recessed brake nut in a carbon fork

The hole on the fork is smaller than the diameter of my brake nut. Any ideas? I'm using a 8mm standard nut and can't see any smaller diameter ones. Maybe see if someone can machine a half mm off the diameter?

Drill the fork.
Or use one of these

Is it OK to drill a carbon fork?

i really wouldnt bother.

its not a fibrous form of alloy so if done badly, as well as looking shit will also affect the structural integrity...endless choice of drilled carbon forks out there, so its just not worth the risk

sell undrilled fork, buy drilled fork

The fork is already drilled/ has a hole for a brake nut.

yes, during the manufacturing process...to drill it at home with some power tool simply isnt worth the risk and you shouldn't be promoting that

I wouldn't risk it either. There is a possibility that the fork may become damaged and cause a weakness. I know that if I was to suffer a carbon failure due to a weak spot I wouldn't want it to be the fork.

We use a company that specialises with sheet metal, they might have a lathe and can take half a mm off the diameter. The hole in the fork is 8mm same size as the nut

Just called into my LBS and they wouldn't hesitate to drill out a carbon fork! Other than that they had no ideas......and really weren't interested tbh. So not a shop I would recommend.
Think I'll get a nats of a mm.machined off

The hole on the fork is smaller than the diameter of my brake nut. Any ideas?

Is it painted? If so, using an 8mm hand reamer to scrape off the excess paint probably won't even touch the actual carbon fibre.

There's more spare material in the fork crown than there is in the nut, so I'd favour making the hole bigger rather than making the nut smaller. If you take the nut down to 7.5mm, you're reducing the cross sectional area by about 28% on a component whose resistance to tensile load is all that's keeping your front brake attached.

No its got the weave showing, suppose it is varnished though

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The lacquer tends to be pretty thick, especially if it builds up in the recess. Scraping or sanding back to the fibres is a common #weightweenie trick

Just to get the nut in the hole I've tapped it in gently with a hammer and am trying to wind it in with an Allen key. It's hard but going in slowly

Years ago I had a pair of steel forks do the splits on me hence why I am worried about drilling.

Carbon forks are stronger than steel by regulation, the EN14781 impact test uses 78% more energy if the fork has any carbon fibre parts compared with all-metal forks.

I remember that some of those ouso forks where faulty a few years back.
I would check the recall and date first.

@pacef8 thanks for heads up. I'll try and get the serial number of the forks. Have just Google it and it's from about 2007

Phew, 43mm forks but the serial number is 01750

You get to keep all your teeth then.

Yes, but judging from the serial number they are early in productin