Brake pipes DIN and SAE single? Enlighten me!

Brake pipes DIN and SAE single? Enlighten me!

Author
Discussion

richard at home

Original Poster:

331 posts

133 months

Tuesday 5th October 2021
quotequote all
Having looked at the two different types of flare, DIN and SAE single, I can see that SAE single is like a bubble flare and DIN has a flat area on the pipe side.

Am I right in thinking a SAE flare needs an SAE union nut to go with it, with a corresponding chamfer to accept the shape of the bubble flare?

A DIN flare needs a DIN nut that has no or a very slight chamfer?


Which should I use to remake these pipes taken out of an XJS rear caliper? 2 look like DIN but the middle looks a little more like a SAE.





If I am using new nuts which have a tiny, slight chamfer, should I use a DIN flare?

Is there a difference between DIN and SAE in the shape and dimensions of the flare at the open end of the pipe?


Help!

GreenV8S

30,884 posts

299 months

Tuesday 5th October 2021
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It might be an issue for steel pipes but I'd have thought that brass pipes would form to fit whatever fitting you clamp on them - and if they don't, it wouldn't take long to anneal the end so that they will.

stevieturbo

17,775 posts

262 months

Tuesday 5th October 2021
quotequote all
certainly the left and right images do not look like original items, and indeed the flare itself looks pretty poor.

The middle looks a lot better.

Must admit, never really looked into the differences between DIN or SAE though

Dave Brand

938 posts

283 months

Wednesday 6th October 2021
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stevieturbo said:
Must admit, never really looked into the differences between DIN or SAE though
Don't know about the flares, but the thread may well be different.

DIN will be Metric, SAE can be either UNF or Metric. I don't know whether DIN & SAE Metric are the same, but I know from experience that DIN & UNF aren't? Who'd have thought that a 1973 Escort Mexico would have Metric brake pipe fittings. . . that's one wheel cylinder knackered, then!

paintman

7,818 posts

205 months

Wednesday 6th October 2021
quotequote all
If you're forming your own pipes using Cunifer or similar don't totally crush the ends when forming. Usually seal better when there is still some room for compressing to fit when reinstalling.

Your nuts don't actually look that bad so to get round the 'what is....' issue I'd be inclined to reuse them. Better to use a proper fitting brake pipe spanner than trying to do it with an open ender.

Dave Brand

938 posts

283 months

Thursday 7th October 2021
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paintman said:
Better to use a proper fitting brake pipe spanner than trying to do it with an open ender.
My brake pipe spanner ranks very highly in my "best tool I've ever bought" list!