406 handbrake, what shoes do you use?

[PhillipM]

Would have thought that rally linings would be harder, I think a softer compound is what's needed - just a thought.

Peter

That old thing of softer/harder compounds went out of the window about 30-40 years ago when it comes to brake linings, pads and discs don't work like that any more, they run on chemical adhesion as much as mechanical grip, some of the highest bite compounds you can get now are incredibly hard ceramic based compounds.
Rally linings are designed with a high initial bite when it comes to hand-brake shoe compounds to allow the wheels to be locked. That does result in poorer release as it generally means an aggressive bond, but that's not really an issue for our brakes anyway because they're not used for hydraulics.

[jasper5]

Mine are adjusted correctly, the handbrake will hold on 4 clicks. It's just not very good.

(I only have a decade of experience with building brake systems from scratch for multiple championship winning rally cars)

I have to fix cars for the general public who expect their handbrake to work properly day to day, especially as they are paying me to do that.
I am successful in doing that!

Building brake systems from scratch for a specialist situation is a completely different scenario and cannot be compared!

[PhillipM]

So, you're telling me everyone on here bar you cannot make the handbrake work properly, just because you've worked as a mechanic for a while?
Even though a massive amount of MOT failures for 406's are on handbrake efficiency? What are all those mechanics doing wrong? Or are they the wrong sort of mechanic?

Of course you can make it pass an MOT, anyone can do that, mine's setup as good as it can be - it'll hold on a hill with 4 clicks, but it still takes 3x the force my 306 did to do that, and you don't have much force spare because as I said earlier - you can feel it start to just stretch the cables and linkages.
I don't want that, I want a good handbrake, one that has enough power to lock the rear wheels, because I use my car on gravel and mud tracks, and in heavy snow over the winter, where you need the option to change the brake bias- not one that passes the frankly laughable MOT test. It's not possible with the standard setup, the leverage reduces the more pressure you apply, it's basic physics the way the system is arranged given the geometry of the brake expanders and the handbrake pivot - that's why the 406's handbrake takes so much more force than most to start with.

If you think cleaning up and swapping parts for a few years in any way compares to physically designing and making your own calipers, discs, pads, uprights, hydraulic systems, etc, then I'll leave that argument right there. Here's a hint. I do cars for the public too. Including general mechanical repairs. Shock. Horror.

[jasper5]

So, you're telling me everyone on here bar you cannot make the handbrake work properly, just because you've worked as a mechanic for a while?
Even though a massive amount of MOT failures for 406's are on handbrake efficiency? What are all those mechanics doing wrong? Or are they the wrong sort of mechanic?

Of course you can make it pass an MOT, anyone can do that, mine's setup as good as it can be - it'll hold on a hill with 4 clicks, but it still takes 3x the force my 306 did to do that, and you don't have much force spare because as I said earlier - you can feel it start to just stretch the cables and linkages.
I don't want that, I want a good handbrake, one that has enough power to lock the rear wheels, because I use my car on gravel and mud tracks, and in heavy snow over the winter, where you need the option to change the brake bias- not one that passes the frankly laughable MOT test. It's not possible with the standard setup, the leverage reduces the more pressure you apply, it's basic physics the way the system is arranged given the geometry of the brake expanders and the handbrake pivot - that's why the 406's handbrake takes so much more force than most to start with.

If you think cleaning up and swapping parts for a few years in any way compares to physically designing and making your own calipers, discs, pads, uprights, hydraulic systems, etc, then I'll leave that argument right there. Here's a hint. I do cars for the public too. Including general mechanical repairs. Shock. Horror.

Well, I can't say any more than the fact that when I service the handbrake on a 406 it works...end of!

As for your last paragraph...I said that you can't compare your situation to the 406 handbrake situation and I never would, yours is a specialist scenario whilst the 406 handbrake is a day to day problem.

I think we should both leave it there as stalemate is where we are at!

Best regards.

[binnzy]

Do not do this it is not the right thing to do, go to an engineers supply buy a tin of belt dressing spray a thin coat on the shoes before the mot, the shoes will stick like sh%* for a few days

[PeterN]

... or squirt some water in them the previous day...

Peter

[steve_earwig]

Oh yes, something very wrong with the design, I think most of them end up just taking out the slack, the bit at the end where it goes tight is the mechanisms starting to move. It was a similar layout in the old yoyo (the new one has park so I've never worried about it), that was so good I think the car would roll in its nose first. The only difference was the front cable stops just before the rear diff, then two separate cables to the brakes. The 406 set up, with one canle going all the way to one side and a shorter one tee'd off it, is very reminiscent of the set up on the Avengers (maybe not such a coincidence when you think who ended up owning Hillman/Chrysler Europe).

