I need a M12 x 1.5mm male brake union for 3/16" pipe. Help!

I need a M12 x 1.5mm male brake union for 3/16" pipe. Help!

Author
Discussion

montyjohn

Original Poster:

175 posts

59 months

Monday 22nd November 2021
quotequote all
Hi all,
I've been trying to get hold of two M12 x 1.5mm male brake union for 3/16" pipe for a master cylinder using a double flare and not getting anywhere.
Easy in the US. Loads of shops selling them. But the postage cost and time are a bit painful

These guys (http://www.carlton-hydraulics.co.uk/) are the only sellers I have found in the UK but they are not keen posting to a member of the public for such a small order - Product ID - BQ9193

I live in Purley (CR8) - South London.
Does anyone know where I can buy these, online or store?

So far all calls to local shops don't stock them.
They can only sell me M12 x 1mm male unions (wrong pitch).

Any suggestions appreciated

stevieturbo

15,835 posts

220 months

Monday 22nd November 2021
quotequote all
What car ?

M12 is very odd for a brake fitting, even more so x1.5

I'm sure someone with a lathe could turn you one up easily enough or cutting down a M12 bolt.

montyjohn

Original Poster:

175 posts

59 months

Tuesday 23rd November 2021
quotequote all
stevieturbo said:
What car ?
It's a kit car.
But the brake m/c is from a Mondeo MK5.
I have the unions that came with the m/c but they are for 1/4" pipe.

The other method would be to have a short length of 1/4" pipe, and then a reducer, but then that would mean buying a new flaring tool, and it would look a bit of a mess so that's Option C I think.

Edited by montyjohn on Tuesday 23 November 10:34

E-bmw

6,636 posts

125 months

Tuesday 23rd November 2021
quotequote all
I would say check again exactly what you need as M10 x 1.0 is the most common, in fact I can't remember the last time I saw something different that wasn't american.

montyjohn

Original Poster:

175 posts

59 months

Tuesday 23rd November 2021
quotequote all
E-bmw said:
I would say check again exactly what you need as M10 x 1.0 is the most common, in fact I can't remember the last time I saw something different that wasn't american.
I know right. Although M12 is pretty common on m/c. But are usually M12 x 1.0mm.
So I blindly ordered the M12 x 1.0mm to find they don't fit.

Here they are side by side. You have to guess which is which.



I haven't got any thread gauges, but measured 5 threads with calipers at something like 7.4mm. Pretty hard to be precise, but close enough to 1.5mm pitch.

EDIT

Here's an M10 * 1.0mm next to them




Edited by montyjohn on Tuesday 23 November 10:36




Edited by montyjohn on Tuesday 23 November 10:40

montyjohn

Original Poster:

175 posts

59 months

Tuesday 23rd November 2021
quotequote all
Just thinking, it could be 1/2" UNF, but they surely wouldn't use that on a 2016 Mondeo?
Also the pitch for 1/2" UNF is 20 TPI according to google so that would be 1.25mm.

GreenV8S

29,127 posts

257 months

Tuesday 23rd November 2021
quotequote all
montyjohn said:
I haven't got any thread gauges
You can use any ordinary bolt with the correct thread pitch as a thread gauge.

E-bmw

6,636 posts

125 months

Tuesday 23rd November 2021
quotequote all
Never seen any like that before.

Ref. Thread gauge.

Quite easy if it is 1.5 rather than 1.0 three threads on one = 2 threads on the other.

stevieturbo

15,835 posts

220 months

Tuesday 23rd November 2021
quotequote all
And will the master even accept a 3/16" pipe/flare, if the intended fitment is 1/4" ?

Routing 1/4" pipe to a suitable adapter then 3/16" would be better.

Although I don't think I've ever seen any UK car use 1/4" brake pipe.

montyjohn

Original Poster:

175 posts

59 months

Wednesday 24th November 2021
quotequote all
stevieturbo said:
And will the master even accept a 3/16" pipe/flare, if the intended fitment is 1/4" ?
This is a great question and the first question I had.
I offered up a 3/16" flare to the m/c when I first realised the problem and there seems to be plenty overlap between the flare and the cone on the m/c.
The hole in the cone is 3.9mm dia, compare with an approx ID of 3/16" pipe of 2.9mm. The dia of a flare is about 7mm.
So it should seal, but I have no experience to confirm this.

stevieturbo said:
Routing 1/4" pipe to a suitable adapter then 3/16" would be better.
I may end up having to go down this route anyway to to avoid the wait of shipping across the pond.
My only problem is:
2 x reducers (£34) - https://www.ebay.co.uk/itm/362045651225
1m of kunifer is £7, at least that's cheap.
So I'm looking at £40 + garage time for the 1/4" flares. I could buy the tooling, but I need one end to be bubble, and one double, and I'm probably never going to need /14" again. Hopefully.
A new m/c might be cheaper.

I've found garages in North Wales really helpful, but in South London I've always been disappointing. I'm sure there are helpful ones out there, I've just not found them.

I once asked for a new resister to be soldered onto a AC control unit, I had the resister in hand, autos wanted £300 for this job.
I also took a pair of control arms into a garage to press out a pair of bushes. £80 quote. They just looked up the book time and weren't interested that they don't need to remove or refit the control arms.
Walked away on both occasions and did the work myself.

I think one off work to help the DIYer type isn't worth their time when there's good money to be made swapping people disc pads and tyres.
I'll try anyway and see how I get on.

richard sails

805 posts

232 months

Wednesday 24th November 2021
quotequote all
Try Automec, they have hundreds of fittings

https://automec.co.uk/

would this one do?

https://automec.co.uk/collections/fittings/product...





stevieturbo

15,835 posts

220 months

Wednesday 24th November 2021
quotequote all
Really...if it is indeed M12 you need, and regular 3/16" pipe will actually work...

Buy a couple of M12 bolts, and have someone adjust them to become a brake pipe fitting. It should be very easy to do.

Ralph should be able to knock you them up quite easily from a variety of materials.

https://www.componentengineering.co.uk/

montyjohn

Original Poster:

175 posts

59 months

Thursday 25th November 2021
quotequote all
richard sails said:
Thanks for taking a look, but I tried them already and they don't have a 3/16" version of that union.