Classic cars forum & vehicle restoration.

[ka]

To cut a long story short, I am upgrading from SLS to TLS. I have looked at many pictures of TLS set-ups, but they all seem to differ.
The shoes I am using have an 'offset' lining, ie, it is nearer one end of the shoe than the other. I have looked at the logic of mounting shoes both ways round, lining closer to end of shoe nearer the wheel cylinder, and vice-versa.
Any one any advice?
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KA

Better three than four.

[V8 Nutter]

I don't know but I would have thought there was a lot more to it than just changing the shoes.

[Roger-hatchy]

Twin leading shoes should have a moving piston at the leading end of each shoe, IE A single pistong either side of the set up, one for each lead.

As to the lining further back from the leading edge, I think it is to do with leverage and travel.

All brake shoes I have ever seen, Both SLS and TLS, have the lining toward the rear of the shoe away from the rotation.

Someone with a bit more technical knowledge should have a better answer

[Jim.Walker]

Over years I have thought long and hard about lining position relative to actuating pistons and have even, without success, searched technical literature for the answer.
It does not help that Manuals illustrations differ from car to car.
However. In my mind it stands to reason that the lining will wear most on the end closest to the pivot and moving the lining closer to the cylinder will even out the wear pattern.
Also, the closer the lining contact with the drum is to the cylinder the greater will be the servo (leading shoe) action.
Very simply, the greatest "leading shoe" effect will occur where the greatest (tangential) friction is furthest away from the pivot. Like pushing on a longer lever.
I realise this does not answer your question and I might have completely overlooked other arguments.
I have never been very happy with this topic.
Jim.
_________________
Quote from my late Dad:- You only need a woman and a car and you have all the problems you
are ever likely to want". Computers had not been invented then!

[Jim.Walker]

Over years I have thought long and hard about lining position relative to actuating pistons and have even, without success, searched technical literature for the answer.
It does not help that Manuals illustrations differ from car to car.
However. In my mind it stands to reason that the lining will wear most on the end closest to the pivot and moving the lining closer to the cylinder will even out the wear pattern.
Also, the closer the lining contact with the drum is to the cylinder the greater will be the servo (leading shoe) action.
Very simply, the greatest "leading shoe" effect will occur where the greatest (tangential) friction is furthest away from the pivot. Like pushing on a longer lever.
I realise this does not answer your question and I might have completely overlooked other arguments.
I have never been very happy with this topic.
Jim.
_________________
Quote from my late Dad:- You only need a woman and a car and you have all the problems you
are ever likely to want". Computers had not been invented then!

[ka]

The more you think about the logic of the leading edge, trailing edge, the more you get confused.
I have looked on web sites, and handbooks and they all differ. To try and get a definitive answer I have done two things,
Took the TLS brake to bits on my motorbike, looked at a Minor 1000 brakes with the drum off.
These both at least agreed.
The shoe has an metal base, and a lining (mine are the devil word 'asbestos') riveted together. The lining is mounted off centre, ie it is nearer the end of the metal base to one end than the other. Both the examples I have looked at have the gap between the metal base, and the lining at the wheel cylinder piston end, with the shoe/metal base/no gap at the pivot end.
I will find out soon as I have one 99% complete, ready to start on the other.
_________________
KA

Better three than four.

[jessejazza]

[jessejazza]

[ka]

The brakes are for a Three-wheeled Morgan, a later one where the front wheels only are braked (hand-lever only for the back wheel)
I upgraded the brakes from rod to SLS hydraulic 10 years ago (TLS was not an option at the time, for reasons too long to go into), but now these reasons are not prevalent, so TLS beckoned.
I have now completed the work, and placed the shoes as shown in the Morris handbook, ie, the lining is biased towards the fixed pivot point giving the necessary servo effect when the brakes are applied.
All is well in the Morgan camp, smooth, light progressive brakes, they are still limited by the grip that the skinny motorcycle tyres provide, but at least I can now feel that point.
I can explain how to do it if there are any other obsessives out there!!
_________________
KA

Better three than four.

[ka]

Twin leading shoes should have a moving piston at the leading end of each shoe, IE A single pistong either side of the set up, one for each lead.

As to the lining further back from the leading edge, I think it is to do with leverage and travel.

All brake shoes I have ever seen, Both SLS and TLS, have the lining toward the rear of the shoe away from the rotation.

The leading edge (the end of the shoe where the lining has a space) should be next to the wheel cylinder, even for SLS where both chamfered edged (leading edges) should surround the wheel cylinder. This gives braking when reversing due to reversed shoe and the servo effect.[/i]
_________________
KA

Better three than four.

[jessejazza]

I would be interested to hear how much better it is than SLS when you've been out on the road. I was thinking of SLS for the landrover simply because it is easier to adjust - TLS on a landy is a more lengthy exercise adjusting due to the weight of the vehicle and the poor design on the adjusters compared with say a Herald design.

[ka]

Instead of a left foot assisted braking, the brakes are light and progressive, with far more pedal movement.
_________________
KA

Better three than four.