgi_ (http://www.biketoolsetc.com/index.cgi) (actually listed as Sapim NIPPLE washers, by the way!). These are nicely curved to fit the curvature of most rims, and are oval shaped. Do not order the large ones by mistake as I did the first time, they are HUGE! On my second order I got the small ones which were nice. Unfortunately, the ARAYA Aero 1 rim is really designed for their little proprietary nipple washers, which are like little bars, not much more than a quarter inch long and barely wider than a spoke nipple head, to fit into their fairly sharp aero profile. For these I had to resort to eBay, to find a beat up pair of Aero 1 rims nobody else wanted, from a seller with the kindness to keep all the little nipple washers in a bag with the used rims. This is the end and sum total of my knowledge and experience with nipple washers and how to get them! Good luck and happy wheel building, Tony (Secure Nipples) Winters in Center Moriches, NY USA
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