Trailer brakes

[Odyssey]

But of course this is describing the forces by vector so a 2D representation. There will also be forces in the Z plane due to the windage from air currents caused by the towing vehicle and also vibrational forces due to the damping response of the tyres/axles. All of which will not be constant but periodic based on velocity. 
 

The long and short of it, fit new brakes, sell boat, get that new one out the Solent on the wrecks and catch something else than doggies 😉 

[Andy135]

1 minute ago, Odyssey said:

catch something else than doggies 😉 

But.... why....?? 🐶🐟🤣

[Odyssey]

1 hour ago, Andy135 said:

But.... why....?? 🐶🐟🤣

Better eating on pollack, keeps the kids happy so you can go out more often 😉 

[suzook12]

9 hours ago, GPSguru said:

 

something mass'

Kinetic?

[Gordmac]

22 hours ago, GPSguru said:

@JonC, @Andy135 , @suzook12 , @Geoff

 

Here you go............

Decelerating mass is almost a sinusoidal function, which is why it is similar to wave mass calculation.

u(x, t) = 2a²·sech²(a(x + 4a²t))

u is the vertical displacement from equilibrium, t is time, x is horizontal distance and v is velocity,  sech(z) is the hyperbolic secant function and is equal to 2/(exp(z)+exp(−z)

 

Something using hyperbolic functions, not too common! Used to teach shear diffusion that included them, too hard for the students so we dropped it. Not that I can remember any of it now.

From what I can remember from when I towed a fair bit the hitch damper was just that, stopped the trailer from hammering into the towbar under braking by damping the movement.

[GPSguru]

 

5 minutes ago, Gordmac said:

shear diffusion

As in liquids............ water, Oil, Blood etc ?

[Gordmac]

As in vehicle structures.

[Andy135]

Well done @GPSguru. Looks like your suggestion of the brake coupling was correct. I removed the coupling assembly then lo and behold...

I'll take the coupling assembly home to free off on the bench but it may need a replacement damper.

[GPSguru]

7 hours ago, Andy135 said:

Well done @GPSguru. Looks like your suggestion of the brake coupling was correct. I removed the coupling assembly then lo and behold...

I'll take the coupling assembly home to free off on the bench but it may need a replacement damper.

Excellent. However, you need a wallet warning as dampers tend to be expensive (£60 ish).

once stripped snd cleaned the coupling may be ok. Use lithium grease (wheel bearing grease ) for reassembly.

Edited April 24, 2021 by GPSguru

[suzook12]

I did ask if everthing was backed off.... Yes you said!!!!

Good it's sorted now........

[Andy135]

21 minutes ago, suzook12 said:

I did ask if everthing was backed off.... Yes you said!!!!

Good it's sorted now........

Oops! 🤦‍♂️

[GPSguru]

10 minutes ago, Andy135 said:

Oops! 🤦‍♂️

 

Does the stub axle have the alko 'one shot' nut ? ............... if so then it must be renewed and requires to be done up to 290nm to preload the bearing.

290nm is a fair bit more than 3 grunts and a hernia, I use a 350nm torque wrench.

[Andy135]

2 hours ago, GPSguru said:

 

Does the stub axle have the alko 'one shot' nut ? ............... if so then it must be renewed and requires to be done up to 290nm to preload the bearing.

290nm is a fair bit more than 3 grunts and a hernia, I use a 350nm torque wrench.

Yes. Have two new ones waiting in the wings plus torque wrench plus length of scaffold tube for the required leverage.

[suzook12]

People don't seem to realise how important and versatile a tool a hammer is!!! From checking tightness of wheel nuts (wheel tappers- heard of them?) right through to forming shapes in metal work.

Despite being thought of as a mechanical weapon of mass destruction by the pro luddites, it can also be used as a precision engineering tool..... That is why there are so many shapes and sizes. Not every hammer is a 7lb club hammer!!

Don't blame others for your own crude use of such a versatile piece of equipment, at no point was it advised to bludgeon anything to death!! 👍

[suzook12]

9 hours ago, JonC said:

Perhaps a fully illustrated guide would help us understand, fixing everything from plotter screens to oil tanker anchors?

I could, but you'd need to read the words as well which makes me feel my time would be wasted

[Andy135]

Apache is now back on her own two wheels again. The brake coupling was too far siezed to be repaired, so I invested in a brand new one which I fitted today.

 

The drums went on and the nuts were done up (all 290nm of them)

 

And now she's ready for viewings...

[GPSguru]

(all290nm of them)
 

definitely more than the usual 3 grunts and a hernia 🤣

[Andy135]

1 minute ago, GPSguru said:

(all290nm of them)
 

definitely more than the usual 3 grunts and a hernia 🤣

You're not wrong! 🥵

Luckily I have a length of scaffold tube that is a lifesaver for situations such as these.

[Saintly Fish]

Good luck with finding a happy buyer. 

[Andy135]

1 minute ago, Saintly Fish said:

Good luck with finding a happy buyer. 

Thanks Neil. Part of me wants to keep her and trail to the south-west for fishing getaways but it feels a bit decadent to run a boat just for the odd weekend's fishing, so she needs to go before I change my mind...

[Saintly Fish]

1 hour ago, Andy135 said:

Thanks Neil. Part of me wants to keep her and trail to the south-west for fishing getaways but it feels a bit decadent to run a boat just for the odd weekend's fishing, so she needs to go before I change my mind...

Yeah it’s a nice idea, but an expensive one for the amount of use she’d get. A new owner would give her the fishing trips and dog fish she deserves! 

[suzook12]

4 hours ago, Andy135 said:

Thanks Neil. Part of me wants to keep her and trail to the south-west for fishing getaways but it feels a bit decadent to run a boat just for the odd weekend's fishing, so she needs to go before I change my mind...

I think you should offer it as a prize on this forum.......