18 replies to this topic

[miniGTS]

I decided to try and make up some brake lines on my mini. It's a non standard set-up for my car and I thought I would make new lines with steel bundy tubing. I bought a handheld flaring tool that is meant work for steel, aluminium, copper or brass tubing. I've tried to make some flares on offcuts but the first flares were not big enough as I suppect the tubing was slipping in the tool. I then tighted up the tool more on the next attempt but now the flares are forming OK on the head of the flare but the bottom looks weird.

 IMG_20240420_132314.jpg   20.77K   3 downloads

Has anyone else had this sort of thing happen and have you figured out the cause?

[sonscar]

Yoo much tube sticking out of the die?performing the operations in the wrong order?Steve..

[miniGTS]

I used the tube stop bolt first which is meant to ensure correct length and OP1 side of the flare former. Good point on the length though. I'll try it just short of the bolt and see. No harm in testing it.

Otherwise I will just have to remove the subframes and take the tubing to a place that can flare it correctly. Or try to flare kunifer with the tool and see if that works better.

[PoolGuy]

You’re using the turret type of flaring tool? https://youtu.be/hiS...n7xwIeRuwAluuBR

[miniGTS]

A similar type of tool in the way it clamps the tubing and has a flare forming head that gets pressed onto the end of the pipe.
It's this tool.
 Screenshot_20240420_165345.jpg   25.51K   1 downloads

Using the supplied Allen head bolts to clamp the tubing results in the tubing slipping and not creating a good/big enough flare. I then used hex head bolts to tighten it up better. The result is what I posted in the 1st pic in the post.

[Mr Piggy]

It looks to me like the tool bottom right is to position the pipe correctly ready for flaring. So I'd guess you assemble it with the pipe in and the clamp screws nipped up lightly so that when you screw in the positioning tool the pipe can be pushed into the correct position. Then remove it and fully tighten the clamp screws. Then do op1 for a convex flare or op1 then op2 for a concave flare.

[miniGTS]

That's what I've done but end up with a weird looking flare. So either the tool die is dective or I'm feeding too much tubing somehow.

[Spider]

I used to have a similar tool, loaned and never came back !

 

They are a great tool if you only have a few fares to do and also for when working 'on car' in tight places. I've only ever used the standard SAE type though, but made a perfect flare every time. Be sure to oil the threads and not get any oil in the tube !

 

When making the SAE Double Flare, these are made in a single operation, inserting the threaded part of the tool once with the OP1 side IN, that's it, done.

When making an Inverted Flare, first a Double Flare is made in the same way, then the threaded part is turned around with the OP2 side IN and wound in again.

I'm just wondering if you've mixed these operations up here ?

 

Double Flares in a Mini are used everywhere, except on the Rear Flexi Lines and on most Mokes the factory joiners in the side boxes.

The connections to the Rear Flexi Lines and the factory joiners on Mokes need an Inverted Flare.

If you look at the shape of parts the tube is going to seal against, you can quickly work out what type of flare you need to use.

 

I'll just add here too, I've never been crazy about the DIN Flares as they seem to deform the tube just that bit too far. I've seen these fail at the flare, where it's been deformed but can't say I've ever seen an SAE type fail.

 

[miniGTS]

I used to have a similar tool, loaned and never came back !

 

They are a great tool if you only have a few fares to do and also for when working 'on car' in tight places. I've only ever used the standard SAE type though, but made a perfect flare every time. Be sure to oil the threads and not get any oil in the tube !

 

When making the SAE Double Flare, these are made in a single operation, inserting the threaded part of the tool once with the OP1 side IN, that's it, done.

When making an Inverted Flare, first a Double Flare is made in the same way, then the threaded part is turned around with the OP2 side IN and wound in again.

I'm just wondering if you've mixed these operations up here ?

 

Double Flares in a Mini are used everywhere, except on the Rear Flexi Lines and on most Mokes the factory joiners in the side boxes.

The connections to the Rear Flexi Lines and the factory joiners on Mokes need an Inverted Flare.

If you look at the shape of parts the tube is going to seal against, you can quickly work out what type of flare you need to use.

 

I'll just add here too, I've never been crazy about the DIN Flares as they seem to deform the tube just that bit too far. I've seen these fail at the flare, where it's been deformed but can't say I've ever seen an SAE type fail.

 

I've only used the OP1 which is the 1st flare step and should be creating the bubble flare... I used the supplied grease on the tip of the OP1 flarer. I'm wondering if it's just a poor quality tool that I bought or if the bundy is just too hard for it? I'm thinking to get a length of CuNi to test it. If it still fails then I'll probably just remove the subframes again to get the line out of the car and let the pros do the flares for me.

 

I was just trying to avoid the effort of removing subframes to get the line out of the car but it's a small effort considering the consequences of flares that will fail. I will only do the flares myself, whether with CuNi or bundy if I am 100% sure the flares are good... I am current on 0% confident with my bundy tube flares.

