TR4 handbrake button

[AndyR100]

Hi All,

quick question which I hope someone can confirm - the button on the end of the fly-off handbrake on my TR4 decided to live up to its name today - it flew off 

Before I do any unwitting damage - does it just need to wiggle back onto the pawl release rod from the top? Any particular technique to make sure it stays put (at least for a while!)

Thanks in advance for any help……. Andy 

[MichaelH]

Yes stick the button back on the wire - better with Aradite or similar

It works on compression - being a TR4 it will release (Fly off) on lifting the handbrake lever, so you can't really do it wrong

Michael H

[AndyR100]

18 hours ago, MichaelH said:

Yes stick the button back on the wire - better with Aradite or similar

It works on compression - being a TR4 it will release (Fly off) on lifting the handbrake lever, so you can't really do it wrong

Michael H

Hi Michael,

many thanks for your reply - I tried to do it today but unfortunately discovered that it was more than a button-malfunction.

The pawl release rod has actually broken close to the pawl - at least I know the real reason for the button popping off. I don’t think the rod itself has been available for some time, the guys at The TR Shop are going to have a search in their spares to see if they can help me out otherwise I’ll have to try and fabricate something that will do the job.

On the positive side, my left leg will probably enjoy the extra room  

…… Andy

[AndyR100]

Unfortunately, after a few phone calls I haven’t been able to get hold of a pawl-release rod for my handbrake, I will need to keep searching.

……. Andy 

[BlueTR3A-5EKT]

I think it’s a length of shaped 1/8” or 3 mm piano wire.   Welding rods is normally not strong enough in compression.

 

PS I do have a new hand brake lever somewhere if you want a pattern to copy 

PPS.  Silver steel in the right diameter could be shaped and tempered to do the job.

Edited May 11, 2022 by BlueTR3A-5EKT

[AndyR100]

22 minutes ago, BlueTR3A-5EKT said:

I think it’s a length of shaped 1/8” or 3 mm piano wire.   Welding rods is normally not strong enough in compression.

 

PS I do have a new hand brake lever somewhere if you want a pattern to copy 

PPS.  Silver steel in the right diameter could be shaped and tempered to do the job.

Hi Peter,

I was wondering whether some 2.5/3mm steel bar could be worked fit and do the job - I had’nt considered piano wire.  I do have an iron in the fire which Hamish kindly pointed me to and hope to know one way or the other tomorrow.

Thank you for your kind offer of one to take a pattern from - if I can’t get hold of one or fail with my fabrication-efforts  I may well take you up on the offer - it is greatly appreciated! 
 

cheers….. Andy 

[Lebro]

You should be able to buy piano wire at any good model shop. It's commonly used for Radio controled aircraft landing gear.

Bob

[John Morrison]

Andy,

just caught this thread are you sorted,

if no, I might be able to help, let me know this evening - TR'ing all day.

John.

[AndyR100]

14 hours ago, John Morrison said:

Andy,

just caught this thread are you sorted,

if no, I might be able to help, let me know this evening - TR'ing all day.

John.

Thanks John - I have dropped you a message 

cheers….. Andy

 

[MichaelH]

As the hand brake lever is pressing on your leg: why not move the hand brake to the tunnel an do what Tony Sheack had done  on his Rally cars (seen recently on a different thread ) and redirect the cable.

The TR4A handbrake structures should be a lot more available.

Make a virtue out of necessity?

Good luck

Michael H

[John Morrison]

Replied Andy,

John.

[AndyR100]

57 minutes ago, MichaelH said:

As the hand brake lever is pressing on your leg: why not move the hand brake to the tunnel an do what Tony Sheack had done  on his Rally cars (seen recently on a different thread ) and redirect the cable.

The TR4A handbrake structures should be a lot more available.

Make a virtue out of necessity?

Good luck

Michael H

Hi Michael,

to be honest it isn’t that much of a problem - but there is certainly more room in there without the handbrake. I think I’ll replace like with like - I have always appreciated the good leverage provided by the long lever and the chrome finish is rather stylish (in my eyes).

Fortunately, John has come up trumps on the rod, so I should be brake-legal again soon  

cheers…. Andy

[AndyR100]

29 minutes ago, John Morrison said:

Replied Andy,

John.

Thanks John - really appreciate your help  

cheers….. Andy

[AndyR100]

Just to round this one off……  I have managed to return to normal handbrake operation courtesy of @John Morrison who had a spare pawl release rod and posted it out to me super-fast, thank you John!

Peter @BlueTR3A-5EKT suggested piano wire could be used to fabricate a replacement - you were quite right Peter!  I have used some 3mm piano wire to make a spare just in case I have a repeat performance.

Thanks Bob @Lebro for suggesting a decent model shop as a source for the piano wire - our local shop disappeared years ago but the Addlestone Model Centre came up trumps! 

For anyone doing this job, it is a bit of a fiddle - I found that a piece of dowel to press the button/rod into the handle while getting the pawl/clevis pin and ratchet back in helped a lot.

I didn’t manage to find an easy way of getting the handbrake pivot-bolt lock nut on without moving the exhaust - if anyone has my tricks for the future I’m all-ears!

thanks gain to everyone who helped - it is greatly-appreciated  

cheers…… Andy