Hydraulic handbrake

[Guy s]

Hi everyone, I've recently installed a new undercarriage on a Skyranger and in doing so I had to replace all of the pushlock hose fittings on the braking system as the originals started minor leaking when trying to bleed the brakes... Anyway I got that sorted.

 

But the seals in the master cylinder won't hold pressure so they need replacing, one's a square o-ring and one cup type O-ring which is a odd size and you can't buy anywhere in Oz... dealing with the Skyranger mob in England and them being a little slow returning emails is a little frustrating and I heard it just a case of them being very busy, but we're going thru the motions in working out what type I have to workout which seals I need... 

 

I just wonder if possible can you fit a handbrake system which on the Skyranger goes on the joystick that's used on motorbikes, 4wd buggy etc.. the only difference is the resoviour on a bike is flat ways and not upright like it would be on the joystick, but being a sealed unit I wouldn't think that would matter ?

So just wondering if anyone if anyone has used a braking system that was originally designed for bikes, buggies.

Just out of interest a new original handbrake is about $800

 

 

 

 

 

[facthunter]

Hydraulic Parking brakes are not secure unless they are a powered system and it's ON.. You are relying on O rings etc anyhow which do  fail. A mechanical back up which held them on at the wheels would be the go.  Nev

[skippydiesel]

Who mention "parking barkes"?

 

The question is about components ofa brake syetem.

 

 

[skippydiesel]

"Just out of interest a new original handbrake is about $800"

 

I have a brand new, unused, control stick mounted, brake master and possibly two preloved ones.

 

I would be willing to part with what I have - if interested contact me through the person to person service.

 

 

[facthunter]

It's a fairly basic aeroplane that only has a non differential Handbrake to stop you.  Nev

[onetrack]

There is a difference between a "handbrake", and a "hand-operated" brake. Most people immediately think of "parking brake", when "handbrake" is mentioned.

[facthunter]

Well you can't steer with it . when it's only got one master cylinder. The planes I've flown with such an arrangement are OK without it, ON GRASS.  Nev

[spenaroo]

Go for one with a remote reservoir.
common for the rear brake to be mounted sideways on motorcycles. with the reservoir linked via short hose.
right way up. they do these set-ups as well on the sport bikes as its easier to package with clip-on bars and fairings

[turboplanner]

18 hours ago, skippydiesel said:

Who mention "parking barkes"?

 

The question is about components ofa brake syetem.

 

 

The OP, "Hydraulic handbrake"

[spitfire]

Hello Guy

Ive got exactly the same issue with my Skyranger swift. As you probably already know, there is an overhaul kit available from Flylight , but there is some doubt about getting the right kit, apparently.

My Swift is 11 years old btw.

Its a pity we can’t just buy new o rings.

 I’m doubtful that Flylight manufacture the hydraulic unit. I’m guessing it’s from a moped or similar.

And yes they are slow on emails. I’m waiting on a reply…

would you like to send me a pm?

cheers

michael

 

 

[spitfire]

Hello Guy

Ive got exactly the same issue with my Skyranger swift. As you probably already know, there is an overhaul kit available from Flylight , but there is some doubt about getting the right kit, apparently.

My Swift is 11 years old btw.

Its a pity we can’t just buy new o rings.

 I’m doubtful that Flylight manufacture the hydraulic unit. I’m guessing it’s from a moped or similar.

And yes they are slow on emails. I’m waiting on a reply…

would you like to send me a pm?

cheers

michael

 

 

[Guy s]

Hi Michael (spitfire) and I'll send you a message with my number..

Flylight sent me the same photo and said the o-rings for that unit measures 12.6mm. I measure the bore and mine measures 13mm so 12.6mm wouldn't suit ofcause.

I've sent them some photos of the brake unit and it has aeroparts imprinted on the side which I post here and the bore size so hopefully they be able to work it out.

 

Mother option is to get a new piston machine and rebore the master cylinder to suit o-rings that are ready available here... I believe 14mm is a common size here. I know I can get the cup o-ring to suit a 9/16 bore also but I would have to change from hydraulic oil to a mineral oil plus swap the o-rings in the brake callipers to suit mineral oil which is not a drama as they are readily available here.

 

The easiest option would be to get the right o-rings off Flylight plus a spare set but it could be a long process.

 

[Guy s]

On 30/07/2023 at 7:40 PM, skippydiesel said:

"Just out of interest a new original handbrake is about $800"

 

I have a brand new, unused, control stick mounted, brake master and possibly two preloved ones.

 

I would be willing to part with what I have - if interested contact me through the person to person service.

 

 

Thanks Skppydiesel and I might just do that yet...

[onetrack]

Find an industrial hydraulics/seals supplier and they should be able to supply o-rings to fit virtually anything.

[Blueadventures]

2 hours ago, Guy s said:

Hi Michael (spitfire) and I'll send you a message with my number..

Flylight sent me the same photo and said the o-rings for that unit measures 12.6mm. I measure the bore and mine measures 13mm so 12.6mm wouldn't suit ofcause.

I've sent them some photos of the brake unit and it has aeroparts imprinted on the side which I post here and the bore size so hopefully they be able to work it out.

 

Mother option is to get a new piston machine and rebore the master cylinder to suit o-rings that are ready available here... I believe 14mm is a common size here. I know I can get the cup o-ring to suit a 9/16 bore also but I would have to change from hydraulic oil to a mineral oil plus swap the o-rings in the brake callipers to suit mineral oil which is not a drama as they are readily available here.

