Nut Brakes into Allen Key Drilled Frame

Any help appreciated with this one. I want to mount a set of brakes with a long pivot bolt and a nut to fix them onto a frame drilled for allen key brakes. Due to the oversized hole at the rear of the fork crown and front of the brake bridge, they will not be secure. Does anyone know a work-around or a conversion piece to allow this combination to work with the brakes properly secured?

Thanks in advance.

Usually the rear goes to the front.

And the old front is rethreaded and cut, or a new bolt is installed.

?

Thanks guys.

DMC, the rear length is good for the front and I'm looking at tap and die sets on the bay (unless anyone has an M6 die I could use for about 5 minutes...).

Pifco, thanks again but a washer will still allow the bolt to move in the hole at the rear of the fork crown and front of the brake bridge when the brake is applied. It doesn't solve the problem unfortunately.

If you don't want to butcher the brakes, drill out the socket head fasteners used with recessed brakes so they pass over the thread on the nutted brakes, then use the washer and nut as usual - the ex-socket headed nut becomes a sleeve to support the calliper stud. Obviously easier if you have some alloy fasteners rather than the usual steel.

Thanks RDC, that steers me back to what I wanted to do to start with. Now I just need to find a pair of alloy allen key nuts. Does anyone know where to get them from? I ordered some steel ones off ebay but definitely I'd rather be drilling alloy ones.

Dick, I have a pair you can have, if you're in a hurry I can post them or drop them off later this week? cheers,H

H, Later this week is fine. I owe you a beer, if that's your tipple. D