Flexi brake pipe

[Mat196]

I'm changing the rear flexi brake hoses, the union to the steel pipe is heavily corroded.
See pics below, (Fig 5) is the flexi hose, (fig 3) is the steel pipe.
I've had to cut the old joint away due to being corroded to death.
I am now trying to flare the pipe fig 3 to attach back into the flexi through the retaining spring (fig 6). However I have flared it like any other pipe previous but this is so much tougher (maybe because it's steel & not softer copper) I cannot get it to seal.
I've been trying for hours but no joy I build it all back up and the fluid leaks out of the union, not the thread part the pipe part.
Any tips on how to flare this tougher steel??

 

[Mat196]

I will try to get a photo of the flare I completed tomorrow when its light.

 

[Sidrick]

You must have extended the steel pipe with a copper bridge section, no?!

 

[Mat196]

No? I'm trying to flare the steel part to go straight into the flexi like original?
If i extended the steel pipe with a bit of copper pipe I'd still have the problem of trying to flare the steel pipe to join the copper?

 

[neilA4]

you need a flaring tool for steel pipe, about £35 on Amazon.

The copper flaring tools are useless on steel.