# 1/2 Moon washers



## bigfella (4 May 2009)

After a couple of these washers for my project on at the moment. Can't seem to find any in the UK.

http://cgi.ebay.co.uk/DIA-COMPE-BIC...hash=item380073762826&_trksid=p3286.m63.l1177


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## mickle (5 May 2009)

I'm sure I have some in't workshop. You'll be wanting two I assume?


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## bigfella (5 May 2009)

Yes please, its just where I have drilled the rear brake bridge to accommodate the later style brakes with recessed bolts. I guess without these it does not give much material for the bolt to tighten against.


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## mickle (5 May 2009)

Hmm. You'll have to drill one out to accept the back-nut as they are drilled to accept the bolt. You're into mild bodgineering territory here, there's more to a stay bridge designed to accept a recessed nut than the diameter of the hole. They are often reinforced with a brazed in sleeve and/or have flats to accept the brake and nut. 

I suspect that you'll find that adding the two concave washers will make the stay bridge too deep to accept your standard length back-nut. I have a few Campagnolo long back nuts in the workshop which should reach.

However, purpose made stay bridges have a small hole to receive the brake-centre-bolt and a larger hole to accept the recessed back-nut so another wee issue is that by drilling out the hole to accept the back-nut you'll have made the brake-centre-bolt hole too big for the brake-centre-bolt. There will therefore be a tendency for the brake to slip. You're relying heavily on the fit of the back-nut in the hole to keep the whole thing from moving downwards when you apply the rear brake. 

What you require is a concave top-hat washer to simultaneously provide an interface between the flat of the brake and the curve of the stay bridge _and_ to sleeve up the centre bolt to fit the new stay bridge hole. 

Unfortunately no such thing exists


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## bigfella (5 May 2009)

Thanks Mickle, great advice. 

Its exactly what I'm trying to do - I have already drilled out the rear of the bridge and test fitted some old "recessed" type brakes to test. I did not drill the whole bridge out to 8mm, I left the outer hole standard size and managed to get the drill to the rear of the bridge. 

I found that the back nut was too long and that as the bridge is tubular I need some 1/2 moon washers for the caliper to bolt against a flat surface. I will indeed need to drill one of them out to accept the back nut but if this is approx 8mm as is the hole to the rear of the brake bridge I thought this would be fine? As long as the back nut is long enough to pass through the moon washer and the first hole in the bridge. The smaller diameter bolt itself will only pass through the second hole and undrilled 1/2 moon washer. Therefore should give a snug fit?

Hope that makes sense!

Its a really nice frame, just a shame it doesn't have the newer style rear bridge. I have a brand new set of Campy Mirage double pivot brakes to fit. 

Whereabouts are you located, guessing Scotland due to the use of the word "wee"?


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## mickle (5 May 2009)

York the noo!


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## bigfella (5 May 2009)

LOL, bit far then - thought I could always pop over if you weren't too far away.

Please let me know if you find the washers and longer nut.

Cheers


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## mickle (5 May 2009)

Found. The washers are a bit mangy but they'll clean up ok. I couldn't find any carbon ones..

PM me your address.


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## bigfella (5 May 2009)

Many thanks cheers.


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