[CR] Recessed brakes frames and using non recessed brakes

I had brake nut worked loose and disappear while riding. I had used a Rivendell nylon insert for non recessed nutted brakes on a frame required recessed nuts. And it failed while riding. I found that a tube valve round nut fits right in and all you need to do is file away threads and coat with a clear paint. than mount non recessed nut on brake bolt. Thanks Charles Nighbor Architect Walnut Creek CA USA