Pete Lewis Posted September 10, 2023 Report Share Posted September 10, 2023 all you need is remove the wheel cylinder weld backplate wear and dress back no need to pop the hub or even remove the shoes Pete 1 Link to comment Share on other sites More sharing options...
Peter Truman Posted September 10, 2023 Report Share Posted September 10, 2023 Whilst reconditioning the back plates have a look at the handbrake lever return spring bracket it could be nearly worn through and a bit of weld stregthening may be appropriate. 1 Link to comment Share on other sites More sharing options...
johny Posted September 11, 2023 Report Share Posted September 11, 2023 (edited) 12 hours ago, Morgana said: Wouldn't this issue be solved if the handbrake lever pivots didn't project beyond the grooves in the cylinder housing? I'm sure the photographs I've seen have them sitting proud in the casting. Well it wouldnt help with wear as its the action of pulling on the handbrake that makes those grooves. The handbrake angle lever is pulled hard against the backplate and the pivots then rotate slightly to push the shoes out into contact with the drum. This action of pull and rotate plus a bit of road dirt is perfect for a grinding action☹️ If your handbrake is correctly adjusted and theres some slack in the cable I dont think slight grooves is any problem because the pivots can go back into the slave as it slides during braking. Saying that the last pattern slaves I fitted had poor castings and the pivot slots had to be opened up just to allow their installation.... Edited September 11, 2023 by johny Link to comment Share on other sites More sharing options...
Morgana Posted September 11, 2023 Report Share Posted September 11, 2023 Thanks all. In the light today, perhaps they're not as worn as I thought. The dips look quite shallow so I might get away with it for a while. The offside cylinder doesn't slide unless whacked - it seems much tighter than the nearside one which can be slid back and forth by hand. Should I put a smear of grease behind them? I wonder if both trailing shoes have been put on upside down, too. I haven't had the brakes apart yet, and having consulted the manual it looks as though the trailing shoe ought to have the rectangular hole downwards, but both sides have it upwards. Link to comment Share on other sites More sharing options...
Pete Lewis Posted September 11, 2023 Report Share Posted September 11, 2023 yes square hole at the bottom of the trailing shoe very common they are upside down need to do a fully readjust Pete Link to comment Share on other sites More sharing options...
johny Posted September 11, 2023 Report Share Posted September 11, 2023 I use coppaslip sparingly on all sliding surfaces in the drums... Link to comment Share on other sites More sharing options...
Unkel Kunkel Posted September 13, 2023 Report Share Posted September 13, 2023 (edited) Diag. Borrowed from elsewhere, this pic from W.manual with added comments in red Shows general arrangement - If the wheel cylinders don’t slide, hand brake efficiency is reduced. The back plate wear depression can impede the cylinder sliding. An answer is to mig weld -‘ fill up’ the wear depression -Copper lubricant is a popular choice. Edited September 13, 2023 by Unkel Kunkel Link to comment Share on other sites More sharing options...
johny Posted September 13, 2023 Report Share Posted September 13, 2023 In reality I wonder if theres ever much sliding of the slave under handbrake action. Its a lot to ask that as the pivot rotates and pushes the front shoe into contact with the drum it then starts to push the slave backwards while at the same time the pivot itself is being pulled hard against the backplate by the cable. I think its more likely our handbrakes only really use the leading shoe (explains why theyre weak) so the pivot/slave never moves and thats why we get the wear slots in a fixed spot.... Link to comment Share on other sites More sharing options...
Morgana Posted September 13, 2023 Report Share Posted September 13, 2023 Maybe a hard nylon strip... Great diagram, @Unkel Kunkel! Interesting that the Rimmer Bros. catalogue diagram shows the notch clearly on the trailing shoe at the top. Whoops! Link to comment Share on other sites More sharing options...
Unkel Kunkel Posted September 13, 2023 Report Share Posted September 13, 2023 (edited) 11 hours ago, johny said: In reality I wonder if theres ever much sliding of the slave under handbrake action. Its a lot to ask that as the pivot rotates and pushes the front shoe into contact with the drum it then starts to push the slave backwards while at the same time the pivot itself is being pulled hard against the backplate by the cable. I think its more likely our handbrakes only really use the leading shoe (explains why theyre weak) so the pivot/slave never moves and thats why we get the wear slots in a fixed spot.... Agree, there isn't ‘much’ sliding but what little there is seems to be needed - as it does seem to have a significant effect on handbrake efficiency. Over a few years, I have encountered similarly seized up cylinders ( ie unable to slide in the backplates) on a 100e Prefect and 105e Anglia and also a Spitfire.( They share the same sort of brake system) All had really hopeless handbrakes - which were transformed simply by freeing everything off- which entails dismantling the ‘horseshoe’ clips, lubricating ; dismantling and freeing of the adjuster and lubricating it and then adjusting. Edited September 13, 2023 by Unkel Kunkel Link to comment Share on other sites More sharing options...
johny Posted September 13, 2023 Report Share Posted September 13, 2023 Maybe on intial operation of the handbrake there is sliding and then its only when the tension really starts to bite as both shoes contact the drum that the pivot spigots grind the slots in the backplate? However as soon as the handbrake is released the spigots should pop back into their pockets in the slave leaving it free to slide wherever it wants.... Link to comment Share on other sites More sharing options...
Morgana Posted September 14, 2023 Report Share Posted September 14, 2023 I've found why the offside was not sliding - it had a retaining spring and two retaining plates behind it, while the sloppy nearside one only had the retaining spring. The adjuster was pretty seized too, so I've freed that off. I've put some rubber bands around the slave cylinders to check the movement without popping pistons. Are they duplex or simplex? In other words, should there be two pistons coming out or one? Both only have the forward piston moving on pressing the pedal. A quick blast with a 2.5mm rod and some filing brought the handbrake operating levers back to flat. I've decided not to weld up the backplates as it means dragging a welder round to the gravel, and finding a long enough extension lead. It would have to be arc as I haven't any MIG gas at the moment, and access for a rod isn't great. I'll attack it when I have the car in a garage, which ought to be in the next few weeks, depending on how the handbrake works after all this. Link to comment Share on other sites More sharing options...
johny Posted September 14, 2023 Report Share Posted September 14, 2023 Only one piston per slave cylinder so they have to slide to apply equal force to both shoes. Then there should be two retaining sprung clips on the other side of the backplate for each slave and they have to be installed the right way up to facilitate sliding. All in the manual.... Link to comment Share on other sites More sharing options...
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