 

The easiest option would be to get the right o-rings off Flylight plus a spare set but it could be a long process.

 

Hi Guy that is different to to one I have in my 2012 model Nynja kit.  Can you sleve yours to the id if the later kits. Sounds like 12.6mm as that would allow using the available piston kit.  Best also to check actual bore size.  I’m away for next two weeks or more so unable to measure mine.  Maybe ask Greg R. Cheers

[skippydiesel]

Try this supplier for a wide range of brake  components http://www.kasparaero.cz/foto/download/en/29.pdf

 

Australian supplier of  brake seals etc : https://www.ibsbrakeparts.com.au/

Edited July 31, 2023 by skippydiesel

[facthunter]

The reservoir has to be above the master cylinder also. Another oil sometimes used is  SILICONE based. Mineral oils are not suitable in contact with rubber. The "Normal" brake fluids absorb water and damage paint and corrode a bit so I don't like them much.  Nev

[Blueadventures]

36 minutes ago, facthunter said:

The reservoir has to be above the master cylinder also. Another oil sometimes used is  SILICONE based. Mineral oils are not suitable in contact with rubber. The "Normal" brake fluids absorb water and damage paint and corrode a bit so I don't like them much.  Nev

For info these use DOT4 fluid

[facthunter]

Which is designed for max brake temp disc brakes towing and so forth. Need s regular flushing and bleeding,.   Most U/L and light  aircraft brakes  don't prioritise that aspect of their brake fluids.. Stick to what the BOOK says as you don't want to mix them but a lot of the planes I've encountered use MINERAL based oils.  Nev

[skippydiesel]

45 minutes ago, Blueadventures said:

For info these use DOT4 fluid

Automotive Dot 3, 4 & 5.1,  are all suitable

 

AND

 

The master cylinder does not require a reservoir - in fact fitting a reservoir would require the acquisition/fitting of a non return valve, assuming this is a piratical modification.

 

The choice of brake fluid is governed by the type of seals used in the system - not by the systems application. In some instances it may be possible (practical?) to change the seals so as to suit a different (cheaper/more widely available) fluid.

 

I would speculate, that silicone brake fluid may be the the least likely to attack, most if not all, brake seals but its costly.

 

 

[facthunter]

Mineral would be the cheapest.  The others are more  expensive but you waste a lot when Bleeding and often need special equipment to have the air out.  Spongy pedal/lever otherwise. The one way valves are in the ports of the master cylinder, closed off by the O rings/Cups. Sometimes there's a very fine "petal"washer closing off small holes in the Cup end of the piston.. While none of this is rocket science IF you're waiting to cross a runway where there's RPT active you wouldn't want to roll onto  the runway accidently at the wrong time either.  Nev

[Guy s]

9 hours ago, Blueadventures said:

Hi Guy that is different to to one I have in my 2012 model Nynja kit.  Can you sleve yours to the id if the later kits. Sounds like 12.6mm as that would allow using the available piston kit.  Best also to check actual bore size.  I’m away for next two weeks or more so unable to measure mine.  Maybe ask Greg R. Cheers

Hi Mike and the brake unit looks to be made of of some sort of composite so I'm not sure if there's enough thickness in the existing sleeve to be able to releeve it, but on saying that in the next few days I'm going to take it into a brake reconditioned specialist that I gotten to know and he'll be able to answer that with a yes or no.

 

Also just out of interest going either up or down in dia. effects the braking and the effort needed on the handbrake.  Both have there pluses and minus apparently and I haven't got my head around that one yet. But if the thickness is there in the bore to bore it out to 14mm or sleeve to the 12.6mm I'll have to make a choice.

[onetrack]

I've used silicone brake fluid many years ago, in an item of construction machinery. It was used to get around a major corrosion problem in the disc brake calipers. It worked just fine, and eliminated all the constant corrosion problems caused by using regular brake fluid. However, the silicone brake fluid was pricey, and it's an "oilier" product, with a higher viscosity than regular brake fluid.

I had a lot less brake problems when I used it, the downsides were - ensuring only silicone fluid was used for top up, and having to keep spare silicone fluid near to where the machine was working, or on board.

[turboplanner]

7 hours ago, onetrack said:

I've used silicone brake fluid many years ago, in an item of construction machinery. It was used to get around a major corrosion problem in the disc brake calipers. It worked just fine, and eliminated all the constant corrosion problems caused by using regular brake fluid. However, the silicone brake fluid was pricey, and it's an "oilier" product, with a higher viscosity than regular brake fluid.

I had a lot less brake problems when I used it, the downsides were - ensuring only silicone fluid was used for top up, and having to keep spare silicone fluid near to where the machine was working, or on board.

A good example for this is the household rubiish trailer.

[Guy s]

I got a email last night from Flylight saying they have worked out the o-rings I need and I've paid the invoice, so hopefully I'll have them in about 1-2 weeks plus a spare set. 

 

I guess since the new mob took over (Flylight) in 2017 I think they've made a few changes on the Skyrangers and then having to supply parts on the earlier French built planes and the changes they made over time must be a slight headache for them .

Anyway hopefully be back flying in a few weeks and thanks everyone for their input.

Cheers Guy.