Handbrake on drum brakes - odd behaviour

[ArthurH 7]

The vehicle in question is my son's Brian James 'Minno' trailer but I'm not sure the question is actually vehicle specific.  The trailer has four-wheel braking - cable operated drums.

The trailer had rolled backward while the handbrake was on, both surprising us and damaging the tailgate of the 205 that was on it.  We jacked the trailer up and checked the effect of the hand brake on each wheel.  All four wheels behaved exactly the same.  At 10% of the handbrake travel the wheel could still spin freely.  At 30%  the wheels became very difficult to rotate forward by hand.  At 35% completely stopping forward rotation.  However, even at 35% the wheels could be easily rotated backward by hand!  All the way to 90% the wheels could be rotated backward by hand, only at 95% we couldn't turn them.

Has anyone seen this before?  Is it due to odd shoe wear or something?

TiA

 

 

[SRDT 177]

It's probably this;

 

There must be someting wrong with the shoes that are leading in reverse.

[welshpug 1,657]

Auto reverse mechanism I believe that will be, handbrake needs adjusting up more to hold it.

[ArthurH 7]

Apologies (again) the "Notify me of replies"  failed me again   I have spotted that I originally created my account with an email address that I had aliased after moving to a new email, but has just been 'ended' by the provider.  Should be OK going forward

 

 

Thanks Baptise, that does make a lot of sense.  I had heard of 'leading' and 'trailing' brake shoes, but not really understood the implication.  Can I assume that it is a 'function' of the brake design and not, in our case, an assembly error?

 

 

Mei, we did try adjusting the brakes to the point where they were rubbing even with the handbrake fully down, but it didn't seem to resolve the issue.  So we slackened it off a tad to ensure they didn't bind.

Edited November 27, 2023 by ArthurH