[Spider]

I've only used the OP1 which is the 1st flare step and should be creating the bubble flare... I used the supplied grease on the tip of the OP1 flarer. I'm wondering if it's just a poor quality tool that I bought or if the bundy is just too hard for it? I'm thinking to get a length of CuNi to test it. If it still fails then I'll probably just remove the subframes again to get the line out of the car and let the pros do the flares for me.

 

I was just trying to avoid the effort of removing subframes to get the line out of the car but it's a small effort considering the consequences of flares that will fail. I will only do the flares myself, whether with CuNi or bundy if I am 100% sure the flares are good... I am current on 0% confident with my bundy tube flares.

 

As mentioned, I had a similar tool years ago and a friend has one the same as that in your pic above.

They need a bit of awkward grunt to use, but I found, at least for SAE flares, they produce perfect repeatable results every time. It is a tool I would and have recommended many times for someone who only wants to do a few flares. While I have said this, definitely check the tool and if it has a setting gauge, check that too, you can do this by first reducing the amount of exposed tube in the tool and seeing how the flares come out on some scrap tube. Get in touch with the supplier, they could likely give some guidance here.

Also, try the tool using OP2 first, just in case it's been marked incorrectly.

If you are able to get some other tube, maybe from a breaker's yard, to do a further test, it will show if it's the tube you have that's the issue.
 

[weef]

The question of brake tube flaring comes up quite regularly on this forum and always seems to have the same query.

 

NEVER mix SAE and DIN.

 

SAE tube nuts require SAE flares, whether OP1 or OP2.

 

DIN tube nuts require DIN flares, whether OP1 or OP2

 

ALWAYS flare the tube with the correct profile

 

DO NOT trust to luck when flaring tubing, if you are not sure which profile to use ask someone  who knows to show you.

 

DO NOT invert flare everything and hope it will seal

 

As to the tooling you are using there is a big difference in quality of these tools, a good quality one will flare all tubing types with ease producing good repeatable flares whereas an inferior product can be a bit random.

Steel tubing requires a decent quality tool to produce good profiled flares whereas copper or cupro nickel can be flared with good results using tools of a lesser quality.

[miniGTS]

The question of brake tube flaring comes up quite regularly on this forum and always seems to have the same query.
 
NEVER mix SAE and DIN.
 
SAE tube nuts require SAE flares, whether OP1 or OP2.
 
DIN tube nuts require DIN flares, whether OP1 or OP2
 
ALWAYS flare the tube with the correct profile
 
DO NOT trust to luck when flaring tubing, if you are not sure which profile to use ask someone  who knows to show you.
 
DO NOT invert flare everything and hope it will seal
 
As to the tooling you are using there is a big difference in quality of these tools, a good quality one will flare all tubing types with ease producing good repeatable flares whereas an inferior product can be a bit random.
Steel tubing requires a decent quality tool to produce good profiled flares whereas copper or cupro nickel can be flared with good results using tools of a lesser quality.

I agree. I bought the correct tube nuts to match the sae flares that the tool is supposed to make.

I also think the tool I have is poor quality and clearly was overpriced. I am going to test it on CuNi tubing which is copper nickel and if it doesn't create good flares then I will have flares done by someone who has better tooling.

It's just one of those things I hoped I would be able to do easily as it seems straightforward to create the flares.

I think I've done enough research on the different flares and got useful information from members here to know the difference between the flares and correct tube nuts to match the flares and what they turn into.

Brakes is one of those things you just can't get wrong. As I said previously, if I'm not 100% confident in what I'm doing, I'll rather spend the time to have it done properly. But I at least want to try...

[miniGTS]

On the topic of mixing flares and tube nut profile, I found it interesting that some of the original tube nuts on my brake lines that came out the factory look like din on sae flares. The taper on the tube nuts are quite small compared to the tube nuts I bought recently. But I guess it has some degree of a taper whereas the din is very flat in comparison. Also interesting is that M10x1 tube nuts on the original brake lines had din flares.

[Spider]

To hopefully clear the air, I've posted some info in FAQ;-

https://www.theminif...ngs-and-flairs/

 

When I get some more time, I'll post one up on making lines.

[miniGTS]

I've managed to get some better flares with my tests. I've identified the problem and now able to make more consistent flares. It seems that the stop bolt supplied in the kit is slightly too short which resulted in too much tubing entering the die. So as was suggested by Steve, it seems to be too much tubing causing it to "bunch up" in the die.

 

So with slight adjustment, flares look ok?

 

new flare on the left orignal flare on the right

 old-new-flares.jpg   26.58K   2 downloads

 

 

Flare seated in the M10x1 SAE tube nut that goes into my dual master cylinder.

 new-flare-seat.jpg   21.36K   1 downloads