I think there's a lot to be said about friction material, I had mine relined with a softer material and it did improve matters, for a while anyway. I had the option of some even softer stuff but I never got around to it. I did notice the box my new shoes came in said they also fitted certain tiny Fiats, another case of one size fits nobody perhaps.

Re. the MOT thing, cheapest way is to pull the disks off and scuff everything up with some 50 grade emery paper, then they should just last long enough to get a ticket.

[PhillipM]

Some of that, like you say, is down to the friction from running a single line with a splitter, you end up with a normal force at the split that's acting directly on the sheath, it doesn't help, but the geometery of the expanders and handbrake pivot are the worst issues (if you look at the handbrake, the leverage actually decreases the further you move it. Arse backwards designer.)
But given shoe relining is cheap, it's just easier to start there with some aggressive compounds.

Or just swap a hydraulic handbrake in

[steve_earwig]

It's crossed my mind before but ISTR hydraulic handbrakes are not MOT-able - some nonsense about the system loosing pressure and having no brakes at all in an emergency. How electronic ones are allowed is anybody's guess (huge bribe somewhere down the line?)

That makes more sense, having compared the two I really couldn't see much difference, just the cable arrangement which I wasn't sure about as the Avenger handbrakes worked.

An old neuron farts into life: Avenger handbrakes had a rod instead of the second cable, that part of the handbrake expanders poked through the backplate. The automatic adjusters were similar to the 406's, with a steel "finger" turning them if they had play enough and thereby taking up the play. They were crap.

406 handbrake levers come with either the cable at the top or underneath, fitting seems random. I wonder if they're any different.

Worth greasing the feck out of the handbrake lever?

[PhillipM]

They're fine so long as you retain the cable setup too, whether on a seperate handbrake or linked the the hydraulic mechanism as a backup - we have to do that with the safari cars as they do plenty of road miles so need an IVA/MOT.

Bit overkill for a 406 though

[PeterN]

Would have thought that rally linings would be harder, I think a softer compound is what's needed - just a thought.

Peter

That old thing of softer/harder compounds went out of the window about 30-40 years ago when it comes to brake linings, pads and discs don't work like that any more, they run on chemical adhesion as much as mechanical grip, some of the highest bite compounds you can get now are incredibly hard ceramic based compounds.
Rally linings are designed with a high initial bite when it comes to hand-brake shoe compounds to allow the wheels to be locked. That does result in poorer release as it generally means an aggressive bond, but that's not really an issue for our brakes anyway because they're not used for hydraulics.

You learn something new every day - only I usually forget it soon after . My brake lining experience comes mainly from the '50s so I suppose things would have changed since then, I know being young I used to punish the brakes on my Vauxhall Cresta and they would practically fade out after a while, no servo in those days of course. Thanks for the info anyway - interesting.

Peter

[jasper5]

So, you're telling me everyone on here bar you cannot make the handbrake work properly, just because you've worked as a mechanic for a while?
Even though a massive amount of MOT failures for 406's are on handbrake efficiency? What are all those mechanics doing wrong? Or are they the wrong sort of mechanic?



If you think cleaning up and swapping parts for a few years in any way compares to physically designing and making your own calipers, discs, pads, uprights, hydraulic systems, etc, then I'll leave that argument right there. Here's a hint. I do cars for the public too. Including general mechanical repairs. Shock. Horror.

If you are so good at making stuff work perfectly, where is your solution that everyone can copy to repair their handbrakes.
At least my solution works!

I'm still waiting, I thought I might have been reading about it by now

[PeterN]

I can only repeat what I said before, it must be down to brake lining material because I have tried everything else. There are three mechanics locally and they all say 406 hand brakes are useless so if Mintex linings are the answer I shall be delighted as I have some in stock. Otherwise the 406 is a super car, this is the only fault I have found.

Peter

[trufflehunt]

My handbrake has always been fine.
.
.
.
.
.
So far.

Or to be exact. It needs the last click to be able to hold the car on a slope.
It passes the MOT Ok,
On that basis , I decided to leave well alone.

Must say, on an everyday car, that isn't being hurled down the side of a Welsh mountain on a rally, or doing handbrake turns....
I can't in any way see how special brake linings are relevant.

[PeterN]

Softer lining material will have a better friction coefficient but wears quicker which doesn't matter at all for the purpose discussed.

Peter