good or bad idea to use plumbers ptfe tape in brake fittings?

If you have any tapered threads I guess so but paste would probably be better. How many tapered threads have you got? I'd bet few or none.....

er, none i think. (?)
they're all banjo fittings, or convex fittings.

i'm using all braided flexi hose throughout too

There's your answer then....ptfe tape or any thread sealants are for tapered threads only. Taper threads rely on the the threads to seal...parallel threaded fittings rely on other means to seal (copper washers, face to face seal, etc.) so don't need sealing on the the threads.

HTH,

Alan

I've never seen ptfe used on brakes before in all my time as a mechanic. Banjo bolts have copper washers.

good stuff
got copper washers for the bajo bolts. thought tape in a banjo fitting was a bad idea anyways, incase it managed to block any fluid holes. wasn't sure about the others. just paranoid (maybe rightly so lol) about doing it all wrong

NO NO & THRICE NO!!!!!!!!!!!!!!!!!!!!

I may have just saved your life!

good! coz i haven't done it
want to get on and order ALL my brake parts tomorrow. really got to get a push on and get this car done (not rushing things like brakes though

The Mk2 Golf brake pressure switch has a tapered thread... the Ford 'T' piece people put it into is a straight thread..... hence the PTFE!

Who needs fully working rear brakes anyway!

Cheers,
James

You should not use sealers on brake fittings. They can react with the brake fluid and cost you money (or blood).
If one of the pieces (block or fitting) are mallable metal you do not need a sealer anyhow. The soft metal will deform and seal. This is how they seal in theory.

Also, it's best to avoid tapered fittings on brake lines. They tend to leak/back off.

Cheers.